pcdsdevices.signal.PVStateSignal

class pcdsdevices.signal.PVStateSignal(*, name, **kwargs)

Signal that implements the PVStatePositioner state logic.

See AggregateSignal for more information.

Methods

describe()

Provide schema and meta-data for read()

This keys in the OrderedDict this method returns must match the keys in the OrderedDict return by read().

This provides schema related information, (ex shape, dtype), the source (ex PV name), and if available, units, limits, precision etc.

Returns: data_keys (OrderedDict) – The keys must be strings and the values must be dict-like with the event_model.event_descriptor.data_key schema.

get(**kwargs): Update all values and recalculate.

read()

Put the status of the signal into a simple dictionary format for data acquisition

Returns: dict

read_configuration(): Dictionary mapping names to value dicts with keys: value, timestamp

set(value, *, timeout=None, settle_time=None)

Set is like put, but is here for bluesky compatibility

Returns: st (Status) – This status object will be finished upon return in the case of basic soft Signals

trigger(): Call that is used by bluesky prior to read()

Attributes

SUB_META = 'meta'

connected: Is the signal connected to its associated hardware, and ready to use?

high_limit: The high, inclusive control limit for the Signal

hints: Field hints for plotting

kind

limits: The control limits (low, high), such that low <= value <= high

low_limit: The low, inclusive control limit for the Signal

metadata: A copy of the metadata dictionary associated with the signal

metadata_keys: Metadata keys that will be passed along on value subscriptions

read_access: Can the signal be read?

timestamp: Timestamp of the readback value

tolerance: The absolute tolerance associated with the value.

value: The signal’s value

write_access: Can the signal be written to?