Experimental Physics and
Industrial Control System

I am working on writing a new IOC for QuadEM device, and the IOC mostly works.  The IOC talks over TCP via asyn to a middle software layer that talks to the hardware.  The middle layer can send unsolicited messages to EPICS, so I implemented polling by having a record scan once a second and read the port.  Sometimes, however, I get a case where EPICS seems to be queueing writes, so I would get

Change parameter A -> No message send

Change parameter B -> Send A

Change parameter C -> Send B

 

All writes, which includes the 1 Hz record mentioned above, write to the same shared buffer that is then sent, so might there be contention there?

 

Thank you,

 

Iain Marcuson

Software Engineer, Sydor Technologies

585.278.1168 | www.SydorTechnologies.com

Skype: iain.marcuson at sydorinstruments.com