QCSDataEngineCA Class
Connect to EPICS process variables (PV) via Channel Access (CA). More...
| Header: | #include <QCSDataEngineCA> |
| Inherits: | QCSDataEngine |
Public Functions
| QCSDataEngineCA(QObject *parent = Q_NULLPTR) | |
| virtual | ~QCSDataEngineCA() |
Reimplemented Public Functions
| virtual ObjectModel * | allData() |
| virtual void | close(QCSData *data) |
| virtual void | create(QCSData *data) |
| virtual QString | description() |
| virtual QString | name() |
| virtual void | setValue(QCSData *data, const QVariant value) |
- 6 public functions inherited from QCSDataEngine
- 32 public functions inherited from QObject
Additional Inherited Members
- 3 properties inherited from QCSDataEngine
- 1 property inherited from QObject
- 1 public slot inherited from QObject
- 1 signal inherited from QCSDataEngine
- 2 signals inherited from QObject
- 1 public variable inherited from QObject
- 10 static public members inherited from QObject
- 9 protected functions inherited from QObject
- 2 protected variables inherited from QObject
Detailed Description
Connect to EPICS process variables (PV) via Channel Access (CA).
This data engine source has a ca:// scheme, followed by the PV name. And since this is the default data engine, the ca:// scheme can be omitted.
If the PV value is of array type, the data type might be up casted to either int or double. This is because the qml engine transparent handles QVector<int> and QVector<double> Sequence Type to JavaScript Array. To always return the native data type, set the extraProperties:
QCSData data = new QCSData(); data->setExtraProperty("UseNativeType", true); data->setSource("my_array_pv");
Note: it creates a preemptive channel access context, but anyway has a 100ms timer to flush the io to improve the IO efficiency.
Member Function Documentation
QCSDataEngineCA::QCSDataEngineCA(QObject *parent = Q_NULLPTR)
Default constructs an instance of QCSDataEngineCA.
[virtual] QCSDataEngineCA::~QCSDataEngineCA()
Destroys the instance of QCSDataEngineCA. The destructor is virtual.
[virtual] ObjectModel *QCSDataEngineCA::allData()
Reimplemented from QCSDataEngine::allData().
[virtual] void QCSDataEngineCA::close(QCSData *data)
Reimplemented from QCSDataEngine::close().
[virtual] void QCSDataEngineCA::create(QCSData *data)
Reimplemented from QCSDataEngine::create().
Creates the EPICS channel.
It calls ca_create_channel with a connection callback. In the callback, it calls ca_create_subscription to monitor value, alarm and property changes.
[virtual] QString QCSDataEngineCA::description()
Reimplemented from QCSDataEngine::description().
[virtual] QString QCSDataEngineCA::name()
Reimplemented from QCSDataEngine::name().
Returns the source scheme ca.
[virtual] void QCSDataEngineCA::setValue(QCSData *data, const QVariant value)
Reimplemented from QCSDataEngine::setValue().