pylablib.devices.Cryomagnetics package

Submodules

pylablib.devices.Cryomagnetics.base module

exception pylablib.devices.Cryomagnetics.base.CryomagneticsError[source]

Bases: pylablib.core.devio.base.DeviceError

Generic Cryomagnetics devices error

args
with_traceback()

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

exception pylablib.devices.Cryomagnetics.base.CryomagneticsBackendError(exc)[source]

Bases: pylablib.devices.Cryomagnetics.base.CryomagneticsError, pylablib.core.devio.comm_backend.DeviceBackendError

Generic Cryomagnetics backend communication error

args
with_traceback()

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

class pylablib.devices.Cryomagnetics.base.LM500(conn)[source]

Bases: pylablib.core.devio.SCPI.SCPIDevice

Cryomagnetics LM500/510 level monitor.

Channels are enumerated from 1. To abort filling or reset a timeout, call SCPIDevice.reset() method.

Parameters:conn – serial connection parameters (usually port or a tuple containing port and baudrate)
Error

alias of CryomagneticsError

ReraiseError

alias of CryomagneticsBackendError

close()[source]

Close connection to the device

get_channel()[source]

Get current measurement channel

select_channel(channel=1)[source]

Select the current measurement channel

get_type(channel=None)[source]

Get type of a given channel ("lhe" or "ln")

get_mode(channel=None)[source]

Get measurement mode at the given channel (None for the currently selected channel).

Can be either 'sample_hold', or 'continuous'.

set_mode(mode, channel=None)[source]

Set measurement mode at the given channel (None for the current channel).

Can be either 'sample_hold', or 'continuous'.

get_interval(channel=None)[source]

Get measurement interval (in seconds) in sample/hold mode at the given channel (None for the current channel)

set_interval(intvl, channel=None)[source]

Set measurement interval (in seconds) in sample/hold mode at the given channel (None for the current channel)

start_measurement(channel=None)[source]

Initialize measurement on a given channel

wait_for_measurement(channel=None, timeout=None)[source]

Wait for the measurement on a given channel to finish

get_level(channel=None)[source]

Get level reading on a given channel

measure_level(channel=None)[source]

Measure the level (perform the measurement and return the result) on a given channel

start_fill(channel=None)[source]

Initialize filling at a given channel (None for the current channel)

get_fill_status(channel=None)[source]

Get filling status at a given channels (None for the current channel).

Return either "off" (filling is off), "timeout" (filling timed out) or a float (time since filling started, in seconds).

get_low_level(channel=None)[source]

Get low level (automated refill start) setting on a given channel (None for the current channel)

set_low_level(level, channel=None)[source]

Set low level (automated refill start) setting on a given channel (None for the current channel)

get_high_level(channel=None)[source]

Get high level (automated refill stop) setting on a given channel (None for the current channel)

set_high_level(level, channel=None)[source]

Set high level (automated refill stop) setting on a given channel (None for the current channel)

BackendError

alias of pylablib.core.devio.comm_backend.DeviceBackendError

class NoParameterCaller(device, kind)

Bases: object

Class to simplify calling functions without a parameter

apply_settings(settings)

Apply the settings.

settings is a dict {name: value} of the available device settings. Non-applicable settings are ignored.

ask(msg, data_type='string', delay=0.0, timeout=None, read_echo=False)

Write a message and read a reply.

msg is the query message, delay is the delay between write and read. Other parameters are the same as in read(). If read_echo==True, assume that the device first echoes the input and skip it.

flush(one_line=False)

Flush the read buffer (read all the available data and return the number of bytes read).

If one_line==True, read only a single line.

static get_arg_type(arg)

Autodetect argument type

get_device_variable(key)

Get the value of a settings, status, or full info parameter

get_esr(timeout=None)

Get the device status register (by default, "*ESR?" command)

get_full_info(include=0)

Get dict {name: value} containing full device information (including status and settings).

include specifies either a list of variables (only these variables are returned), a priority threshold (only values with the priority equal or higher are returned), or "all" (all available variables). Since the lowest priority is -10, setting include=-10 queries all available variables, which is equivalent to include="all".

get_full_status(include=0)

Get dict {name: value} containing the device status (including settings).

include specifies either a list of variables (only these variables are returned), a priority threshold (only values with the priority equal or higher are returned), or "all" (all available variables). Since the lowest priority is -10, setting include=-10 queries all available variables, which is equivalent to include="all".

get_id(timeout=None)

Get the device IDN. (query SCPI '*IDN?' command)

get_settings(include=0)

Get dict {name: value} containing all the device settings.

include specifies either a list of variables (only these variables are returned), a priority threshold (only values with the priority equal or higher are returned), or "all" (all available variables). Since the lowest priority is -10, setting include=-10 queries all available variables, which is equivalent to include="all".

is_opened()

Check if the device is connected

lock(timeout=None)

Lock the access to the device from other threads/processes (isn’t necessarily implemented)

locking(timeout=None)

Context manager for lock & unlock

open()

Open the backend

static parse_array_data(data, fmt, include_header=False)

Parse the data returned by the device. fmt is DataFormat description in numpy format (e.g., "<u2").

If include_header==True, the data is assumed to be in a (somewhat) standard SCPI format: b'#', then a single digit s denoting length of the size block, then s digits denoting length of the data (in bytes) followed by the actual data. Otherwise (include_header==False), assume that the header is already removed.

read(data_type='string', timeout=None)

Read data from the device.

data_type determines the type of the data. Can be 'raw' (just raw data), 'string' (with trailing and leading spaces stripped), 'int', 'float', 'bool' (interprets 0 or 'off' as False, anything else as True), 'value' (returns tuple (value, unit), where value is float), a callable (return the result of this callable applied to the string value), a dictionary (return the stored value corresponding to the string value, or to the value converted into integer if the string value is not present), or a list of data types (the result is treated as a list of values with the given types separated by commas). timeout overrides the default value.

read_binary_array_data(include_header=False, timeout=None, flush_term=True)

Read a binary data in the from the device.

The data assumes the standard binary transfer header consisting of "#" symbol, then a single digit with the size of the length string, then the length string containing the length of the binary data (in bytes). If include_header==True, return the data with the header; otherwise, return only the content. If flush_term==True, flush the following line to skip terminator characters after the binary data, which are added by some devices. timeout overrides the default value.

reconnect(new_instrument=True, ignore_error=True)

Remake the connection.

If new_instrument==True, create a new backend instance. If ignore_error==True, ignore errors on closing.

reset()

Reset the device (by default, "*RST" command)

set_device_variable(key, value)

Set the value of a settings parameter

sleep(delay)

Wait for delay seconds

unlock()

Unlock the access to the device from other threads/processes (isn’t necessarily implemented)

using_write_buffer()

Context manager for using a write buffer.

While it’s active, all the consecutive write() operations are bundled together with ; delimiter. The actual write is performed at the read()/ask() operation or at the end of the block.

wait(wait_type='sync', timeout=None, wait_callback=None)

Pause execution until device overlapped commands are complete.

wait_type is either 'sync' (perform wait_sync()), 'dev' (perform wait_dev()) or 'none' (do nothing).

wait_dev()

Pause execution of the device commands until device overlapped commands (e.g., taking sweeps) are complete.

Note that the code execution is not paused.

wait_sync(timeout=None, wait_callback=None)

Pause execution of the script until device overlapped commands (e.g., taking sweeps) are complete.

timeout and wait_callback override default constructor parameters.

write(msg, arg=None, arg_type=None, unit=None, bool_selector=None, wait_sync=None, read_echo=False, read_echo_delay=0.0)

Send a command.

Parameters:
  • msg (str) – Text message.
  • arg – Optional argument to append in the end. If a list of arguments is supplied, the result is joined with ",".
  • arg_type (str) – Argument type. Can be 'raw' (in which case data is sent raw), 'string', 'int', 'float', 'bool', a format string (such as '{:.3f}') or a list of argument types (for an iterable argument); if format string is used and the argument is a list or a tuple, then it is expanded as a list of arguments (e.g., arg_type='{0};{1}' with arg=[1,2] will produce a string '1;2'); if a list of types is used, each element of arg is converted using the corresponding type, and the result is joined with ",".
  • unit (str) – If not None, use it as a unit to append after the value.
  • bool_selector (tuple) – A tuple (false_value, true_value) of two strings to represent bool argument; by default, use ._bool_selector attribute.
  • wait_sync – if True, append the sync command (specified as ._wait_sync_comm attribute, "*OPC?" by default) after the message and pause the execution command is complete; useful in long set operations, where the device might ignore later inputs until the current command is complete; if None, use the class default ._default_write_sync attribute (False by default).
  • read_echo (bool) – If True, read a single line after write.
  • read_echo_delay (float) – The delay between write and read if read_echo==True.

Module contents