pcdsdevices.attenuator.AttBase

class pcdsdevices.attenuator.AttBase(prefix, *, name, **kwargs)

Base class for pre-L2SI beam power attenuators.

This is a device that puts an array of filters in or out to achieve a desired transmission ratio.

This class does not include filters, because the number of filters can vary. You should not instantiate this class directly, but instead use the Attenuator() factory function.

Ophyd Device Components

Attribute	Class	Suffix	Docs	Kind	Notes
setpoint	EpicsSignal	:COM:R_DES		normal
readback	EpicsSignalRO	:COM:R_CUR		hinted
actuate	EpicsSignal	:COM:GO		omitted
done	EpicsSignalRO	:COM:STATUS		omitted
energy	EpicsSignalRO	:COM:T_CALC.VALE		normal
trans_ceil	EpicsSignalRO	:COM:R_CEIL		omitted
trans_floor	EpicsSignalRO	:COM:R_FLOOR		omitted
user_energy	EpicsSignal	:COM:EDES		omitted
eget_cmd	EpicsSignal	:COM:EACT.SCAN		omitted
calcpend	EpicsSignalRO	:COM:CALCP		omitted

Methods

camonitor()

Shows a live-updating motor position in the terminal.

This will be the value that is returned by the position attribute.

This method ends cleanly at a ctrl+c or after a call to end_monitor_thread(), which may be useful when this is called in a background thread.

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.

end_monitor_thread()

Stop a camonitor() or wm_update() that is running in another thread.

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.

insert(wait=False, timeout=None, moved_cb=None)

Block the beam by setting transmission to zero.

move(*args, **kwargs)

Move to a specified position, optionally waiting for motion to complete. Unlike the standard move, this will fail with a clear error message when a move is already in progress.

Parameters:

• position (float) – Position to move to

• moved_cb (callable) – Call this callback when movement has finished. This callback must accept one keyword argument: ‘obj’ which will be set to this positioner instance.

• timeout (float, optional) – Maximum time to wait for the motion. If None, the default timeout for this positioner is used.

Returns:

status (MoveStatus)

Raises:

• TimeoutError – When motion takes longer than timeout

• ValueError – On invalid positions

• RuntimeError – If motion fails other than timing out, including when a move is attempted while another move is already in progress.

mv(position, timeout=None, wait=False, log=True)

Absolute move to a position.

Parameters:

• position – Desired end position.

• timeout (float, optional) – If provided, the mover will throw an error if motion takes longer than timeout to complete. If omitted, the mover’s default timeout will be use.

• wait (bool, optional) – If True, wait for motion completion before returning. Defaults to False.

• log (bool, optional) – If True, logs the move at INFO level.

mv_ginput(timeout=None)

Moves to a location the user clicks on.

If there are existing plots, this will be the position on the most recently active plot. If there are no existing plots, an empty plot will be created with the motor’s limits as the range.

mvr(delta, timeout=None, wait=False, log=True)

Relative move from this position.

Parameters:

• delta (float) – Desired change in position.

• timeout (float, optional) – If provided, the mover will throw an error if motion takes longer than timeout to complete. If omitted, the mover’s default timeout will be use.

• wait (bool, optional) – If True, wait for motion completion before returning. Defaults to False.

• log (bool, optional) – If True, logs the move at INFO level.

post_elog_status()

Post device status to the primary elog, if possible.

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.

remove(wait=False, timeout=None, moved_cb=None)

Bring the attenuator fully out of the beam.

screen()

Open a screen for controlling the device.

Default behavior is the typhos screen, but this method can be overridden for more specialized screens.

set(new_position: Any, *, timeout: float | None = None, moved_cb: Callable | None = None, wait: bool = False) → StatusBase

Set a value and return a Status object

Parameters:

• new_position (object) – The input here is whatever the device requires (this should be over-ridden by the implementation. For example a motor would take a float, a shutter the strings {‘Open’, ‘Close’}, and a goineometer (h, k, l) tuples

• timeout (float, optional) – Maximum time to wait for the motion. If None, the default timeout for this positioner is used.

• moved_cb (callable, optional) –

  Deprecated

  Call this callback when movement has finished. This callback must accept one keyword argument: ‘obj’ which will be set to this positioner instance.

• wait (bool, optional) –

  Deprecated

  If the method should block until the Status object reports it is done.

  Defaults to False

Returns:

status (StatusBase) – Status object to indicate when the motion / set is done.

set_energy(energy=None)

Sets the energy to use for transmission calculations.

Parameters:

energy (number, optional) – If provided, this is the energy we’ll use for the transmission calcluations. If omitted, we’ll clear any set energy and use the current beam energy instead.

set_position(position)

Alias for set_current_position.

Will fail if the motor does not have set_current_position.

status() → str

Returns a str with the current pv values for the device.

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.

tweak(scale=0.1)

Control this motor using the arrow keys.

Use left arrow to step negative and right arrow to step positive. Use up arrow to increase step size and down arrow to decrease step size. Press q or ctrl+c to quit.

Parameters:

scale (float) – starting step size, default = 0.1

umv(position, timeout=None, log=True, newline=True)

Move to a position, wait, and update with a progress bar.

Parameters:

• position (float) – Desired end position.

• timeout (float, optional) – If provided, the mover will throw an error if motion takes longer than timeout to complete. If omitted, the mover’s default timeout will be use.

• log (bool, optional) – If True, logs the move at INFO level.

• newline (bool, optional) – If True, inserts a newline after the updates.

umvr(delta, timeout=None, log=True, newline=True)

Relative move from this position, wait, and update with a progress bar.

Parameters:

• delta (float) – Desired change in position.

• timeout (float, optional) – If provided, the mover will throw an error if motion takes longer than timeout to complete. If omitted, the mover’s default timeout will be use.

• log (bool, optional) – If True, logs the move at INFO level.

• newline (bool, optional) – If True, inserts a newline after the updates.

wait(timeout=None)

wm()

Get the mover’s current positon (where motor).

wm_update()

Shows a live-updating motor position in the terminal.

This will be the value that is returned by the position attribute.

This method ends cleanly at a ctrl+c or after a call to end_monitor_thread(), which may be useful when this is called in a background thread.

Attributes

actuate_value

Sets the value we use in the ‘GO’ command.

This command will return 3 if the setpoint is closer to the ceiling than the floor, or 2 otherwise. In the unlikely event of a tie, we choose the floor.

This will wait until a pending calculation completes before returning.

configuration_attrs

connected

done_value = 0

egu = ''

high_limit

hints

kind

limits

low_limit

moving

Whether or not the motor is moving

If a done PV is specified, it will be read directly to get the motion status. If not, it determined from the internal state of PVPositioner.

Returns:

bool

position

The current position of the motor in its engineering units

Returns:

position (any)

put_complete

settle_time

Amount of time to wait after moves to report status completion

stop_signal = None

stop_value = 1

subscriptions: ClassVar[FrozenSet[str]] = frozenset({'_req_done', 'acq_done', 'done_moving', 'readback', 'start_moving', 'state'})

timeout

Amount of time to wait before to considering a motion as failed

transmission

Ratio of pass-through beam to incoming beam as a value between 1 (full beam) and 0 (no beam).