I am trying to re-create a behavior I can get using HTBasic with an
instrument that apparently is quite sensitive to GPIB commands.
I simply want to read the measurement value presented by the instrument, but
I can't get it to work with standard ibdev, ibwrt, ibrd commands. So, I have
tried HTBasic which can make it work and used the NI GPIB-Spy to sniff out
what is going on and now I hope for some help to recreate this behavior in
LabWindows or LabView. I am using an AT-GPIB/TNT card under WIndows 95.
The following sequence is what goes on when HTBasic initialises (LOAD BIN
"GPIBNI+"):
ibfind GPIB0
ibonl 1
ibpad 21
ibtmo T1s
ibeot 0
ibsic
ibsre 1
ibgts 0
ibpad 21
Now each time I as to read a value from the inst
rument on adress 8 (using
ENTER 708;S$) the following happens
ibcmd "H?5"
ibrd 1
ibrd 1
.... until ibsta includes (end)
As far as I can deciffer this, the program is setting the controller up
directly and Talks/Listens directly on the adress it assigned itself (21)
and the instrument adress (8). If I do all this step by step in IBIC it also
works, but is this the only way to do it? Will it interfere with instruments
that are controlled and read using standard LabWindows drivers? It seems to
be rather low-level commands to me.
Is there a more straightforward way of accomplishing the same with higher
level commands? Are all the ibsic, ibsre, etc. crucial in this setup? And
what about this changing the controller primary adress..
TIA
Hans D. Jensen
hdj@dfm.dtu.dk (note: a simple "Reply to Sender", won't work)