pcdsdevices.device.InterfaceDevice

class pcdsdevices.device.InterfaceDevice(*args, **kwargs)

A device that can include pre-instantiated objects on init.

This may be useful for setting up multiple devices that need to re-use the same objects in different ways without needing to duplicate their constructor arguments.

These pre-instantiated objects can be included by adding them as InterfaceComponent attributes in the class definition like so:

from ophyd.signal import Signal
from pcdsdevices.device import (InterfaceDevice,
                                InterfaceComponent as ICpt)

class MyDevice(InterfaceDevice):
    my_component = ICpt(Signal)

my_signal = Signal(name='my_signal')
my_device = MyDevice(
    'PREFIX', name='my_device',
    my_component=my_signal
    )

You can automatically turn a standard Device into an InterfaceDevice using the to_interface function.

Methods

configure(d: Dict[str, Any]) → Tuple[Dict[str, Any], Dict[str, Any]]

Configure the device for something during a run

This default implementation allows the user to change any of the configuration_attrs. Subclasses might override this to perform additional input validation, cleanup, etc.

Parameters:

d (dict) – The configuration dictionary. To specify the order that the changes should be made, use an OrderedDict.

Returns:

(old, new) tuple of dictionaries
Where old and new are pre- and post-configure configuration states.

describe() → OrderedDictType[str, Dict[str, Any]]

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)

Get the value of all components in the device

Keyword arguments are passed onto each signal.get(). Components beginning with an underscore will not be included.

read() → OrderedDictType[str, Dict[str, Any]]

Read data from the device.

This method is expected to be as instantaneous as possible, with any substantial acquisition time taken care of in trigger().

The OrderedDict returned by this method must have identical keys (in the same order) as the OrderedDict returned by describe().

By convention, the first key in the return is the ‘primary’ key and maybe used by heuristics in bluesky.

The values in the ordered dictionary must be dict (-likes) with the keys {'value', 'timestamp'}. The 'value' may have any type, the timestamp must be a float UNIX epoch timestamp in UTC.

Returns:: data (OrderedDict) – The keys must be strings and the values must be dict-like with the keys {'value', 'timestamp'}

read_configuration() → OrderedDictType[str, Dict[str, Any]]

Dictionary mapping names to value dicts with keys: value, timestamp

To control which fields are included, change the Component kinds on the device, or modify the configuration_attrs list.

stop(*, success=False): Stop the Device and all (instantiated) subdevices

summary()

trigger() → StatusBase

Trigger the device and return status object.

This method is responsible for implementing ‘trigger’ or ‘acquire’ functionality of this device.

If there is an appreciable time between triggering the device and it being able to be read (via the read() method) then this method is also responsible for arranging that the StatusBase object returned by this method is notified when the device is ready to be read.

If there is no delay between triggering and being readable, then this method must return a StatusBase object which is already completed.

Returns:: status (StatusBase) – StatusBase object which will be marked as complete when the device is ready to be read.

Attributes

configuration_attrs

connected

hints

kind

subscriptions: ClassVar[FrozenSet[str]] = frozenset({'acq_done'})