Experimental Physics and
Industrial Control System

"Szalata, Zenon M." <[email protected]> · Fri, 31 Oct 2008 11:45:56 -0700

Thanks Eric,
I think I can combine these two IOC's into one.  Once that is done, do I need to do anything special to coordinate orderly access to the two instruments or does asyn handle it for me? 

Thanks again,
Zen

-----Original Message-----
From: Eric Norum [mailto:[email protected]] 
Sent: Friday, October 31, 2008 10:03 AM
To: Szalata, Zenon M.
Cc: EPICS Techtalk
Subject: Re: GPIB - asyn - streamdevice

Would it be possible to run both instruments from the same soft IOC?
I don't think that it would be easy to try and mutex the requests from separate clients of the GPIB/LAN adapter.

On Oct 31, 2008, at 11:05 AM, Szalata, Zenon M. wrote:

> I have two GPIB instruments attached to ICS 8065 Ethernet - GPIB 
> Controller (according to the manual this device is a replacement for 
> the Agilent E2050 and E5810).  I have written two soft IOC's to 
> control and monitor two instruments (one is Agilent 33220A Waveform 
> Generator, the other is Boonton 4500B RF Peak Power Analyzer).  Both
> IOC programs use epics R3-14-9, asyn R4-9, and streamdevice R2-3.   
> The 33220A IOC has a records with SCAN="1 second", which reads the 
> status byte.  The 4500B IOC has a waveform record with SCAN="5 
> second", which is used to read waveform data, a stream of ASCII coded 
> floating point values.  The waveform consists of 500 data points.  
> This stream of data is converted to floating point data in a genSub 
> record.
>
> The 4500B IOC program performs flawlessly when it is the only one 
> running.  When the 33220A IOC program is also running, the waveform 
> data read by the 4500B IOC gets corrupted from time to time.  I 
> interpret what is happening as follows: while the waveform data is 
> being read, the other IOC program requests a status byte and somehow 
> these two concurrent operations interfere with each other.  How can I 
> solve this?  Is it possible to make reading the waveform an atomic 
> operation (i.e. uninterruptable)?
>
> I am using the following streamdevice protocol for reading the
> waveform:
> rTDCh12{ InTerminator="";  out "TRAC:SOUR CH\$1;:TRAC\$1:INDEX 
> 1;:TRAC\$1:AVER:DATA?"; in "%10000c";}
>
> Any suggestions will be greatly appreciated.
>
> Zen
>

--
Eric Norum <[email protected]>
Advanced Photon Source
Argonne National Laboratory
(630) 252-4793

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System