qcodes.instrument_drivers.tektronix package

Submodules

qcodes.instrument_drivers.tektronix.AWG5014 module

qcodes.instrument_drivers.tektronix.AWG5014.parsestr(v: str) → str

class qcodes.instrument_drivers.tektronix.AWG5014.Tektronix_AWG5014(*args: Any, **kwargs: Any)

Bases: VisaInstrument

This is the QCoDeS driver for the Tektronix AWG5014 Arbitrary Waveform Generator.

The driver makes some assumptions on the settings of the instrument:

• The output channels are always in Amplitude/Offset mode

• The output markers are always in High/Low mode

Todo

• Implement support for cable transfer function compensation

• Implement more instrument functionality in the driver

• Remove double functionality

• Remove inconsistensies between the name of a parameter and the name of the same variable in the tektronix manual

In the future, we should consider the following:

• Removing test_send??

• That sequence element (SQEL) parameter functions exist but no corresponding parameters.

Initializes the AWG5014.

Parameters

• name – name of the instrument

• address – GPIB or ethernet address as used by VISA

• timeout – visa timeout, in secs. long default (180) to accommodate large waveforms

• num_channels – number of channels on the device

AWG_FILE_FORMAT_HEAD = {'CLOCK_SOURCE': 'h', 'COUPLING': 'h', 'DIVIDER_RATE': 'h', 'EVENT_INPUT_IMPEDANCE': 'h', 'EVENT_INPUT_POLARITY': 'h', 'EVENT_INPUT_THRESHOLD': 'd', 'EXTERNAL_REFERENCE_TYPE': 'h', 'HOLD_REPETITION_RATE': 'h', 'INTERLEAVE': 'h', 'INTERLEAVE_ADJ_AMPLITUDE': 'd', 'INTERLEAVE_ADJ_PHASE': 'd', 'INTERNAL_TRIGGER_RATE': 'd', 'JUMP_TIMING': 'h', 'REFERENCE_CLOCK_FREQUENCY_SELECTION': 'h', 'REFERENCE_MULTIPLIER_RATE': 'h', 'REFERENCE_SOURCE': 'h', 'REPETITION_RATE': 'd', 'RUN_MODE': 'h', 'RUN_STATE': 'h', 'SAMPLING_RATE': 'd', 'TRIGGER_INPUT_IMPEDANCE': 'h', 'TRIGGER_INPUT_POLARITY': 'h', 'TRIGGER_INPUT_SLOPE': 'h', 'TRIGGER_INPUT_THRESHOLD': 'd', 'TRIGGER_SOURCE': 'h', 'WAIT_VALUE': 'h', 'ZEROING': 'h'}

AWG_FILE_FORMAT_CHANNEL = {'ANALOG_AMPLITUDE_N': 'd', 'ANALOG_DIRECT_OUTPUT_N': 'h', 'ANALOG_FILTER_N': 'h', 'ANALOG_HIGH_N': 'd', 'ANALOG_LOW_N': 'd', 'ANALOG_METHOD_N': 'h', 'ANALOG_OFFSET_N': 'd', 'CHANNEL_SKEW_N': 'd', 'CHANNEL_STATE_N': 'h', 'DC_OUTPUT_LEVEL_N': 'd', 'DELAY_IN_POINTS_N': 'd', 'DELAY_IN_TIME_N': 'd', 'DIGITAL_AMPLITUDE_N': 'd', 'DIGITAL_HIGH_N': 'd', 'DIGITAL_LOW_N': 'd', 'DIGITAL_METHOD_N': 'h', 'DIGITAL_OFFSET_N': 'd', 'EXTERNAL_ADD_N': 'h', 'MARKER1_AMPLITUDE_N': 'd', 'MARKER1_HIGH_N': 'd', 'MARKER1_LOW_N': 'd', 'MARKER1_METHOD_N': 'h', 'MARKER1_OFFSET_N': 'd', 'MARKER1_SKEW_N': 'd', 'MARKER2_AMPLITUDE_N': 'd', 'MARKER2_HIGH_N': 'd', 'MARKER2_LOW_N': 'd', 'MARKER2_METHOD_N': 'h', 'MARKER2_OFFSET_N': 'd', 'MARKER2_SKEW_N': 'd', 'OUTPUT_WAVEFORM_NAME_N': 's', 'PHASE_DELAY_INPUT_METHOD_N': 'h', 'PHASE_N': 'd'}

newlinestripper(string: str) → str

get_state() → Literal['Idle', 'Waiting for trigger', 'Running']

This query returns the run state of the arbitrary waveform generator or the sequencer.

Returns

Either ‘Idle’, ‘Waiting for trigger’, or ‘Running’.

Raises

ValueError – if none of the three states above apply.

start() → str

Convenience function, identical to self.run()

run() → str

This command initiates the output of a waveform or a sequence. This is equivalent to pressing Run/Stop button on the front panel. The instrument can be put in the run state only when output waveforms are assigned to channels.

Returns

The output of self.get_state()

stop() → None

This command stops the output of a waveform or a sequence.

force_trigger() → None

This command generates a trigger event. This is equivalent to pressing the Force Trigger button on front panel.

get_folder_contents(print_contents: bool = True) → str

This query returns the current contents and state of the mass storage media (on the AWG Windows machine).

Parameters

print_contents – If True, the folder name and the query output are printed. Default: True.

Returns

A comma-seperated string of the folder contents.

Return type

str

get_current_folder_name() → str

This query returns the current directory of the file system on the arbitrary waveform generator. The current directory for the programmatic interface is different from the currently selected directory in the Windows Explorer on the instrument.

Returns

A string with the full path of the current folder.

set_current_folder_name(file_path: str) → int

Set the current directory of the file system on the arbitrary waveform generator. The current directory for the programmatic interface is different from the currently selected directory in the Windows Explorer on the instrument.

Parameters

file_path – The full path.

Returns

The number of bytes written to instrument

change_folder(folder: str) → int

Duplicate of self.set_current_folder_name

goto_root() → None

Set the current directory of the file system on the arbitrary waveform generator to C: (the ‘root’ location in Windows).

create_and_goto_dir(folder: str) → str

Set the current directory of the file system on the arbitrary waveform generator. Creates the directory if if doesn’t exist. Queries the resulting folder for its contents.

Parameters

folder – The path of the directory to set as current. Note: this function expects only root level directories.

Returns

A comma-seperated string of the folder contents.

all_channels_on() → None

Set the state of all channels to be ON. Note: only channels with defined waveforms can be ON.

all_channels_off() → None

Set the state of all channels to be OFF.

force_trigger_event() → None

This command generates a trigger event. Equivalent to self.force_trigger.

force_event() → None

This command generates a forced event. This is used to generate the event when the sequence is waiting for an event jump. This is equivalent to pressing the Force Event button on the front panel of the instrument.

set_sqel_event_target_index(element_no: int, index: int) → None

This command sets the target index for the sequencer’s event jump operation. Note that this will take effect only when the event jump target type is set to INDEX.

Parameters

• element_no – The sequence element number

• index – The index to set the target to

set_sqel_goto_target_index(element_no: int, goto_to_index_no: int) → None

This command sets the target index for the GOTO command of the sequencer. After generating the waveform specified in a sequence element, the sequencer jumps to the element specified as GOTO target. This is an unconditional jump. If GOTO target is not specified, the sequencer simply moves on to the next element. If the Loop Count is Infinite, the GOTO target which is specified in the element is not used. For this command to work, the goto state of the squencer must be ON and the sequence element must exist. Note that the first element of a sequence is taken to be 1 not 0.

Parameters

• element_no – The sequence element number

• goto_to_index_no – The target index number

set_sqel_goto_state(element_no: int, goto_state: int) → None

This command sets the GOTO state of the sequencer for the specified sequence element.

Parameters

• element_no – The sequence element number

• goto_state – The GOTO state of the sequencer. Must be either 0 (OFF) or 1 (ON).

set_sqel_loopcnt_to_inf(element_no: int, state: int = 1) → None

This command sets the infinite looping state for a sequence element. When an infinite loop is set on an element, the sequencer continuously executes that element. To break the infinite loop, issue self.stop()

Parameters

• element_no (int) – The sequence element number

• state (int) – The infinite loop state. Must be either 0 (OFF) or 1 (ON).

get_sqel_loopcnt(element_no: int = 1) → str

This query returns the loop count (number of repetitions) of a sequence element. Loop count setting for an element is ignored if the infinite looping state is set to ON.

Parameters

element_no – The sequence element number. Default: 1.

set_sqel_loopcnt(loopcount: int, element_no: int = 1) → None

This command sets the loop count. Loop count setting for an element is ignored if the infinite looping state is set to ON.

Parameters

• loopcount – The number of times the sequence is being output. The maximal possible number is 65536, beyond that: infinity.

• element_no – The sequence element number. Default: 1.

set_sqel_waveform(waveform_name: str, channel: int, element_no: int = 1) → None

This command sets the waveform for a sequence element on the specified channel.

Parameters

• waveform_name – Name of the waveform. Must be in the waveform list (either User Defined or Predefined).

• channel – The output channel (1-4)

• element_no – The sequence element number. Default: 1.

get_sqel_waveform(channel: int, element_no: int = 1) → str

This query returns the waveform for a sequence element on the specified channel.

Parameters

• channel – The output channel (1-4)

• element_no – The sequence element number. Default: 1.

Returns

The name of the waveform.

set_sqel_trigger_wait(element_no: int, state: int = 1) → str

This command sets the wait trigger state for an element. Send a trigger signal in one of the following ways:

• By using an external trigger signal.

• By pressing the “Force Trigger” button on the front panel

• By using self.force_trigger or self.force_trigger_event

Parameters

• element_no – The sequence element number.

• state – The wait trigger state. Must be either 0 (OFF) or 1 (ON). Default: 1.

Returns

The current state (after setting it).

get_sqel_trigger_wait(element_no: int) → str

This query returns the wait trigger state for an element. Send a trigger signal in one of the following ways:

• By using an external trigger signal.

• By pressing the “Force Trigger” button on the front panel

• By using self.force_trigger or self.force_trigger_event

Parameters

element_no – The sequence element number.

Returns

‘1’.

Return type

The current state. Example

set_sqel_event_jump_target_index(element_no: int, jtar_index_no: int) → None

Duplicate of set_sqel_event_target_index

set_sqel_event_jump_type(element_no: int, jtar_state: str) → None

This command sets the event jump target type for the jump for the specified sequence element. Generate an event in one of the following ways:

• By connecting an external cable to instrument rear panel for external event.

• By pressing the Force Event button on the front panel.

• By using self.force_event

Parameters

• element_no – The sequence element number

• jtar_state – The jump target type. Must be either ‘INDEX’, ‘NEXT’, or ‘OFF’.

get_sq_mode() → str

This query returns the type of the arbitrary waveform generator’s sequencer. The sequence is executed by the hardware sequencer whenever possible.

Returns

Either ‘HARD’ or ‘SOFT’ indicating that the instrument is in either hardware or software sequencer mode.

Return type

str

generate_sequence_cfg() → Dict[str, float]

This function is used to generate a config file, that is used when generating sequence files, from existing settings in the awg. Querying the AWG for these settings takes ~0.7 seconds

generate_channel_cfg() → Dict[str, Optional[float]]

Function to query if the current channel settings that have been changed from their default value and put them in a dictionary that can easily be written into an awg file, so as to prevent said awg file from falling back to default values. (See make_awg_file() and AWG_FILE_FORMAT_CHANNEL()) NOTE: This only works for settings changed via the corresponding QCoDeS parameter.

Returns

A dict with the current setting for each entry in AWG_FILE_FORMAT_HEAD iff this entry applies to the AWG5014 AND has been changed from its default value.

static parse_marker_channel_name(name: str) → _MarkerDescriptor

returns from the channel index and marker index from a marker descriptor string e.g. ‘1M1’->(1,1)

make_send_and_load_awg_file_from_forged_sequence(seq: Dict[Any, Any], filename: str = 'customawgfile.awg', preservechannelsettings: bool = True) → None

Makes an awg file form a forged sequence as produced by broadbean.sequence.Sequence.forge. The forged sequence is a dictionary (see fs_schmea) that does not need to be created by broadbean.

Parameters

• seq – the sequence dictionary

• filename – filename of the uploaded awg file. See make_send_and_load_awg_file()

• preservechannelsettings – see make_send_and_load_awg_file()

send_awg_file(filename: str, awg_file: bytes, verbose: bool = False) → None

Writes an .awg-file onto the disk of the AWG. Overwrites existing files.

Parameters

• filename – The name that the file will get on the AWG.

• awg_file – A byte sequence containing the awg_file. Usually the output of self.make_awg_file.

• verbose – A boolean to allow/suppress printing of messages about the status of the filw writing. Default: False.

load_awg_file(filename: str) → None

Loads an .awg-file from the disc of the AWG into the AWG memory. This may overwrite all instrument settings, the waveform list, and the sequence in the sequencer.

Parameters

filename – The filename of the .awg-file to load.

make_awg_file(waveforms: Union[Sequence[Sequence[ndarray]], Sequence[ndarray]], m1s: Union[Sequence[Sequence[ndarray]], Sequence[ndarray]], m2s: Union[Sequence[Sequence[ndarray]], Sequence[ndarray]], nreps: Sequence[int], trig_waits: Sequence[int], goto_states: Sequence[int], jump_tos: Sequence[int], channels: Optional[Sequence[int]] = None, preservechannelsettings: bool = True) → bytes

Parameters

• waveforms – A list of the waveforms to be packed. The list should be filled like so: [[wfm1ch1, wfm2ch1, …], [wfm1ch2, wfm2ch2], …] Each waveform should be a numpy array with values in the range -1 to 1 (inclusive). If you do not wish to send waveforms to channels 1 and 2, use the channels parameter.

• m1s – A list of marker 1’s. The list should be filled like so: [[elem1m1ch1, elem2m1ch1, …], [elem1m1ch2, elem2m1ch2], …] Each marker should be a numpy array containing only 0’s and 1’s

• m2s – A list of marker 2’s. The list should be filled like so: [[elem1m2ch1, elem2m2ch1, …], [elem1m2ch2, elem2m2ch2], …] Each marker should be a numpy array containing only 0’s and 1’s

• nreps – List of integers specifying the no. of repetitions per sequence element. Allowed values: 0 to 65536. O corresponds to Infinite repetitions.

• trig_waits – List of len(segments) of integers specifying the trigger wait state of each sequence element. Allowed values: 0 (OFF) or 1 (ON).

• goto_states – List of len(segments) of integers specifying the goto state of each sequence element. Allowed values: 0 to 65536 (0 means next)

• jump_tos – List of len(segments) of integers specifying the logic jump state for each sequence element. Allowed values: 0 (OFF) or 1 (ON).

• channels (list) – List of channels to send the waveforms to. Example: [1, 3, 2]

• preservechannelsettings (bool) – If True, the current channel settings are found from the parameter history and added to the .awg file. Else, channel settings are not written in the file and will be reset to factory default when the file is loaded. Default: True.

make_send_and_load_awg_file(waveforms: Sequence[Sequence[ndarray]], m1s: Sequence[Sequence[ndarray]], m2s: Sequence[Sequence[ndarray]], nreps: Sequence[int], trig_waits: Sequence[int], goto_states: Sequence[int], jump_tos: Sequence[int], channels: Optional[Sequence[int]] = None, filename: str = 'customawgfile.awg', preservechannelsettings: bool = True) → None

Makes an .awg-file, sends it to the AWG and loads it. The .awg-file is uploaded to C:\Users\OEM\Documents. The waveforms appear in the user defined waveform list with names wfm001ch1, wfm002ch1, …

Parameters

• waveforms – A list of the waveforms to upload. The list should be filled like so: [[wfm1ch1, wfm2ch1, …], [wfm1ch2, wfm2ch2], …] Each waveform should be a numpy array with values in the range -1 to 1 (inclusive). If you do not wish to send waveforms to channels 1 and 2, use the channels parameter.

• m1s – A list of marker 1’s. The list should be filled like so: [[elem1m1ch1, elem2m1ch1, …], [elem1m1ch2, elem2m1ch2], …] Each marker should be a numpy array containing only 0’s and 1’s

• m2s – A list of marker 2’s. The list should be filled like so: [[elem1m2ch1, elem2m2ch1, …], [elem1m2ch2, elem2m2ch2], …] Each marker should be a numpy array containing only 0’s and 1’s

• nreps – List of integers specifying the no. of repetions per sequence element. Allowed values: 0 to 65536. 0 corresponds to Infinite repetions.

• trig_waits – List of len(segments) of integers specifying the trigger wait state of each sequence element. Allowed values: 0 (OFF) or 1 (ON).

• goto_states – List of len(segments) of integers specifying the goto state of each sequence element. Allowed values: 0 to 65536 (0 means next)

• jump_tos – List of len(segments) of integers specifying the logic jump state for each sequence element. Allowed values: 0 (OFF) or 1 (ON).

• channels – List of channels to send the waveforms to. Example: [1, 3, 2]

• filename – The name of the .awg-file. Should end with the .awg extension. Default: ‘customawgfile.awg’

• preservechannelsettings – If True, the current channel settings are found from the parameter history and added to the .awg file. Else, channel settings are reset to the factory default values. Default: True.

make_and_save_awg_file(waveforms: Sequence[Sequence[ndarray]], m1s: Sequence[Sequence[ndarray]], m2s: Sequence[Sequence[ndarray]], nreps: Sequence[int], trig_waits: Sequence[int], goto_states: Sequence[int], jump_tos: Sequence[int], channels: Optional[Sequence[int]] = None, filename: str = 'customawgfile.awg', preservechannelsettings: bool = True) → None

Makes an .awg-file and saves it locally.

Parameters

• waveforms – A list of the waveforms to upload. The list should be filled like so: [[wfm1ch1, wfm2ch1, …], [wfm1ch2, wfm2ch2], …] Each waveform should be a numpy array with values in the range -1 to 1 (inclusive). If you do not wish to send waveforms to channels 1 and 2, use the channels parameter.

• m1s – A list of marker 1’s. The list should be filled like so: [[elem1m1ch1, elem2m1ch1, …], [elem1m1ch2, elem2m1ch2], …] Each marker should be a numpy array containing only 0’s and 1’s

• m2s – A list of marker 2’s. The list should be filled like so: [[elem1m2ch1, elem2m2ch1, …], [elem1m2ch2, elem2m2ch2], …] Each marker should be a numpy array containing only 0’s and 1’s

• nreps – List of integers specifying the no. of repetions per sequence element. Allowed values: 0 to 65536. O corresponds to Infinite repetions.

• trig_waits – List of len(segments) of integers specifying the trigger wait state of each sequence element. Allowed values: 0 (OFF) or 1 (ON).

• goto_states – List of len(segments) of integers specifying the goto state of each sequence element. Allowed values: 0 to 65536 (0 means next)

• jump_tos – List of len(segments) of integers specifying the logic jump state for each sequence element. Allowed values: 0 (OFF) or 1 (ON).

• channels – List of channels to send the waveforms to. Example: [1, 3, 2]

• preservechannelsettings – If True, the current channel settings are found from the parameter history and added to the .awg file. Else, channel settings are not written in the file and will be reset to factory default when the file is loaded. Default: True.

• filename – The full path of the .awg-file. Should end with the .awg extension. Default: ‘customawgfile.awg’

get_error() → str

This function retrieves and returns data from the error and event queues.

Returns

String containing the error/event number, the error/event description.

delete_all_waveforms_from_list() → None

Delete all user-defined waveforms in the list in a single action. Note that there is no “UNDO” action once the waveforms are deleted. Use caution before issuing this command.

If the deleted waveform(s) is (are) currently loaded into waveform memory, it (they) is (are) unloaded. If the RUN state of the instrument is ON, the state is turned OFF. If the channel is on, it will be switched off.

get_filenames() → str

Duplicate of self.get_folder_contents

send_DC_pulse(DC_channel_number: int, set_level: float, length: float) → None

Sets the DC level on the specified channel, waits a while and then resets it to what it was before.

Note: Make sure that the output DC state is ON.

Parameters

• DC_channel_number (int) – The channel number (1-4).

• set_level (float) – The voltage level to set to (V).

• length (float) – The time to wait before resetting (s).

is_awg_ready() → bool

Assert if the AWG is ready.

Returns

True, irrespective of anything.

send_waveform_to_list(w: ndarray, m1: ndarray, m2: ndarray, wfmname: str) → None

Send a single complete waveform directly to the “User defined” waveform list (prepend it). The data type of the input arrays is unimportant, but the marker arrays must contain only 1’s and 0’s.

Parameters

• w – The waveform

• m1 – Marker1

• m2 – Marker2

• wfmname – waveform name

Raises

• Exception – if the lengths of w, m1, and m2 don’t match

• TypeError – if the waveform contains values outside (-1, 1)

• TypeError – if the markers contain values that are not 0 or 1

clear_message_queue(verbose: bool = False) → None

Function to clear up (flush) the VISA message queue of the AWG instrument. Reads all messages in the the queue.

Parameters

verbose – If True, the read messages are printed. Default: False.

__del__() → None

Close the instrument and remove its instance record.

__getitem__(key: str) → Union[Callable[[...], Any], Parameter]

Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None

Prevent pickling instruments, and give a nice error message.

__repr__() → str

Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only. If your case is more complicated, you’re probably better off simply making a new method in your Instrument subclass definition.

Parameters

• name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.

• **kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[Type[ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

• name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.

• parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.

• **kwargs – Constructor arguments for parameter_class.

Raises

• KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.

• ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: Union[InstrumentModule, ChannelTuple]) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

• name – How the submodule will be stored within instrument.submodules and also how it can be addressed.

• submodule – The submodule to be stored.

Raises

• KeyError – If this instrument already contains a submodule with this name.

• TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: List[qcodes.instrument.instrument_base.InstrumentBase]

Returns a list of instruments, starting from the current instrument and following to the parent instrument and the parents parent instrument until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters

cmd – The string to send to the instrument.

Returns

response

Raises

Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters

cmd – The command to send to the instrument.

Returns

The instrument’s response.

Return type

str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

• func_name – The name of a function of this instrument.

• *args – any arguments to the function.

Returns

The return value of the function.

check_error(ret_code: int) → None

Default error checking, raises an error if return code !=0. Does not differentiate between warnings or specific error messages. Override this function in your driver if you want to add specific error messages.

Parameters

ret_code – A Visa error code. See eg: https://github.com/hgrecco/pyvisa/blob/master/pyvisa/errors.py

Raises

visa.VisaIOError – if ret_code indicates a communication problem.

close() → None

Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

• idn_param – Name of parameter that returns ID dict. Default IDN.

• begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']

A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []

A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None

Clear the buffers of the device

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

• name – Name of the instrument.

• instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[Type[T]] = None) → T

Find an existing instrument by name.

Parameters

• name – Name of the instrument.

• instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

• KeyError – If no instrument of that name was found, or if its reference is invalid (dead).

• TypeError – If a specific class was requested but a different type was found.

property full_name: str

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters

param_name – The name of a parameter of this instrument.

Returns

The current value of the parameter.

get_idn() → Dict[str, Optional[str]]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns

A dict containing vendor, model, serial, and firmware.

classmethod instances() → List[Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns

A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters

instr_instance – Instance of an Instrument class or its subclass.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters

metadata – Metadata to load.

property name: str

Name of the instrument This is equivalent to full_name for backwards compatibility.

property name_parts: List[str]

omit_delegate_attrs: List[str] = []

A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: Optional[qcodes.instrument.instrument_base.InstrumentBase]

Returns the parent instrument. By default this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

• update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.

• max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters

instance – Instance to record.

Raises

KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters

instance – The instance to remove

property root_instrument: qcodes.instrument.instrument_base.InstrumentBase

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

• param_name – The name of a parameter of this instrument.

• value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters

address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: Optional[str]) → None

Change the read terminator to use.

Parameters

terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

shared_kwargs = ()

property short_name: str

Short name of the instrument

snapshot(update: Optional[bool] = False) → Dict[Any, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters

update – Passed to snapshot_base.

Returns

Base snapshot.

snapshot_base(update: Optional[bool] = True, params_to_skip_update: Optional[Sequence[str]] = None) → Dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

• update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.

• params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

dict

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters

verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters

cmd – The string to send to the instrument.

Raises

Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters

cmd – The command to send to the instrument.

parameters: Dict[str, ParameterBase] = {}

All the parameters supported by this instrument. Usually populated via add_parameter().

functions: Dict[str, Function] = {}

All the functions supported by this instrument. Usually populated via add_function().

submodules: Dict[str, Union['InstrumentModule', 'ChannelTuple']] = {}

All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: Dict[str, 'InstrumentModule'] = {}

All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.tektronix.AWG5208 module

class qcodes.instrument_drivers.tektronix.AWG5208.AWG5208(*args: Any, **kwargs: Any)

Bases: AWG70000A

The QCoDeS driver for Tektronix AWG5208

Parameters

• name – The name used internally by QCoDeS in the DataSet

• address – The VISA resource name of the instrument

• timeout – The VISA timeout time (in seconds).

__del__() → None

Close the instrument and remove its instance record.

__getitem__(key: str) → Union[Callable[[...], Any], Parameter]

Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None

Prevent pickling instruments, and give a nice error message.

__repr__() → str

Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only. If your case is more complicated, you’re probably better off simply making a new method in your Instrument subclass definition.

Parameters

• name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.

• **kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[Type[ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

• name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.

• parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.

• **kwargs – Constructor arguments for parameter_class.

Raises

• KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.

• ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: Union[InstrumentModule, ChannelTuple]) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

• name – How the submodule will be stored within instrument.submodules and also how it can be addressed.

• submodule – The submodule to be stored.

Raises

• KeyError – If this instrument already contains a submodule with this name.

• TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: List[qcodes.instrument.instrument_base.InstrumentBase]

Returns a list of instruments, starting from the current instrument and following to the parent instrument and the parents parent instrument until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters

cmd – The string to send to the instrument.

Returns

response

Raises

Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters

cmd – The command to send to the instrument.

Returns

The instrument’s response.

Return type

str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

• func_name – The name of a function of this instrument.

• *args – any arguments to the function.

Returns

The return value of the function.

check_error(ret_code: int) → None

Default error checking, raises an error if return code !=0. Does not differentiate between warnings or specific error messages. Override this function in your driver if you want to add specific error messages.

Parameters

ret_code – A Visa error code. See eg: https://github.com/hgrecco/pyvisa/blob/master/pyvisa/errors.py

Raises

visa.VisaIOError – if ret_code indicates a communication problem.

clearSequenceList() → None

Clear the sequence list

clearWaveformList() → None

Clear the waveform list

close() → None

Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

• idn_param – Name of parameter that returns ID dict. Default IDN.

• begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']

A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []

A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

delete_sequence_from_list(seqname: str) → None

Delete the specified sequence from the sequence list

Parameters

seqname – The name of the sequence (as it appears in the sequence list, not the file name) to delete

device_clear() → None

Clear the buffers of the device

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

• name – Name of the instrument.

• instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[Type[T]] = None) → T

Find an existing instrument by name.

Parameters

• name – Name of the instrument.

• instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

• KeyError – If no instrument of that name was found, or if its reference is invalid (dead).

• TypeError – If a specific class was requested but a different type was found.

force_triggerA() → None

Force a trigger A event

force_triggerB() → None

Force a trigger B event

property full_name: str

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters

param_name – The name of a parameter of this instrument.

Returns

The current value of the parameter.

get_idn() → Dict[str, Optional[str]]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns

A dict containing vendor, model, serial, and firmware.

classmethod instances() → List[Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns

A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters

instr_instance – Instance of an Instrument class or its subclass.

loadSEQXFile(filename: str, path: Optional[str] = None) → None

Load a seqx file from instrument disk memory. All sequences in the file are loaded into the sequence list.

Parameters

• filename – The name of the sequence file INCLUDING the extension

• path – Path to load from. If omitted, the default path (self.seqxFileFolder) is used.

loadWFMXFile(filename: str, path: Optional[str] = None) → None

Loads a wfmx from memory into the waveform list Only loading from the C: drive is supported

Parameters

• filename – Name of the file (with extension)

• path – Path to load from. If omitted, the default path (self.wfmxFileFolder) is used.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters

metadata – Metadata to load.

static makeSEQXFile(trig_waits: Sequence[int], nreps: Sequence[int], event_jumps: Sequence[int], event_jump_to: Sequence[int], go_to: Sequence[int], wfms: Sequence[Sequence[ndarray]], amplitudes: Sequence[float], seqname: str, flags: Optional[Sequence[Sequence[Sequence[int]]]] = None) → bytes

Make a full .seqx file (bundle) A .seqx file can presumably hold several sequences, but for now we support only packing a single sequence

For a single sequence, a .seqx file is a bundle of two files and two folders:

/Sequences

sequence.sml

/Waveforms

wfm1.wfmx wfm2.wfmx …

setup.xml userNotes.txt

Parameters

• trig_waits – Wait for a trigger? If yes, you must specify the trigger input. 0 for off, 1 for ‘TrigA’, 2 for ‘TrigB’, 3 for ‘Internal’.

• nreps – No. of repetitions. 0 corresponds to infinite.

• event_jumps – Jump when event triggered? If yes, you must specify the trigger input. 0 for off, 1 for ‘TrigA’, 2 for ‘TrigB’, 3 for ‘Internal’.

• event_jump_to – Jump target in case of event. 1-indexed, 0 means next. Must be specified for all elements.

• go_to – Which element to play next. 1-indexed, 0 means next.

• wfms – numpy arrays describing each waveform plus two markers, packed like np.array([wfm, m1, m2]). These numpy arrays are then again packed in lists according to: [[wfmch1pos1, wfmch1pos2, …], [wfmch2pos1, …], …]

• amplitudes – The peak-to-peak amplitude in V of the channels, i.e. a list [ch1_amp, ch2_amp].

• seqname – The name of the sequence. This name will appear in the sequence list. Note that all spaces are converted to ‘_’

• flags – Flags for the auxiliary outputs. 0 for ‘No change’, 1 for ‘High’, 2 for ‘Low’, 3 for ‘Toggle’, or 4 for ‘Pulse’. 4 flags [A, B, C, D] for every channel in every element, packed like: [[ch1pos1, ch1pos2, …], [ch2pos1, …], …] If omitted, no flags will be set.

Returns

The binary .seqx file, ready to be sent to the instrument.

static makeWFMXFile(data: ndarray, amplitude: float) → bytes

Compose a WFMX file

Parameters

• data – A numpy array holding the data. Markers can be included.

• amplitude – The peak-to-peak amplitude (V) assumed to be set on the channel that will play this waveform. This information is needed as the waveform must be rescaled to (-1, 1) where -1 will correspond to the channel’s min. voltage and 1 to the channel’s max. voltage.

Returns

The binary .wfmx file, ready to be sent to the instrument.

static make_SEQX_from_forged_sequence(seq: Dict[int, Dict[Any, Any]], amplitudes: List[float], seqname: str, channel_mapping: Optional[Dict[Union[str, int], int]] = None) → bytes

Make a .seqx from a forged broadbean sequence. Supports subsequences.

Parameters

• seq – The output of broadbean’s Sequence.forge()

• amplitudes – A list of the AWG channels’ voltage amplitudes. The first entry is ch1 etc.

• channel_mapping – A mapping from what the channel is called in the broadbean sequence to the integer describing the physical channel it should be assigned to.

• seqname – The name that the sequence will have in the AWG’s sequence list. Used for loading the sequence.

Returns

The binary .seqx file contents. Can be sent directly to the

instrument or saved on disk.

property name: str

Name of the instrument This is equivalent to full_name for backwards compatibility.

property name_parts: List[str]

omit_delegate_attrs: List[str] = []

A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: Optional[qcodes.instrument.instrument_base.InstrumentBase]

Returns the parent instrument. By default this is None. Any SubInstrument should subclass this to return the parent instrument.

play(wait_for_running: bool = True, timeout: float = 10) → None

Run the AWG/Func. Gen. This command is equivalent to pressing the play button on the front panel.

Parameters

• wait_for_running – If True, this command is blocking while the instrument is getting ready to play

• timeout – The maximal time to wait for the instrument to play. Raises an exception is this time is reached.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

• update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.

• max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters

instance – Instance to record.

Raises

KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters

instance – The instance to remove

property root_instrument: qcodes.instrument.instrument_base.InstrumentBase

sendSEQXFile(seqx: bytes, filename: str, path: Optional[str] = None) → None

Send a binary seqx file to the AWG’s memory

Parameters

• seqx – The binary seqx file, preferably the output of makeSEQXFile.

• filename – The name of the file on the AWG disk, including the extension.

• path – The path to the directory where the file should be saved. If omitted, seqxFileFolder will be used.

sendWFMXFile(wfmx: bytes, filename: str, path: Optional[str] = None) → None

Send a binary wfmx file to the AWG’s memory

Parameters

• wfmx – The binary wfmx file, preferably the output of makeWFMXFile.

• filename – The name of the file on the AWG disk, including the extension.

• path – The path to the directory where the file should be saved. If omitted, seqxFileFolder will be used.

property sequenceList: List[str]

Return the sequence list as a list of strings

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

• param_name – The name of a parameter of this instrument.

• value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters

address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: Optional[str]) → None

Change the read terminator to use.

Parameters

terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

shared_kwargs = ()

property short_name: str

Short name of the instrument

snapshot(update: Optional[bool] = False) → Dict[Any, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters

update – Passed to snapshot_base.

Returns

Base snapshot.

snapshot_base(update: Optional[bool] = True, params_to_skip_update: Optional[Sequence[str]] = None) → Dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

• update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.

• params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

dict

stop() → None

Stop the output of the instrument. This command is equivalent to pressing the stop button on the front panel.

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters

verbose – If True, then information about the parameters that are being check is printed.

wait_for_operation_to_complete() → None

Waits for the latest issued overlapping command to finish

property waveformList: List[str]

Return the waveform list as a list of strings

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters

cmd – The string to send to the instrument.

Raises

Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters

cmd – The command to send to the instrument.

parameters: Dict[str, ParameterBase] = {}

All the parameters supported by this instrument. Usually populated via add_parameter().

functions: Dict[str, Function] = {}

All the functions supported by this instrument. Usually populated via add_function().

submodules: Dict[str, Union['InstrumentModule', 'ChannelTuple']] = {}

All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: Dict[str, 'InstrumentModule'] = {}

All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.tektronix.AWG70000A module

class qcodes.instrument_drivers.tektronix.AWG70000A.SRValidator(awg: AWG70000A)

Bases: Validator[float]

Validator to validate the AWG clock sample rate

Parameters

awg – The parent instrument instance. We need this since sample rate validation depends on many clock settings

validate(value: float, context: str = '') → None

is_numeric = False

property valid_values: Tuple[qcodes.validators.validators.T, ...]

class qcodes.instrument_drivers.tektronix.AWG70000A.AWGChannel(parent: Instrument, name: str, channel: int)

Bases: InstrumentChannel

Class to hold a channel of the AWG.

Parameters

• parent – The Instrument instance to which the channel is to be attached.

• name – The name used in the DataSet

• channel – The channel number, either 1 or 2.

setWaveform(name: str) → None

Select a waveform from the waveform list to output on this channel

Parameters

name – The name of the waveform

setSequenceTrack(seqname: str, tracknr: int) → None

Assign a track from a sequence to this channel.

Parameters

• seqname – Name of the sequence in the sequence list

• tracknr – Which track to use (1 or 2)

__getitem__(key: str) → Union[Callable[[...], Any], Parameter]

Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None

Prevent pickling instruments, and give a nice error message.

__repr__() → str

Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only. If your case is more complicated, you’re probably better off simply making a new method in your Instrument subclass definition.

Parameters

• name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.

• **kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[Type[ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

• name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.

• parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.

• **kwargs – Constructor arguments for parameter_class.

Raises

• KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.

• ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: Union[InstrumentModule, ChannelTuple]) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

• name – How the submodule will be stored within instrument.submodules and also how it can be addressed.

• submodule – The submodule to be stored.

Raises

• KeyError – If this instrument already contains a submodule with this name.

• TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: List[qcodes.instrument.instrument_base.InstrumentBase]

Returns a list of instruments, starting from the current instrument and following to the parent instrument and the parents parent instrument until the root instrument is reached.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

• func_name – The name of a function of this instrument.

• *args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']

A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []

A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters

param_name – The name of a parameter of this instrument.

Returns

The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters

metadata – Metadata to load.

property name: str

Name of the instrument This is equivalent to full_name for backwards compatibility.

property name_parts: List[str]

omit_delegate_attrs: List[str] = []

A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase

Returns the parent instrument. By default this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

• update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.

• max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: qcodes.instrument.instrument_base.InstrumentBase

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

• param_name – The name of a parameter of this instrument.

• value – The new value to set.

property short_name: str

Short name of the instrument

snapshot(update: Optional[bool] = False) → Dict[Any, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters

update – Passed to snapshot_base.

Returns

Base snapshot.

snapshot_base(update: Optional[bool] = False, params_to_skip_update: Optional[Sequence[str]] = None) → Dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

• update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.

• params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

dict

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters

verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

write_raw(cmd: str) → None

parameters: Dict[str, ParameterBase] = {}

All the parameters supported by this instrument. Usually populated via add_parameter().

functions: Dict[str, Function] = {}

All the functions supported by this instrument. Usually populated via add_function().

submodules: Dict[str, Union['InstrumentModule', 'ChannelTuple']] = {}

All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: Dict[str, 'InstrumentModule'] = {}

All the InstrumentModule of this instrument Usually populated via add_submodule().

class qcodes.instrument_drivers.tektronix.AWG70000A.AWG70000A(*args: Any, **kwargs: Any)

Bases: VisaInstrument

The QCoDeS driver for Tektronix AWG70000A series AWG’s.

The drivers for AWG70001A/AWG70001B and AWG70002A/AWG70002B should be subclasses of this general class.

Parameters

• name – The name used internally by QCoDeS in the DataSet

• address – The VISA resource name of the instrument

• timeout – The VISA timeout time (in seconds)

• num_channels – Number of channels on the AWG

force_triggerA() → None

Force a trigger A event

force_triggerB() → None

Force a trigger B event

wait_for_operation_to_complete() → None

Waits for the latest issued overlapping command to finish

play(wait_for_running: bool = True, timeout: float = 10) → None

Run the AWG/Func. Gen. This command is equivalent to pressing the play button on the front panel.

Parameters

• wait_for_running – If True, this command is blocking while the instrument is getting ready to play

• timeout – The maximal time to wait for the instrument to play. Raises an exception is this time is reached.

stop() → None

Stop the output of the instrument. This command is equivalent to pressing the stop button on the front panel.

property sequenceList: List[str]

Return the sequence list as a list of strings

property waveformList: List[str]

Return the waveform list as a list of strings

delete_sequence_from_list(seqname: str) → None

Delete the specified sequence from the sequence list

Parameters

seqname – The name of the sequence (as it appears in the sequence list, not the file name) to delete

clearSequenceList() → None

Clear the sequence list

clearWaveformList() → None

Clear the waveform list

static makeWFMXFile(data: ndarray, amplitude: float) → bytes

Compose a WFMX file

Parameters

• data – A numpy array holding the data. Markers can be included.

• amplitude – The peak-to-peak amplitude (V) assumed to be set on the channel that will play this waveform. This information is needed as the waveform must be rescaled to (-1, 1) where -1 will correspond to the channel’s min. voltage and 1 to the channel’s max. voltage.

Returns

The binary .wfmx file, ready to be sent to the instrument.

sendSEQXFile(seqx: bytes, filename: str, path: Optional[str] = None) → None

Send a binary seqx file to the AWG’s memory

Parameters

• seqx – The binary seqx file, preferably the output of makeSEQXFile.

• filename – The name of the file on the AWG disk, including the extension.

• path – The path to the directory where the file should be saved. If omitted, seqxFileFolder will be used.

sendWFMXFile(wfmx: bytes, filename: str, path: Optional[str] = None) → None

Send a binary wfmx file to the AWG’s memory

Parameters

• wfmx – The binary wfmx file, preferably the output of makeWFMXFile.

• filename – The name of the file on the AWG disk, including the extension.

• path – The path to the directory where the file should be saved. If omitted, seqxFileFolder will be used.

loadWFMXFile(filename: str, path: Optional[str] = None) → None

Loads a wfmx from memory into the waveform list Only loading from the C: drive is supported

Parameters

• filename – Name of the file (with extension)

• path – Path to load from. If omitted, the default path (self.wfmxFileFolder) is used.

loadSEQXFile(filename: str, path: Optional[str] = None) → None

Load a seqx file from instrument disk memory. All sequences in the file are loaded into the sequence list.

Parameters

• filename – The name of the sequence file INCLUDING the extension

• path – Path to load from. If omitted, the default path (self.seqxFileFolder) is used.

static make_SEQX_from_forged_sequence(seq: Dict[int, Dict[Any, Any]], amplitudes: List[float], seqname: str, channel_mapping: Optional[Dict[Union[str, int], int]] = None) → bytes

Make a .seqx from a forged broadbean sequence. Supports subsequences.

Parameters

• seq – The output of broadbean’s Sequence.forge()

• amplitudes – A list of the AWG channels’ voltage amplitudes. The first entry is ch1 etc.

• channel_mapping – A mapping from what the channel is called in the broadbean sequence to the integer describing the physical channel it should be assigned to.

• seqname – The name that the sequence will have in the AWG’s sequence list. Used for loading the sequence.

Returns

The binary .seqx file contents. Can be sent directly to the

instrument or saved on disk.

__del__() → None

Close the instrument and remove its instance record.

__getitem__(key: str) → Union[Callable[[...], Any], Parameter]

Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None

Prevent pickling instruments, and give a nice error message.

__repr__() → str

Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only. If your case is more complicated, you’re probably better off simply making a new method in your Instrument subclass definition.

Parameters

• name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.

• **kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[Type[ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

• name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.

• parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.

• **kwargs – Constructor arguments for parameter_class.

Raises

• KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.

• ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: Union[InstrumentModule, ChannelTuple]) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

• name – How the submodule will be stored within instrument.submodules and also how it can be addressed.

• submodule – The submodule to be stored.

Raises

• KeyError – If this instrument already contains a submodule with this name.

• TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: List[qcodes.instrument.instrument_base.InstrumentBase]

Returns a list of instruments, starting from the current instrument and following to the parent instrument and the parents parent instrument until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters

cmd – The string to send to the instrument.

Returns

response

Raises

Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters

cmd – The command to send to the instrument.

Returns

The instrument’s response.

Return type

str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

• func_name – The name of a function of this instrument.

• *args – any arguments to the function.

Returns

The return value of the function.

check_error(ret_code: int) → None

Default error checking, raises an error if return code !=0. Does not differentiate between warnings or specific error messages. Override this function in your driver if you want to add specific error messages.

Parameters

ret_code – A Visa error code. See eg: https://github.com/hgrecco/pyvisa/blob/master/pyvisa/errors.py

Raises

visa.VisaIOError – if ret_code indicates a communication problem.

close() → None

Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

• idn_param – Name of parameter that returns ID dict. Default IDN.

• begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']

A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []

A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None

Clear the buffers of the device

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

• name – Name of the instrument.

• instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[Type[T]] = None) → T

Find an existing instrument by name.

Parameters

• name – Name of the instrument.

• instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

• KeyError – If no instrument of that name was found, or if its reference is invalid (dead).

• TypeError – If a specific class was requested but a different type was found.

property full_name: str

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters

param_name – The name of a parameter of this instrument.

Returns

The current value of the parameter.

get_idn() → Dict[str, Optional[str]]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns

A dict containing vendor, model, serial, and firmware.

classmethod instances() → List[Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns

A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters

instr_instance – Instance of an Instrument class or its subclass.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters

metadata – Metadata to load.

static makeSEQXFile(trig_waits: Sequence[int], nreps: Sequence[int], event_jumps: Sequence[int], event_jump_to: Sequence[int], go_to: Sequence[int], wfms: Sequence[Sequence[ndarray]], amplitudes: Sequence[float], seqname: str, flags: Optional[Sequence[Sequence[Sequence[int]]]] = None) → bytes

Make a full .seqx file (bundle) A .seqx file can presumably hold several sequences, but for now we support only packing a single sequence

For a single sequence, a .seqx file is a bundle of two files and two folders:

/Sequences

sequence.sml

/Waveforms

wfm1.wfmx wfm2.wfmx …

setup.xml userNotes.txt

Parameters

• trig_waits – Wait for a trigger? If yes, you must specify the trigger input. 0 for off, 1 for ‘TrigA’, 2 for ‘TrigB’, 3 for ‘Internal’.

• nreps – No. of repetitions. 0 corresponds to infinite.

• event_jumps – Jump when event triggered? If yes, you must specify the trigger input. 0 for off, 1 for ‘TrigA’, 2 for ‘TrigB’, 3 for ‘Internal’.

• event_jump_to – Jump target in case of event. 1-indexed, 0 means next. Must be specified for all elements.

• go_to – Which element to play next. 1-indexed, 0 means next.

• wfms – numpy arrays describing each waveform plus two markers, packed like np.array([wfm, m1, m2]). These numpy arrays are then again packed in lists according to: [[wfmch1pos1, wfmch1pos2, …], [wfmch2pos1, …], …]

• amplitudes – The peak-to-peak amplitude in V of the channels, i.e. a list [ch1_amp, ch2_amp].

• seqname – The name of the sequence. This name will appear in the sequence list. Note that all spaces are converted to ‘_’

• flags – Flags for the auxiliary outputs. 0 for ‘No change’, 1 for ‘High’, 2 for ‘Low’, 3 for ‘Toggle’, or 4 for ‘Pulse’. 4 flags [A, B, C, D] for every channel in every element, packed like: [[ch1pos1, ch1pos2, …], [ch2pos1, …], …] If omitted, no flags will be set.

Returns

The binary .seqx file, ready to be sent to the instrument.

property name: str

Name of the instrument This is equivalent to full_name for backwards compatibility.

property name_parts: List[str]

omit_delegate_attrs: List[str] = []

A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: Optional[qcodes.instrument.instrument_base.InstrumentBase]

Returns the parent instrument. By default this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

• update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.

• max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters

instance – Instance to record.

Raises

KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters

instance – The instance to remove

property root_instrument: qcodes.instrument.instrument_base.InstrumentBase

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

• param_name – The name of a parameter of this instrument.

• value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters

address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: Optional[str]) → None

Change the read terminator to use.

Parameters

terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

shared_kwargs = ()

property short_name: str

Short name of the instrument

snapshot(update: Optional[bool] = False) → Dict[Any, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters

update – Passed to snapshot_base.

Returns

Base snapshot.

snapshot_base(update: Optional[bool] = True, params_to_skip_update: Optional[Sequence[str]] = None) → Dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

• update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.

• params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

dict

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters

verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters

cmd – The string to send to the instrument.

Raises

Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters

cmd – The command to send to the instrument.

parameters: Dict[str, ParameterBase] = {}

All the parameters supported by this instrument. Usually populated via add_parameter().

functions: Dict[str, Function] = {}

All the functions supported by this instrument. Usually populated via add_function().

submodules: Dict[str, Union['InstrumentModule', 'ChannelTuple']] = {}

All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: Dict[str, 'InstrumentModule'] = {}

All the InstrumentModule of this instrument Usually populated via add_submodule().

qcodes.instrument_drivers.tektronix.AWG70002A module

class qcodes.instrument_drivers.tektronix.AWG70002A.AWG70002A(*args: Any, **kwargs: Any)

Bases: AWG70000A

The QCoDeS driver for Tektronix AWG70002A series AWG’s.

All the actual driver meat is in the superclass AWG70000A.

Parameters

• name – The name used internally by QCoDeS in the DataSet

• address – The VISA resource name of the instrument

• timeout – The VISA timeout time (in seconds).

__del__() → None

Close the instrument and remove its instance record.

__getitem__(key: str) → Union[Callable[[...], Any], Parameter]

Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None

Prevent pickling instruments, and give a nice error message.

__repr__() → str

Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only. If your case is more complicated, you’re probably better off simply making a new method in your Instrument subclass definition.

Parameters

• name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.

• **kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[Type[ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

• name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.

• parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.

• **kwargs – Constructor arguments for parameter_class.

Raises

• KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.

• ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: Union[InstrumentModule, ChannelTuple]) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

• name – How the submodule will be stored within instrument.submodules and also how it can be addressed.

• submodule – The submodule to be stored.

Raises

• KeyError – If this instrument already contains a submodule with this name.

• TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: List[qcodes.instrument.instrument_base.InstrumentBase]

Returns a list of instruments, starting from the current instrument and following to the parent instrument and the parents parent instrument until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters

cmd – The string to send to the instrument.

Returns

response

Raises

Exception – Wraps any underlying exception with extra context, including the command and the instrument.

ask_raw(cmd: str) → str

Low-level interface to visa_handle.ask.

Parameters

cmd – The command to send to the instrument.

Returns

The instrument’s response.

Return type

str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

• func_name – The name of a function of this instrument.

• *args – any arguments to the function.

Returns

The return value of the function.

check_error(ret_code: int) → None

Default error checking, raises an error if return code !=0. Does not differentiate between warnings or specific error messages. Override this function in your driver if you want to add specific error messages.

Parameters

ret_code – A Visa error code. See eg: https://github.com/hgrecco/pyvisa/blob/master/pyvisa/errors.py

Raises

visa.VisaIOError – if ret_code indicates a communication problem.

clearSequenceList() → None

Clear the sequence list

clearWaveformList() → None

Clear the waveform list

close() → None

Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

• idn_param – Name of parameter that returns ID dict. Default IDN.

• begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']

A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []

A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

delete_sequence_from_list(seqname: str) → None

Delete the specified sequence from the sequence list

Parameters

seqname – The name of the sequence (as it appears in the sequence list, not the file name) to delete

device_clear() → None

Clear the buffers of the device

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

• name – Name of the instrument.

• instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[Type[T]] = None) → T

Find an existing instrument by name.

Parameters

• name – Name of the instrument.

• instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

• KeyError – If no instrument of that name was found, or if its reference is invalid (dead).

• TypeError – If a specific class was requested but a different type was found.

force_triggerA() → None

Force a trigger A event

force_triggerB() → None

Force a trigger B event

property full_name: str

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters

param_name – The name of a parameter of this instrument.

Returns

The current value of the parameter.

get_idn() → Dict[str, Optional[str]]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns

A dict containing vendor, model, serial, and firmware.

classmethod instances() → List[Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns

A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters

instr_instance – Instance of an Instrument class or its subclass.

loadSEQXFile(filename: str, path: Optional[str] = None) → None

Load a seqx file from instrument disk memory. All sequences in the file are loaded into the sequence list.

Parameters

• filename – The name of the sequence file INCLUDING the extension

• path – Path to load from. If omitted, the default path (self.seqxFileFolder) is used.

loadWFMXFile(filename: str, path: Optional[str] = None) → None

Loads a wfmx from memory into the waveform list Only loading from the C: drive is supported

Parameters

• filename – Name of the file (with extension)

• path – Path to load from. If omitted, the default path (self.wfmxFileFolder) is used.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters

metadata – Metadata to load.

static makeSEQXFile(trig_waits: Sequence[int], nreps: Sequence[int], event_jumps: Sequence[int], event_jump_to: Sequence[int], go_to: Sequence[int], wfms: Sequence[Sequence[ndarray]], amplitudes: Sequence[float], seqname: str, flags: Optional[Sequence[Sequence[Sequence[int]]]] = None) → bytes

Make a full .seqx file (bundle) A .seqx file can presumably hold several sequences, but for now we support only packing a single sequence

For a single sequence, a .seqx file is a bundle of two files and two folders:

/Sequences

sequence.sml

/Waveforms

wfm1.wfmx wfm2.wfmx …

setup.xml userNotes.txt

Parameters

• trig_waits – Wait for a trigger? If yes, you must specify the trigger input. 0 for off, 1 for ‘TrigA’, 2 for ‘TrigB’, 3 for ‘Internal’.

• nreps – No. of repetitions. 0 corresponds to infinite.

• event_jumps – Jump when event triggered? If yes, you must specify the trigger input. 0 for off, 1 for ‘TrigA’, 2 for ‘TrigB’, 3 for ‘Internal’.

• event_jump_to – Jump target in case of event. 1-indexed, 0 means next. Must be specified for all elements.

• go_to – Which element to play next. 1-indexed, 0 means next.

• wfms – numpy arrays describing each waveform plus two markers, packed like np.array([wfm, m1, m2]). These numpy arrays are then again packed in lists according to: [[wfmch1pos1, wfmch1pos2, …], [wfmch2pos1, …], …]

• amplitudes – The peak-to-peak amplitude in V of the channels, i.e. a list [ch1_amp, ch2_amp].

• seqname – The name of the sequence. This name will appear in the sequence list. Note that all spaces are converted to ‘_’

• flags – Flags for the auxiliary outputs. 0 for ‘No change’, 1 for ‘High’, 2 for ‘Low’, 3 for ‘Toggle’, or 4 for ‘Pulse’. 4 flags [A, B, C, D] for every channel in every element, packed like: [[ch1pos1, ch1pos2, …], [ch2pos1, …], …] If omitted, no flags will be set.

Returns

The binary .seqx file, ready to be sent to the instrument.

static makeWFMXFile(data: ndarray, amplitude: float) → bytes

Compose a WFMX file

Parameters

• data – A numpy array holding the data. Markers can be included.

• amplitude – The peak-to-peak amplitude (V) assumed to be set on the channel that will play this waveform. This information is needed as the waveform must be rescaled to (-1, 1) where -1 will correspond to the channel’s min. voltage and 1 to the channel’s max. voltage.

Returns

The binary .wfmx file, ready to be sent to the instrument.

static make_SEQX_from_forged_sequence(seq: Dict[int, Dict[Any, Any]], amplitudes: List[float], seqname: str, channel_mapping: Optional[Dict[Union[str, int], int]] = None) → bytes

Make a .seqx from a forged broadbean sequence. Supports subsequences.

Parameters

• seq – The output of broadbean’s Sequence.forge()

• amplitudes – A list of the AWG channels’ voltage amplitudes. The first entry is ch1 etc.

• channel_mapping – A mapping from what the channel is called in the broadbean sequence to the integer describing the physical channel it should be assigned to.

• seqname – The name that the sequence will have in the AWG’s sequence list. Used for loading the sequence.

Returns

The binary .seqx file contents. Can be sent directly to the

instrument or saved on disk.

property name: str

Name of the instrument This is equivalent to full_name for backwards compatibility.

property name_parts: List[str]

omit_delegate_attrs: List[str] = []

A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: Optional[qcodes.instrument.instrument_base.InstrumentBase]

Returns the parent instrument. By default this is None. Any SubInstrument should subclass this to return the parent instrument.

play(wait_for_running: bool = True, timeout: float = 10) → None

Run the AWG/Func. Gen. This command is equivalent to pressing the play button on the front panel.

Parameters

• wait_for_running – If True, this command is blocking while the instrument is getting ready to play

• timeout – The maximal time to wait for the instrument to play. Raises an exception is this time is reached.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

• update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.

• max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters

instance – Instance to record.

Raises

KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters

instance – The instance to remove

property root_instrument: qcodes.instrument.instrument_base.InstrumentBase

sendSEQXFile(seqx: bytes, filename: str, path: Optional[str] = None) → None

Send a binary seqx file to the AWG’s memory

Parameters

• seqx – The binary seqx file, preferably the output of makeSEQXFile.

• filename – The name of the file on the AWG disk, including the extension.

• path – The path to the directory where the file should be saved. If omitted, seqxFileFolder will be used.

sendWFMXFile(wfmx: bytes, filename: str, path: Optional[str] = None) → None

Send a binary wfmx file to the AWG’s memory

Parameters

• wfmx – The binary wfmx file, preferably the output of makeWFMXFile.

• filename – The name of the file on the AWG disk, including the extension.

• path – The path to the directory where the file should be saved. If omitted, seqxFileFolder will be used.

property sequenceList: List[str]

Return the sequence list as a list of strings

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

• param_name – The name of a parameter of this instrument.

• value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters

address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: Optional[str]) → None

Change the read terminator to use.

Parameters

terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

shared_kwargs = ()

property short_name: str

Short name of the instrument

snapshot(update: Optional[bool] = False) → Dict[Any, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters

update – Passed to snapshot_base.

Returns

Base snapshot.

snapshot_base(update: Optional[bool] = True, params_to_skip_update: Optional[Sequence[str]] = None) → Dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

• update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.

• params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

dict

stop() → None

Stop the output of the instrument. This command is equivalent to pressing the stop button on the front panel.

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters

verbose – If True, then information about the parameters that are being check is printed.

wait_for_operation_to_complete() → None

Waits for the latest issued overlapping command to finish

property waveformList: List[str]

Return the waveform list as a list of strings

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters

cmd – The string to send to the instrument.

Raises

Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters

cmd – The command to send to the instrument.

visabackend: str = str

visa_handle: visa.resources.MessageBasedResource = visa.resources.MessageBasedResource

visalib: Optional[str] = visalib

parameters: Dict[str, ParameterBase] = {}

All the parameters supported by this instrument. Usually populated via add_parameter().

functions: Dict[str, Function] = {}

All the functions supported by this instrument. Usually populated via add_function().

submodules: Dict[str, Union['InstrumentModule', 'ChannelTuple']] = {}

All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: Dict[str, 'InstrumentModule'] = {}

All the InstrumentModule of this instrument Usually populated via add_submodule().

metadata: Dict[str, Any] = {}

qcodes.instrument_drivers.tektronix.AWGFileParser module

qcodes.instrument_drivers.tektronix.AWGFileParser.parse_awg_file(awgfilepath: str) → Tuple[Tuple[List[List[Dict[Any, Any]]], List[List[Dict[Any, Any]]], List[List[Dict[Any, Any]]], List[Union[str, int]], List[Union[str, int]], List[Union[str, int]], List[Union[str, int]], List[int]], Dict[str, Union[str, int, Tuple[Any, ...]]]]

Parser for a binary .awg file. Returns a tuple matching the call signature of make_send_and_load_awg_file and a dictionary with instrument settings

NOTE: Build-in waveforms are not stored in .awg files. Blame tektronix.

Parameters

awgfilepath – The absolute path to the awg file

Returns

A tuple and a dict, where the tuple is (wfms, m1s, m2s, nreps, trigs, gotos, jumps, channels) and the dict contains all instrument settings from the file

qcodes.instrument_drivers.tektronix.DPO7200xx module

QCoDeS driver for the MSO/DPO5000/B, DPO7000/C, DPO70000/B/C/D/DX/SX, DSA70000/B/C/D, and MSO70000/C/DX Series Digital Oscilloscopes

qcodes.instrument_drivers.tektronix.DPO7200xx.strip_quotes(string: str) → str

This function is used as a get_parser for various parameters in this driver

exception qcodes.instrument_drivers.tektronix.DPO7200xx.ModeError

Bases: Exception

Raise this exception if we are in a wrong mode to perform an action

args

with_traceback()

Exception.with_traceback(tb) – set self.__traceback__ to tb and return self.

class qcodes.instrument_drivers.tektronix.DPO7200xx.TektronixDPO7000xx(*args: Any, **kwargs: Any)

Bases: VisaInstrument

QCoDeS driver for the MSO/DPO5000/B, DPO7000/C, DPO70000/B/C/D/DX/SX, DSA70000/B/C/D, and MSO70000/C/DX Series Digital Oscilloscopes

number_of_channels = 4

number_of_measurements = 8

ask_raw(cmd: str) → str

Sometimes the instrument returns non-ascii characters in response strings manually adjust the encoding to latin-1

__del__() → None

Close the instrument and remove its instance record.

__getitem__(key: str) → Union[Callable[[...], Any], Parameter]

Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None

Prevent pickling instruments, and give a nice error message.

__repr__() → str

Simplified repr giving just the class and name.

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only. If your case is more complicated, you’re probably better off simply making a new method in your Instrument subclass definition.

Parameters

• name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.

• **kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[Type[ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

• name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.

• parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.

• **kwargs – Constructor arguments for parameter_class.

Raises

• KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.

• ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: Union[InstrumentModule, ChannelTuple]) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

• name – How the submodule will be stored within instrument.submodules and also how it can be addressed.

• submodule – The submodule to be stored.

Raises

• KeyError – If this instrument already contains a submodule with this name.

• TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: List[qcodes.instrument.instrument_base.InstrumentBase]

Returns a list of instruments, starting from the current instrument and following to the parent instrument and the parents parent instrument until the root instrument is reached.

ask(cmd: str) → str

Write a command string to the hardware and return a response.

Subclasses that transform cmd should override this method, and in it call super().ask(new_cmd). Subclasses that define a new hardware communication should instead override ask_raw.

Parameters

cmd – The string to send to the instrument.

Returns

response

Raises

Exception – Wraps any underlying exception with extra context, including the command and the instrument.

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

• func_name – The name of a function of this instrument.

• *args – any arguments to the function.

Returns

The return value of the function.

check_error(ret_code: int) → None

Default error checking, raises an error if return code !=0. Does not differentiate between warnings or specific error messages. Override this function in your driver if you want to add specific error messages.

Parameters

ret_code – A Visa error code. See eg: https://github.com/hgrecco/pyvisa/blob/master/pyvisa/errors.py

Raises

visa.VisaIOError – if ret_code indicates a communication problem.

close() → None

Disconnect and irreversibly tear down the instrument.

classmethod close_all() → None

Try to close all instruments registered in _all_instruments This is handy for use with atexit to ensure that all instruments are closed when a python session is closed.

Examples

>>> atexit.register(qc.Instrument.close_all())

connect_message(idn_param: str = 'IDN', begin_time: Optional[float] = None) → None

Print a standard message on initial connection to an instrument.

Parameters

• idn_param – Name of parameter that returns ID dict. Default IDN.

• begin_time – time.time() when init started. Default is self._t0, set at start of Instrument.__init__.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']

A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []

A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

device_clear() → None

Clear the buffers of the device

static exist(name: str, instrument_class: Optional[type] = None) → bool

Check if an instrument with a given names exists (i.e. is already instantiated).

Parameters

• name – Name of the instrument.

• instrument_class – The type of instrument you are looking for.

classmethod find_instrument(name: str, instrument_class: Optional[Type[T]] = None) → T

Find an existing instrument by name.

Parameters

• name – Name of the instrument.

• instrument_class – The type of instrument you are looking for.

Returns

The instrument found.

Raises

• KeyError – If no instrument of that name was found, or if its reference is invalid (dead).

• TypeError – If a specific class was requested but a different type was found.

property full_name: str

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters

param_name – The name of a parameter of this instrument.

Returns

The current value of the parameter.

get_idn() → Dict[str, Optional[str]]

Parse a standard VISA *IDN? response into an ID dict.

Even though this is the VISA standard, it applies to various other types as well, such as IPInstruments, so it is included here in the Instrument base class.

Override this if your instrument does not support *IDN? or returns a nonstandard IDN string. This string is supposed to be a comma-separated list of vendor, model, serial, and firmware, but semicolon and colon are also common separators so we accept them here as well.

Returns

A dict containing vendor, model, serial, and firmware.

classmethod instances() → List[Instrument]

Get all currently defined instances of this instrument class.

You can use this to get the objects back if you lose track of them, and it’s also used by the test system to find objects to test against.

Returns

A list of instances.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

static is_valid(instr_instance: Instrument) → bool

Check if a given instance of an instrument is valid: if an instrument has been closed, its instance is not longer a “valid” instrument.

Parameters

instr_instance – Instance of an Instrument class or its subclass.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters

metadata – Metadata to load.

property name: str

Name of the instrument This is equivalent to full_name for backwards compatibility.

property name_parts: List[str]

omit_delegate_attrs: List[str] = []

A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: Optional[qcodes.instrument.instrument_base.InstrumentBase]

Returns the parent instrument. By default this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

• update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.

• max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

classmethod record_instance(instance: Instrument) → None

Record (a weak ref to) an instance in a class’s instance list.

Also records the instance in list of all instruments, and verifies that there are no other instruments with the same name.

This method is called after initialization of the instrument is completed.

Parameters

instance – Instance to record.

Raises

KeyError – If another instance with the same name is already present.

classmethod remove_instance(instance: Instrument) → None

Remove a particular instance from the record.

Parameters

instance – The instance to remove

property root_instrument: qcodes.instrument.instrument_base.InstrumentBase

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

• param_name – The name of a parameter of this instrument.

• value – The new value to set.

set_address(address: str) → None

Set the address for this instrument.

Parameters

address – The visa resource name to use to connect. The address should be the actual address and just that. If you wish to change the backend for VISA, use the self.visalib attribute (and then call this function).

set_terminator(terminator: Optional[str]) → None

Change the read terminator to use.

Parameters

terminator – Character(s) to look for at the end of a read and to end each write command with. eg. \r\n. If None the terminator will not be set.

shared_kwargs = ()

property short_name: str

Short name of the instrument

snapshot(update: Optional[bool] = False) → Dict[Any, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters

update – Passed to snapshot_base.

Returns

Base snapshot.

snapshot_base(update: Optional[bool] = True, params_to_skip_update: Optional[Sequence[str]] = None) → Dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

• update – If True, update the state by querying the instrument. If None only update if the state is known to be invalid. If False, just use the latest values in memory and never update.

• params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

dict

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters

verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

Write a command string with NO response to the hardware.

Subclasses that transform cmd should override this method, and in it call super().write(new_cmd). Subclasses that define a new hardware communication should instead override write_raw.

Parameters

cmd – The string to send to the instrument.

Raises

Exception – Wraps any underlying exception with extra context, including the command and the instrument.

write_raw(cmd: str) → None

Low-level interface to visa_handle.write.

Parameters

cmd – The command to send to the instrument.

parameters: Dict[str, ParameterBase] = {}

All the parameters supported by this instrument. Usually populated via add_parameter().

functions: Dict[str, Function] = {}

All the functions supported by this instrument. Usually populated via add_function().

submodules: Dict[str, Union['InstrumentModule', 'ChannelTuple']] = {}

All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: Dict[str, 'InstrumentModule'] = {}

All the InstrumentModule of this instrument Usually populated via add_submodule().

class qcodes.instrument_drivers.tektronix.DPO7200xx.TektronixDPOData(parent: Union[Instrument, InstrumentChannel], name: str)

Bases: InstrumentChannel

This submodule sets and retrieves information regarding the data source for the “CURVE?” query, which is used when retrieving waveform data.

__getitem__(key: str) → Union[Callable[[...], Any], Parameter]

Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None

Prevent pickling instruments, and give a nice error message.

__repr__() → str

Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only. If your case is more complicated, you’re probably better off simply making a new method in your Instrument subclass definition.

Parameters

• name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.

• **kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[Type[ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

• name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.

• parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.

• **kwargs – Constructor arguments for parameter_class.

Raises

• KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.

• ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: Union[InstrumentModule, ChannelTuple]) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

• name – How the submodule will be stored within instrument.submodules and also how it can be addressed.

• submodule – The submodule to be stored.

Raises

• KeyError – If this instrument already contains a submodule with this name.

• TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: List[qcodes.instrument.instrument_base.InstrumentBase]

Returns a list of instruments, starting from the current instrument and following to the parent instrument and the parents parent instrument until the root instrument is reached.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

• func_name – The name of a function of this instrument.

• *args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']

A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []

A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters

param_name – The name of a parameter of this instrument.

Returns

The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters

metadata – Metadata to load.

property name: str

Name of the instrument This is equivalent to full_name for backwards compatibility.

property name_parts: List[str]

omit_delegate_attrs: List[str] = []

A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase

Returns the parent instrument. By default this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

• update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.

• max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: qcodes.instrument.instrument_base.InstrumentBase

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

• param_name – The name of a parameter of this instrument.

• value – The new value to set.

property short_name: str

Short name of the instrument

snapshot(update: Optional[bool] = False) → Dict[Any, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters

update – Passed to snapshot_base.

Returns

Base snapshot.

snapshot_base(update: Optional[bool] = False, params_to_skip_update: Optional[Sequence[str]] = None) → Dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

• update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.

• params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

dict

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters

verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

write_raw(cmd: str) → None

parameters: Dict[str, ParameterBase] = {}

All the parameters supported by this instrument. Usually populated via add_parameter().

functions: Dict[str, Function] = {}

All the functions supported by this instrument. Usually populated via add_function().

submodules: Dict[str, Union['InstrumentModule', 'ChannelTuple']] = {}

All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: Dict[str, 'InstrumentModule'] = {}

All the InstrumentModule of this instrument Usually populated via add_submodule().

class qcodes.instrument_drivers.tektronix.DPO7200xx.TekronixDPOWaveform(parent: Union[Instrument, InstrumentChannel], name: str, identifier: str)

Bases: InstrumentChannel

This submodule retrieves data from waveform sources, e.g. channels.

valid_identifiers = ['CH1', 'CH2', 'CH3', 'CH4', 'MATH1', 'MATH2', 'MATH3', 'MATH4', 'REF1', 'REF2', 'REF3', 'REF4']

__getitem__(key: str) → Union[Callable[[...], Any], Parameter]

Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None

Prevent pickling instruments, and give a nice error message.

__repr__() → str

Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only. If your case is more complicated, you’re probably better off simply making a new method in your Instrument subclass definition.

Parameters

• name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.

• **kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[Type[ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

• name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.

• parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.

• **kwargs – Constructor arguments for parameter_class.

Raises

• KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.

• ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: Union[InstrumentModule, ChannelTuple]) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

• name – How the submodule will be stored within instrument.submodules and also how it can be addressed.

• submodule – The submodule to be stored.

Raises

• KeyError – If this instrument already contains a submodule with this name.

• TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: List[qcodes.instrument.instrument_base.InstrumentBase]

Returns a list of instruments, starting from the current instrument and following to the parent instrument and the parents parent instrument until the root instrument is reached.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

• func_name – The name of a function of this instrument.

• *args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']

A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []

A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters

param_name – The name of a parameter of this instrument.

Returns

The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters

metadata – Metadata to load.

property name: str

Name of the instrument This is equivalent to full_name for backwards compatibility.

property name_parts: List[str]

omit_delegate_attrs: List[str] = []

A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase

Returns the parent instrument. By default this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

• update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.

• max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: qcodes.instrument.instrument_base.InstrumentBase

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

• param_name – The name of a parameter of this instrument.

• value – The new value to set.

property short_name: str

Short name of the instrument

snapshot(update: Optional[bool] = False) → Dict[Any, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters

update – Passed to snapshot_base.

Returns

Base snapshot.

snapshot_base(update: Optional[bool] = False, params_to_skip_update: Optional[Sequence[str]] = None) → Dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

• update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.

• params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

dict

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters

verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

write_raw(cmd: str) → None

parameters: Dict[str, ParameterBase] = {}

All the parameters supported by this instrument. Usually populated via add_parameter().

functions: Dict[str, Function] = {}

All the functions supported by this instrument. Usually populated via add_function().

submodules: Dict[str, Union['InstrumentModule', 'ChannelTuple']] = {}

All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: Dict[str, 'InstrumentModule'] = {}

All the InstrumentModule of this instrument Usually populated via add_submodule().

class qcodes.instrument_drivers.tektronix.DPO7200xx.TektronixDPOWaveformFormat(parent: Union[Instrument, InstrumentChannel], name: str)

Bases: InstrumentChannel

With this sub module we can query waveform formatting data. Please note that parameters defined in this submodule effects all waveform sources, whereas parameters defined in the submodule ‘TekronixDPOWaveform’ apply to specific waveform sources (e.g. channel1 or math2)

__getitem__(key: str) → Union[Callable[[...], Any], Parameter]

Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None

Prevent pickling instruments, and give a nice error message.

__repr__() → str

Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only. If your case is more complicated, you’re probably better off simply making a new method in your Instrument subclass definition.

Parameters

• name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.

• **kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[Type[ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

• name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.

• parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.

• **kwargs – Constructor arguments for parameter_class.

Raises

• KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.

• ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: Union[InstrumentModule, ChannelTuple]) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

• name – How the submodule will be stored within instrument.submodules and also how it can be addressed.

• submodule – The submodule to be stored.

Raises

• KeyError – If this instrument already contains a submodule with this name.

• TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: List[qcodes.instrument.instrument_base.InstrumentBase]

Returns a list of instruments, starting from the current instrument and following to the parent instrument and the parents parent instrument until the root instrument is reached.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

• func_name – The name of a function of this instrument.

• *args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']

A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []

A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters

param_name – The name of a parameter of this instrument.

Returns

The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters

metadata – Metadata to load.

property name: str

Name of the instrument This is equivalent to full_name for backwards compatibility.

property name_parts: List[str]

omit_delegate_attrs: List[str] = []

A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase

Returns the parent instrument. By default this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

• update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.

• max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: qcodes.instrument.instrument_base.InstrumentBase

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

• param_name – The name of a parameter of this instrument.

• value – The new value to set.

property short_name: str

Short name of the instrument

snapshot(update: Optional[bool] = False) → Dict[Any, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters

update – Passed to snapshot_base.

Returns

Base snapshot.

snapshot_base(update: Optional[bool] = False, params_to_skip_update: Optional[Sequence[str]] = None) → Dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

• update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.

• params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

dict

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters

verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

write_raw(cmd: str) → None

parameters: Dict[str, ParameterBase] = {}

All the parameters supported by this instrument. Usually populated via add_parameter().

functions: Dict[str, Function] = {}

All the functions supported by this instrument. Usually populated via add_function().

submodules: Dict[str, Union['InstrumentModule', 'ChannelTuple']] = {}

All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: Dict[str, 'InstrumentModule'] = {}

All the InstrumentModule of this instrument Usually populated via add_submodule().

class qcodes.instrument_drivers.tektronix.DPO7200xx.TektronixDPOChannel(parent: Union[Instrument, InstrumentChannel], name: str, channel_number: int)

Bases: InstrumentChannel

The main channel module for the oscilloscope. The parameters defined here reflect the waveforms as they are displayed on the instrument display.

set_trace_length(value: int) → None

Set the trace length when retrieving data through the ‘waveform’ interface

Parameters

value – The requested number of samples in the trace

set_trace_time(value: float) → None

Parameters

value – The time over which a trace is desired.

__getitem__(key: str) → Union[Callable[[...], Any], Parameter]

Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None

Prevent pickling instruments, and give a nice error message.

__repr__() → str

Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only. If your case is more complicated, you’re probably better off simply making a new method in your Instrument subclass definition.

Parameters

• name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.

• **kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[Type[ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

• name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.

• parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.

• **kwargs – Constructor arguments for parameter_class.

Raises

• KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.

• ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: Union[InstrumentModule, ChannelTuple]) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

• name – How the submodule will be stored within instrument.submodules and also how it can be addressed.

• submodule – The submodule to be stored.

Raises

• KeyError – If this instrument already contains a submodule with this name.

• TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: List[qcodes.instrument.instrument_base.InstrumentBase]

Returns a list of instruments, starting from the current instrument and following to the parent instrument and the parents parent instrument until the root instrument is reached.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

• func_name – The name of a function of this instrument.

• *args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']

A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []

A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters

param_name – The name of a parameter of this instrument.

Returns

The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters

metadata – Metadata to load.

property name: str

Name of the instrument This is equivalent to full_name for backwards compatibility.

property name_parts: List[str]

omit_delegate_attrs: List[str] = []

A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase

Returns the parent instrument. By default this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

• update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.

• max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: qcodes.instrument.instrument_base.InstrumentBase

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

• param_name – The name of a parameter of this instrument.

• value – The new value to set.

property short_name: str

Short name of the instrument

snapshot(update: Optional[bool] = False) → Dict[Any, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters

update – Passed to snapshot_base.

Returns

Base snapshot.

snapshot_base(update: Optional[bool] = False, params_to_skip_update: Optional[Sequence[str]] = None) → Dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

• update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.

• params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

dict

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters

verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

write_raw(cmd: str) → None

parameters: Dict[str, ParameterBase] = {}

All the parameters supported by this instrument. Usually populated via add_parameter().

functions: Dict[str, Function] = {}

All the functions supported by this instrument. Usually populated via add_function().

submodules: Dict[str, Union['InstrumentModule', 'ChannelTuple']] = {}

All the submodules of this instrument such as channel lists or logical groupings of parameters. Usually populated via add_submodule().

instrument_modules: Dict[str, 'InstrumentModule'] = {}

All the InstrumentModule of this instrument Usually populated via add_submodule().

class qcodes.instrument_drivers.tektronix.DPO7200xx.TektronixDPOHorizontal(parent: Union[Instrument, InstrumentChannel], name: str)

Bases: InstrumentChannel

This module controls the horizontal axis of the scope

__getitem__(key: str) → Union[Callable[[...], Any], Parameter]

Delegate instrument[‘name’] to parameter or function ‘name’.

__getstate__() → None

Prevent pickling instruments, and give a nice error message.

__repr__() → str

Custom repr to give parent information

add_function(name: str, **kwargs: Any) → None

Bind one Function to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real function of the instrument.

This functionality is meant for simple cases, principally things that map to simple commands like *RST (reset) or those with just a few arguments. It requires a fixed argument count, and positional args only. If your case is more complicated, you’re probably better off simply making a new method in your Instrument subclass definition.

Parameters

• name – How the Function will be stored within instrument.Functions and also how you address it using the shortcut methods: instrument.call(func_name, *args) etc.

• **kwargs – constructor kwargs for Function

Raises

KeyError – If this instrument already has a function with this name.

add_parameter(name: str, parameter_class: Optional[Type[ParameterBase]] = None, **kwargs: Any) → None

Bind one Parameter to this instrument.

Instrument subclasses can call this repeatedly in their __init__ for every real parameter of the instrument.

In this sense, parameters are the state variables of the instrument, anything the user can set and/or get.

Parameters

• name – How the parameter will be stored within parameters and also how you address it using the shortcut methods: instrument.set(param_name, value) etc.

• parameter_class – You can construct the parameter out of any class. Default parameters.Parameter.

• **kwargs – Constructor arguments for parameter_class.

Raises

• KeyError – If this instrument already has a parameter with this name and the parameter being replaced is not an abstract parameter.

• ValueError – If there is an existing abstract parameter and the unit of the new parameter is inconsistent with the existing one.

add_submodule(name: str, submodule: Union[InstrumentModule, ChannelTuple]) → None

Bind one submodule to this instrument.

Instrument subclasses can call this repeatedly in their __init__ method for every submodule of the instrument.

Submodules can effectively be considered as instruments within the main instrument, and should at minimum be snapshottable. For example, they can be used to either store logical groupings of parameters, which may or may not be repeated, or channel lists. They should either be an instance of an InstrumentModule or a ChannelTuple.

Parameters

• name – How the submodule will be stored within instrument.submodules and also how it can be addressed.

• submodule – The submodule to be stored.

Raises

• KeyError – If this instrument already contains a submodule with this name.

• TypeError – If the submodule that we are trying to add is not an instance of an Metadatable object.

property ancestors: List[qcodes.instrument.instrument_base.InstrumentBase]

Returns a list of instruments, starting from the current instrument and following to the parent instrument and the parents parent instrument until the root instrument is reached.

ask(cmd: str) → str

ask_raw(cmd: str) → str

call(func_name: str, *args: Any) → Any

Shortcut for calling a function from its name.

Parameters

• func_name – The name of a function of this instrument.

• *args – any arguments to the function.

Returns

The return value of the function.

delegate_attr_dicts: List[str] = ['parameters', 'functions', 'submodules']

A list of names (strings) of dictionaries which are (or will be) attributes of self, whose keys should be treated as attributes of self.

delegate_attr_objects: List[str] = []

A list of names (strings) of objects which are (or will be) attributes of self, whose attributes should be passed through to self.

property full_name: str

get(param_name: str) → Any

Shortcut for getting a parameter from its name.

Parameters

param_name – The name of a parameter of this instrument.

Returns

The current value of the parameter.

invalidate_cache() → None

Invalidate the cache of all parameters on the instrument. Calling this method will recursively mark the cache of all parameters on the instrument and any parameter on instrument modules as invalid.

This is useful if you have performed manual operations (e.g. using the frontpanel) which changes the state of the instrument outside QCoDeS.

This in turn means that the next snapshot of the instrument will trigger a (potentially slow) reread of all parameters of the instrument if you pass update=None to snapshot.

load_metadata(metadata: Mapping[str, Any]) → None

Load metadata into this classes metadata dictionary.

Parameters

metadata – Metadata to load.

property name: str

Name of the instrument This is equivalent to full_name for backwards compatibility.

property name_parts: List[str]

omit_delegate_attrs: List[str] = []

A list of attribute names (strings) to not delegate to any other dictionary or object.

property parent: qcodes.instrument.instrument_base.InstrumentBase

Returns the parent instrument. By default this is None. Any SubInstrument should subclass this to return the parent instrument.

print_readable_snapshot(update: bool = False, max_chars: int = 80) → None

Prints a readable version of the snapshot. The readable snapshot includes the name, value and unit of each parameter. A convenience function to quickly get an overview of the status of an instrument.

Parameters

• update – If True, update the state by querying the instrument. If False, just use the latest values in memory. This argument gets passed to the snapshot function.

• max_chars – the maximum number of characters per line. The readable snapshot will be cropped if this value is exceeded. Defaults to 80 to be consistent with default terminal width.

property root_instrument: qcodes.instrument.instrument_base.InstrumentBase

set(param_name: str, value: Any) → None

Shortcut for setting a parameter from its name and new value.

Parameters

• param_name – The name of a parameter of this instrument.

• value – The new value to set.

property short_name: str

Short name of the instrument

snapshot(update: Optional[bool] = False) → Dict[Any, Any]

Decorate a snapshot dictionary with metadata. DO NOT override this method if you want metadata in the snapshot instead, override snapshot_base().

Parameters

update – Passed to snapshot_base.

Returns

Base snapshot.

snapshot_base(update: Optional[bool] = False, params_to_skip_update: Optional[Sequence[str]] = None) → Dict[Any, Any]

State of the instrument as a JSON-compatible dict (everything that the custom JSON encoder class NumpyJSONEncoder supports).

Parameters

• update – If True, update the state by querying the instrument. If None update the state if known to be invalid. If False, just use the latest values in memory and never update state.

• params_to_skip_update – List of parameter names that will be skipped in update even if update is True. This is useful if you have parameters that are slow to update but can be updated in a different way (as in the qdac). If you want to skip the update of certain parameters in all snapshots, use the snapshot_get attribute of those parameters instead.

Returns

base snapshot

Return type

dict

validate_status(verbose: bool = False) → None

Validate the values of all gettable parameters

The validation is done for all parameters that have both a get and set method.

Parameters

verbose – If True, then information about the parameters that are being check is printed.

write(cmd: str) → None

write_raw(cmd: str) → None

parameters: Dict[str, ParameterBase] = {}

All the parameters supported by this instrument. Usually populated via add_parameter().

functions: