Experimental Physics and
Industrial Control System

Hi Torsten,

Ø  The PLC gives us some names for enmums, resulting in a call to

Ø  pC_->doCallbacksEnum()

doCallbacksEnum() is only intended to be called when an enum value changes at run-time, i.e. after iocInit.  For enums that the driver determines at initialization you should simply implement the asynPortDriver::readEnum() method.  Device support will call your driver during iocInit to read the enum values/strings/severities for all records with enum VAL fields.

testAsynPortDriver has an example here:

https://github.com/epics-modules/asyn/blob/a94a78987a99b1c36bbd641a67341069dc5d627e/testAsynPortDriverApp/src/testAsynPortDriver.cpp#L340

It also has an example of using doCallbacksEnum(), which it does when the vertical gain is changed at run time.

https://github.com/epics-modules/asyn/blob/a94a78987a99b1c36bbd641a67341069dc5d627e/testAsynPortDriverApp/src/testAsynPortDriver.cpp#L374

Mark

Hi Torsten,

I assume this an Asyn port driver; what is triggering the I/O that results in your code doing that callback? The callback shouldn't happen until after the EPICS global interruptAccept is non-zero, any earlier than that and the IOC and records won't be ready for device support to call it. The asynPortDriver code looks like it ignores all such calls before then. If the code needs something to trigger that processing it could register an initHook and wait for the value initHookAfterInterruptAccept, which is only sent once (i.e. it doesn't get repeated if the IOC is paused), or for initHookAfterDatabaseRunning which is repeated after an IOC pause is rescinded.

HTH,

- Andrew

Hej experts,

I have an IOC that talks to a PLC-ish system.

The PLC gives us some names for enmums, resulting in a call to

pC_->doCallbacksEnum()

However,  most often the response from the PLC comes back

to the IOC before the record has registered for the callback.

And the enums in the mbbi record are not updated.

Delaying the polling does work around this problem -

but is there a better solution ?