Re: Process aSub record on arrival of data

[Andrew Johnson via Tech-talk <tech-talk at aps.anl.gov>]

Hi Matt,

On 7/27/23 1:33 PM, Matt Rippa via Tech-talk wrote:

I have 2 aSub records: Tx on IOC  A and Rx on IOC B.

IOC A and B are on different machines on my network.

I want Tx to send an array to Rx over CA (or PVA). Once the data arrives is there a stock method to trigger Rx to process? IIUC, using the CPP attribute in Tx.OUTA will not cause the Rx to process since these records are on different IOC's. I'm using another OUT link in Tx to write to Rx.PROC.

Is that the most efficient way to do this?

The standard and most efficient way would be to have RX.INPA be a CA link to the TX.VALA field with the CPP link flag set, then every time TX updates its VALA field the CA monitor event will update the RX.A array and process that record immediately. If you want to make that processing conditional there are a couple of different ways to do that, but that's a different question for a different email.

HTH,

- Andrew

I know there's history to this and the genSub record at Gemini has been customized to process on the arrival of data to certain input fields. I'm trying to accomplish that in an aSub.

Example below

EPICS 7 latest build from github.

Linux Rocky 8

Thanks!

-Matt

===========IOC A==============

 record(aSub,"test:TX") {
       field(SNAM,"transmitter")
       field(NOVA, "5")
       field(OUTA, "test:RX.A NPP NMS")
       field(OUTB, "test:RX.PROC NPP NMS")
   }

===========IOC B==============

record(aSub,"test:RX") {
      field(NOA, "5")
}

-- 
Complexity is free, it's Simplicity that takes work.