I found out that the virtual channel system is kind of problematic with my system. One of the NI engineers recomended me to use those, specially because they perform CJC on every reading automatically, and I did. But I wasted a lot of effort just to discover that the AI Read VI doesn't update the CJC on every reading, what is done only in the setup.
Here is the spec of my systgem:
- SCXI-1000
- SCXI-1200 connected in the parallel port and controling the chassis, with connector block 1302, and using its counter resources.
- SCXI-1163, controling a few switches with connector block 1326
- SCXI-1120, reading T thermocouples, with connector block 1327.
- LabVIEW 5.1f1
- NI-DAQ - 6.9.1f28
- IBM Personal Computer 300 GL, with Pentium II 266 Mhz.
I dicover
ed that the Virtual Channels weren't that good using the "SCXI Scan VI", provided with the package. I configured a single virtual channel and started an acquisition, returning me NaN. Then, using the SCXI Scan VI and configuring everything manually, I could get some results. I have tried so many things to get it working that the possibilities are almost over.
Anyway, the error I get most is code 10800. I tried to slow down the Scan Rate, increase the samples/channel, increased the time limit, checked all jumpers, reduced the gain, set the same gain for all channels, connecting and not connecting "-" channel to ground, tried to split the daq into 2 readings of 4 channels instead of 1 of 8, (and maybe some other things I can't remeber now) and nothing seems to work. The other modules work well. Also, it's important to say that I got the same DAQ problems with the VIs provided with LabVIEW. A funny thing is that some times, the DAQ works, sometime, it doesn't. Of course, I am comparing
in exactly the same conditions, i.e., turning everything ON, then first loading LabVIEW and starting a acquisition. This is really strange.
I hope anyone can help me!
Thanks,
Guilherme