Experimental Physics and
Industrial Control System

Andrew Johnson <[email protected]> · Tue, 12 Jun 2018 10:11:09 -0500

Hi,

On 06/11/2018 02:49 AM, Abdalla  Ahmad wrote:
> Is there anything in EPICS database that allows me to write a PV value
> to tens of PVs? More than what fanout and dfanout can do? For example we
> have a dummy PV that holds a current value to be written to 32 power
> supplies and I am using a sequencer to achieve this.

If you really need to do a put, I would suggest giving each power supply
its own output record (ao) with the DOL field configured as a CA link
with the CP flag set, pointing to the PV holding the value to be used,
and its OUT field pointing to wherever you want the put to go. The CP
flag causes all the output records to be processed whenever a new
monitor update is posted from that record. That record should have its
MDEL field set to -1 if you want the outputs to always process whenever
a new value is generated even if it's the same as it was before; if you
leave MDEL at the default of zero then the output records will not
process when there is no change to the value.

record(ai, "$(P):current") {
    field(MDEL, -1)	# If required
}

# Repeat for each PSU n=0..31
record(ao, "$(P):PS$(n):put") {
    field(DOL, "$(P):current CP")
    field(OMSL, "closed_loop")
    field(OUT, "$(P):PS$(n):current")
}

You can use the SDIS link in the output records to enable/disable this
behaviour as required.

HTH,

- Andrew

-- 
Arguing for surveillance because you have nothing to hide is no
different than making the claim, "I don't care about freedom of
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Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System