pcdsdevices.pv_positioner.OnePVMotor

class pcdsdevices.pv_positioner.OnePVMotor(prefix: str, *, name: str, skip_small_moves: bool = False, atol: float | None = None, **kwargs)

The simplest possible pv_positioner: a single PV.

You can use this when you want to control an EpicsSignal as if it was a positioner.

Parameters:

  • prefix (str) – The PV to control

  • name (str, keyword-only) – A name to refer to this positioner.

Ophyd Device Components

Attribute

Class

Suffix

Docs

Kind

Notes

done

InternalSignal

normal

Inherited from PVPositionerDone

setpoint

EpicsSignal

normal

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.

move(*args, **kwargs)

Move to a specified position, optionally waiting for motion to complete.

Parameters:

  • position – 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:
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.

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_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 = None
actuate_value = 1
atol = 0
configuration_attrs
connected
done_value = 1
egu

The engineering units (EGU) for a position

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
readback = None
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'})
timeout

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