Instruments

Measurement configurations utilize ExperimentParameters, which are a way of describing dictionary structures using CSV files defined in the rminstr package.

All the configurations for every instrument, along with any other settings, are provided as a list of files to the measurement runner. These are concatenated into a single large dictionary that is used by the runner to run the measurement. These files include things like:

• What instruments need to be connected to?

• What are the instruments settings at different points in the measurement?

• What is the important metadata about the measurement?

• What are the instruments doing (i.e what is their role) in the measurement?

The required fields for a given measurement are defined using JSON schema, which are given in the configuration reference.

They follow the general structure of

• A set of general configurations corresponding to the overarching measurement.

  • Data column, required metadata, etc.

• A set of instrument configurations that specify every controlled instrument in the measurement.

  • Models, serials, roles, etc.

Instruments can have a type and a role. For example, a Voltmeter is a type of instrument, but doesn’t describe what it’s doing in the measurement. The role describes what it’s doing, which could be a thermopile_monitor or a bias_monitor.

The type of instrument is directly related to the measurement functionality interfaces defined in rminstr . Settings a given instrument can utilize are directly defined by the settings available for different measurement interfaces defined by that package.

Every instrument needs an initial_settings field to define what the instrument should be initialized too. Measurement runners may require additional operational mode fields to define what the instrument settings should be for different modes in the measurement. For example, an RF sweep has a monitor_mode during its initial warm up at every frequency point while the thermopile comes to equilibrium and a fast_off mode that occurs at the end of every frequency point.

For example, the HP HP3458A could be used to as a thermopile_monitor to monitor the voltage of a thermoelectric, or as a bias_monitor to monitor the voltage of a Type IV power meter. Below is an example of an instrument configuration that configures the an HP 3458A to operate as a bias_monitor.

HP3458A BiasMonitor

key_0	key_1	key_2	key_3	value	type	comment
instruments	DVM1	model		HP3458A	str	make and model of instrument; used to determine which commands to use
instruments	DVM1	serial		1186	str	last 4 digits of serial number
instruments	DVM1	GPIB_address		GPIB0::22::INSTR	str	GPIB address
instruments	DVM1	role		bias_monitor	str	an instrument’s role is its specific use in the context of this measurement
instruments	DVM1	output_column		DVM_volts	str	For the bias monitor the output column is DVM_volts
instruments	DVM1	initial_settings	v_range	10	float	settings for this instrument in monitor mode
instruments	DVM1	monitor_mode_settings	nplc	100	float	settings for this instrument in monitor mode
instruments	DVM1	monitor_mode_settings	num_readings	1	int	settings for this instrument in monitor mode
instruments	DVM1	monitor_mode_settings	timer	0	float	settings for this instrument in monitor mode
instruments	DVM1	monitor_mode_settings	timeout	5	float	timeout for wait_until_data_available (seconds)
instruments	DVM1	fast_off_mode_settings	nplc	1	float	the state of the instrument for fast_off measurements
instruments	DVM1	fast_off_mode_settings	num_readings	300	int	the state of the instrument for fast_off measurements
instruments	DVM1	fast_off_mode_settings	timer	0.05	float	the state of the instrument for fast_off measurements
instruments	DVM1	fast_off_mode_settings	timeout	100	float	timeout for wait_until_data_available (seconds)