Hi all,
I have three devices connected to a compact fieldpoint 2020 via RS232 using
the VISA drivers. Th programm runs smoothly as long as I use only 1 or 2 of
these devices. If I try to use all of them, it runs only for a certain time and then
one loop hangs forever. This loop contains controls for two bath cryostats by
Lauda, the communication is done using their labview drivers which are "normal"
vi's unsing VISA internally. Whlie debugging I found that the hang is caused
by the VISA-write command. There seems to be no timeout active to prohbit
a hang of this call forever. Is there a workaurond for this or a way I could
debug and fix this problem? Unfortunately, it only happens after a while so there
seem to be special conditions on the fieldpoint neccesary to cause this hang.
The only additional information I can provide is the fact, that this "seems" to
happen always on COM3 (I haven't tried to switch ports and devices yet to
test if it is the device or the port) while the device on COM1 (a multi channel
analyser) is transmitting a lot of data. This is done in a second RT-timed
loop which is running without a problem while the other RT-loop is hanging.
Thanks for your help,
Olaf
Labview: 7.1 with latest VISA drivers (I hope, those that came with 7.1)
and RT-modules.
Lauda drivers (LD1002) for the proline cryostats were taken from here:
http://www.lauda.de/hosting/lauda/website_de.nsf/urlnames/BMJL-5XNCMN/$file/LD1002.exe
Message Edited by Olaf Stetzer on 02-16-2006 03:00 AM
