Experimental Physics and
Industrial Control System

Dirk Zimoch <[email protected]> · Mon, 26 Aug 2013 17:25:59 +0200

On 26.08.2013 16:22, Michael Davidsaver wrote:

One mechanism for accomplishing what you ask is a delayed callback based
on a timer. When coupled with asynchronous records (what the asyn module
is based on) this gives a way to have long delays in record processing
without locking everything up.

That's actually what StreamDevice is doing when it finds a 'wait'

command in the protocol.

See http://epics.web.psi.ch/software/streamdevice

Dirk

For an example see

https://pubweb.bnl.gov/~mdavidsaver/epics-doc/epics-devsup.html#_asynchronous_example

Michael

On 08/26/2013 04:18 AM, Vikram Bhagat wrote:

Dear all,
I want to know how to create and handle EPICS thread at run time.
In my application, i am using serial communication. I am
reading/writing data from serial port.
I am using Asyn driver.

In my application i have added one more functionality (asyn reason) to
wait for user-define time and then complete record processing.
In this function caput <PV name> with time in seconds will wait for
that much seconds (I put one loop to read system time and check that
user-defined time has been reached or not) and then "return asynSuccess".

This is working fine but problem now is-> the system is not processing
any other record/PV till the delay time will complete. Means if i user
requested delay time for 5 minutes--> the system will not process
other reading or writing PV till 5 minutes complete.

How i can handle this situation? while system is waiting for time
delay other record needs to be processed and have to give values or
write to the output.

I think i have to create epicsThread for this delay. so it will run in
separate thread and other functions can work independently. But in my
case after completion of my delay i have to delete Thread ... How i
can delete that Thread and make sure that my asyn driver will return
asynSuccess for that delay function?

Thanks & regards
Vikram

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System