pcdsdevices.slits.JJSlits

class pcdsdevices.slits.JJSlits(*args, nominal_aperture=5.0, **kwargs)

Beckhoff Controlled AT-C8-HV JJ X-Ray Slits. The JJSlits class defines motor components for the specific JJ X-Ray slits model AT-C8-HV. This model of JJSlits holds four in-vacuum motors that set the position and opening of the aperture in two dimensions. For each dimension, one motor defines the aperture opening, and another determines the position of the aperture. This class allows an operator to control and scan the position ‘center’ and opening ‘width’ of the aperture. The ‘JJSlits’ class instantiates four sub-devices: ‘JJSlits.xwidth’, ‘JJSlits.xcenter’, ‘JJSlits.ywidth’, ‘JJSlits.ycenter’. Beckhoff controlled JJSlits are implemented along the beamline in HXR for beam attenuation.

Parameters:

• prefix (str) – Base PV for the JJ X-RAY PLC System

• name (str, keyword-only)

Ophyd Device Components

Attribute	Class	Suffix	Docs	Kind	Notes
lightpath_summary	SummarySignal			omitted	Inherited from SlitsBase
nominal_aperture	Signal			normal	Inherited from SlitsBase
xwidth	BeckhoffAxis	:XWIDTH		normal	Inherited from SlitsBase
ywidth	BeckhoffAxis	:YWIDTH		normal	Inherited from SlitsBase
xcenter	BeckhoffAxis	:XCENTER		normal	Inherited from SlitsBase
ycenter	BeckhoffAxis	:YCENTER		normal	Inherited from SlitsBase

Methods

calc_lightpath_state(xwidth: float, ywidth: float) → LightpathState

Create and return a LightpathState object containing information needed for lightpath, given a set of signal values

kwargs should be the same as the signal names provided in lightpath_cpts

Device logic goes here.

Returns:

LightpathState – a dataclass containing the Lightpath state

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.

get_lightpath_state(use_cache: bool = True) → LightpathState

Return the current LightpathState

Returns:

LightpathState – a dataclass containing the Lightpath state

move(width, height=None, *, wait=False, moved_cb=None, timeout=None)

Set the dimensions of the width/height of the slits gap.

Parameters:

• size (float or tuple of float) – Target size for slits in both x and y axis. If a square gap is desired, a single value can be entered. Otherwise, the width and height can both be entered, either as separate arguments or as a tuple.

• wait (bool, optional) – If True, block until move is completed. Defaults to False.

• timeout (float, optional) – Maximum time for the motion. If None is given, the default value of xwidth and ywidth positioners is used.

• moved_cb (callable, optional) – Function to be run when the operation finishes. This callback should not expect any arguments or keywords.

Returns:

status (AndStatus) – Logical combination of the request to both horizontal and vertical motors.

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.

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(size=None, wait=False, timeout=None, **kwargs)

Open the slits to unblock the beam.

Parameters:

• size (float, optional) – Open the slits to a specific size. Defaults to .nominal_aperture.

• wait (bool, optional) – Wait for the status object to complete the move before returning.

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

Returns:

Status – ~ophyd.Status object based on move completion.

See also

Slits.move()

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(size)

Alias for the move method, here for bluesky compatibilty.

classmethod set_defaults(*, connection_timeout=10.0)

Set class-wide defaults for device communications

This may be called only before any instances of Device are made.

This setting applies to the class it is called on and all its subclasses. For example,

>>> Device.set_defaults(...)

will apply to any Device subclass.

Parameters:

connection_timeout (float, optional) – Time (seconds) allocated for establishing a connection with the IOC.

Raises:

RuntimeError – If called after EpicsSignalBase has been instantiated for the first time.

stage_group_instances() → Iterator[OphydObject]

Yields an iterator of subdevices that should be staged.

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.

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

configuration_attrs

connected

connection_timeout

current_aperture

Current size of the aperture. Returns a tuple in the form (width, height).

hints

kind

lightpath_cpts = ['xwidth.user_readback', 'ywidth.user_readback']

md

needs_parent: list[type[OphydObject]] = [<class 'ophyd.signal.AttributeSignal'>, <class 'ophyd.signal.DerivedSignal'>, <class 'ophyd.areadetector.plugins.PluginBase'>, <class 'ophyd.pseudopos.PseudoSingle'>, <class 'pcdsdevices.signal.PVStateSignal'>, <class 'pcdsdevices.signal.AggregateSignal'>]

position

stage_group: list[Component] = [Component(SignalRO, kind='normal'), Component(SignalRO, kind='normal')]

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