qmi.core.instrument

Implementation of the QMI_Instrument class.

Classes

QMI_Instrument(context, name)	Base class for all instrument drivers.
QMI_InstrumentIdentification(vendor, model, ...)

class qmi.core.instrument.QMI_InstrumentIdentification(vendor, model, serial, version)

count(value, /)

Return number of occurrences of value.

index(value, start=0, stop=9223372036854775807, /)

Return first index of value.

Raises ValueError if the value is not present.

model: str | None

Alias for field number 1

serial: str | None

Alias for field number 2

vendor: str | None

Alias for field number 0

version: str | None

Alias for field number 3

class qmi.core.instrument.QMI_Instrument(context: qmi.core.context.QMI_Context, name: str)

Base class for all instrument drivers.

After an instance of QMI_Instrument is created, it must be explicitly opened by calling the open() method before any interaction with the instrument is possible.

Subclasses implement drivers for specific instrument types.

All drivers must implement methods open() and close() which initializes resp. tears down the connection to the instrument hardware.

Subclasses should add methods to implement instrument-specific operations (measurements, getting and setting of parameters).

Driver should implement a method reset() when applicable. This method returns the instrument to its default settings.

Drivers should implement a method get_idn() when applicable. This method returns an instance of QMI_InstrumentIdentification.

classmethod get_category() → str | None

Return the optional name of the category this object belongs to.

A category name is a free-form string that has no special significance. Its purpose is to distinguish between groups of RPC objects that fulfill similar roles.

release_rpc_object() → None

Give a warning if the instrument is removed while still open.

is_open() → bool

Return True if the instrument is open (ready for interaction).

open() → None

Connect to the instrument hardware.

When this method returns, the instrument must be ready for interaction via calls to instrument-specific methods.

Subclasses can extend this method to implement instrument-specific initialization. If they do, they should call super().open() as a last statement.

close() → None

Close the connection to the instrument hardware and release associated resources.

When this method returns, the instrument must not be used again unless it is first re-opened by calling the open() method.

Subclasses can extend this method if they have specific resources to close. If they do, they should call super().close() as a last statement.

force_unlock() → None

Forcefully unlock the remote object.

This unlocks the object, regardless of who owns the lock. This allows you to unlock an object if the locking proxy has been destroyed without unlocking.

Use this with care.

Do not override this stub method in subclasses. It has already been implemented in QMI_RpcProxy.

get_name() → str

Return the name of this object.

Returns:

name attribute.

get_signals() → list[SignalDescription]

Return a list of signals that can be published by this object.

Returns:

List consisting of qmi_signals attributes.

is_locked() → bool

Query if the remote object is locked.

Do not override this stub method in subclasses. It has already been implemented in QMI_RpcProxy.

lock(timeout: float = 0.0, lock_token: str | None = None) → bool

Lock the remote object. If timeout is given, try every 0.1s within the given timeout value. The remote object can be locked with an optional custom lock token by giving a string into lock_token keyword argument.

If successful, this proxy is the only proxy that can invoke RPC methods on the remote object; other proxies will receive an “object is locked” response. The return value indicates if the lock was granted; a denied lock means the object was already locked by another proxy.

Do not override this stub method in subclasses. It has already been implemented in QMI_RpcProxy.

unlock(lock_token: str | None = None) → bool

Unlock the remote object.

Without optional parameters, this is only allowed by the proxy that initially locked the object. By giving the lock token as an input parameter, the specific object locked by this token can be unlocked. The return value indicates if the unlocking was successful.

Do not override this stub method in subclasses. It has already been implemented in QMI_RpcProxy.