Re: GPIB - asyn - streamdevice

[Eric Norum <norume@aps.anl.gov>]

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 <norume@aps.anl.gov>
Advanced Photon Source
Argonne National Laboratory
(630) 252-4793