Instrument#

class Instrument(

name: str,

publishers: list[Publisher] | None = None,

background_config: BackgroundDaemonConfig | None = None,

legacy_naming: bool = False,

**kwargs,

)[source]#

Base class for Nominal instrument interfaces. Owns publishing and the background daemon.

Initialize an Instrument.

Parameters:

name – Channel-name prefix for published data.
publishers – Publishers that receive emitted Measurement/Command data.
background_config – Background-daemon settings; default if omitted.
legacy_naming – When True, publish channels under their pre-v1.0 names (e.g. main.ch1_v instead of main.ch1.voltage for PSU) for dashboards or recorded datasets keyed on those names. The setting is all-or-nothing per instrument. PSU, ELoad, I2C, InstroScope, and DAQ digital channels honor the flag; the categories with no v1.0 rename (DMM, Modbus, DAQ analog and relay channels) ignore it. Scheduled for removal in v2.0.
**kwargs – Default tags applied to every emitted Measurement or Command. Pass dataset_rid="<rid>" to auto-create a NominalCorePublisher (uses the on-disk ‘default’ Nominal credential).

Attributes

`background_interval`	Seconds between background daemon iterations (0 = no wait).
`channel_names`	Return an insertion-ordered snapshot of all published channel names.

Methods

`add_background_daemon_function`	Append `method` to the daemon's call list.
`add_publisher`	Register a publisher to receive this instrument's Measurement/Command data.
`close`	Stop the background daemon and close every publisher.
`define_background_daemon`	Replace all daemon functions with a single `method` (called with the given args).
`get_channel`	Return the most recent `length` samples for `channel_name` from the in-memory buffer.
`get_single_channel_value`	Return the most recent sample for `channel_name` from the in-memory buffer.
`open`	No-op base hook.
`publish`	Fan `data` out to every configured publisher; `kwargs` pass through.
`start`	Start the background daemon thread.
`stop`	Signal the background daemon to stop and join it.
`_package_command`	Build a single-channel `Command` namespaced under this instrument.
`_package_measurement`	Build a single-channel `Measurement` namespaced under this instrument.