hvl_ccb.dev.base¶
Module with base classes for devices.
- class Device(dev_config=None)[source]¶
Bases:
hvl_ccb.configuration.ConfigurationMixin
,abc.ABC
Base class for devices. Implement this class for a concrete device, such as measurement equipment or voltage sources.
Specifies the methods to implement for a device.
- exception DeviceExistingException[source]¶
Bases:
Exception
Exception to indicate that a device with that name already exists.
- exception DeviceFailuresException(failures: Dict[str, Exception], *args)[source]¶
Bases:
Exception
Exception to indicate that one or several devices failed.
- failures: Dict[str, Exception]¶
A dictionary of named devices failures (exceptions).
- class DeviceSequenceMixin(devices: Dict[str, hvl_ccb.dev.base.Device])[source]¶
Bases:
abc.ABC
Mixin that can be used on a device or other classes to provide facilities for handling multiple devices in a sequence.
- add_device(name: str, device: hvl_ccb.dev.base.Device) → None[source]¶
Add a new device to the device sequence.
- Parameters
name – is the name of the device.
device – is the instantiated Device object.
- Raises
- devices_failed_start: Dict[str, hvl_ccb.dev.base.Device]¶
Dictionary of named device instances from the sequence for which the most recent start() attempt failed.
Empty if stop() was called last; cf. devices_failed_stop.
- devices_failed_stop: Dict[str, hvl_ccb.dev.base.Device]¶
Dictionary of named device instances from the sequence for which the most recent stop() attempt failed.
Empty if start() was called last; cf. devices_failed_start.
- get_device(name: str) → hvl_ccb.dev.base.Device[source]¶
Get a device by name.
- Parameters
name – is the name of the device.
- Returns
the device object from this sequence.
- get_devices() → List[Tuple[str, hvl_ccb.dev.base.Device]][source]¶
Get list of name, device pairs according to current sequence.
- Returns
A list of tuples with name and device each.
- remove_device(name: str) → hvl_ccb.dev.base.Device[source]¶
Remove a device from this sequence and return the device object.
- Parameters
name – is the name of the device.
- Returns
device object or None if such device was not in the sequence.
- Raises
ValueError – when device with given name was not found
- start() → None[source]¶
Start all devices in this sequence in their added order.
- Raises
DeviceFailuresException – if one or several devices failed to start
- stop() → None[source]¶
Stop all devices in this sequence in their reverse order.
- Raises
DeviceFailuresException – if one or several devices failed to stop
- class EmptyConfig[source]¶
Bases:
object
Empty configuration dataclass that is the default configuration for a Device.
- clean_values()¶
Cleans and enforces configuration values. Does nothing by default, but may be overridden to add custom configuration value checks.
- force_value(fieldname, value)¶
Forces a value to a dataclass field despite the class being frozen.
NOTE: you can define post_force_value method with same signature as this method to do extra processing after value has been forced on fieldname.
- Parameters
fieldname – name of the field
value – value to assign
- is_configdataclass = True¶
- classmethod keys() → Sequence[str]¶
Returns a list of all configdataclass fields key-names.
- Returns
a list of strings containing all keys.
- classmethod optional_defaults() → Dict[str, object]¶
Returns a list of all configdataclass fields, that have a default value assigned and may be optionally specified on instantiation.
- Returns
a list of strings containing all optional keys.
- classmethod required_keys() → Sequence[str]¶
Returns a list of all configdataclass fields, that have no default value assigned and need to be specified on instantiation.
- Returns
a list of strings containing all required keys.
- class SingleCommDevice(com, dev_config=None)[source]¶
Bases:
hvl_ccb.dev.base.Device
,abc.ABC
Base class for devices with a single communication protocol.
- property com¶
Get the communication protocol of this device.
- Returns
an instance of CommunicationProtocol subtype
- abstract static default_com_cls() → Type[hvl_ccb.comm.base.CommunicationProtocol][source]¶
Get the class for the default communication protocol used with this device.
- Returns
the type of the standard communication protocol for this device