Experimental Physics and
Industrial Control System

"Jeff Hill" <[email protected]> · Tue, 3 Jul 2007 09:25:11 -0600

Hello Heinrich,

The maximum array size transferable is limited by the
EPICS_CA_MAX_ARRAY_BYTES configuration for both the client (in this case
MEDM) and the server (in this case the IOC). More precisely, the maximum
array transferable is the minimum of the two EPICS_CA_MAX_ARRAY_BYTES
configurations set for the client and the server. You will receive some
warning messages if the array sent by the server can't be received by the
client, or visa-versa.

Jeff Hill

-----Original Message-----
From: [email protected] [mailto:[email protected]]
On Behalf Of Heinrich du Toit
Sent: Tuesday, July 03, 2007 7:37 AM
To: TechTalk EPICS
Subject: tds3000

Hi

I've compiled the tds3000 library. And connected it to a tds5000 scope.
Works great.

Just something that bothers me.
It seem like the thing need to work with 100000 values in the array.
Now firstly this seems to make anything more than .5 refresh rate
impossible. Why is this? It's not like you can really plot 100K points?
1K would be more than enough.

Plus if I put the MEDM screen in single display mode the whole thing
would blink/flash a few times when it refreshes.
I have accelerated nvidia - ubuntu setup so it's not the pc that's 2
slow. It seem the thing redraws the screen about 20+ times everytime.
Once again not needed I think. ?

Most of all this is irritating and I can't go and put up a flashing
scope display in the control room :) 

I tried changing the 
epicsEnvSet(EPICS_CA_MAX_ARRAY_BYTES, 100000)
line in st.cmd
But this seems to break the system completely :( Guess it's hard coded
somewhere.

If this can't be modified that's ok.
I can work with multi-display and keep update rate 1 sec or slower.
Was just wondering.

Thanks
-Heinrich

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System