Observations:
When acquiring data from the SCXI Chassis 1122 modules, using either MAX or LabVIEW example VIs, the computer requires 100% of the processing power as indicated by the Task Manager (little more than 5 Mb memory is utilized from the 64 Mb available). When the system begins sampling, the system does not crash, rather it bogs down; multiple seconds between clicking something and any response. There is no observable difference between sampling one channel and multiple channels. Sampling all forty -(40) thermocouples in the SCXI 1102 modules requires less than 7% of the system resources, according to the Task Manager. The 1122 modules contain K-type thermocouples, 4-20 mA, 0-5 VDC, and 0-15 mV signals
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To isolate the problem, all modules were removed except one 1122. After reconfiguring the software, the problem persisted, regardless of using MAX or sample VIs. Fearing that corrupt signals were causing the problem, a spare terminal block with a single K-type thermocouple replaced the existing terminal block; the problem remained. Switching the module with a recently calibrated (9-12-01) 1122 did nothing to effect the problem.
System Information:
Win NT (ver 4 with service pack 5)
Pentium III 733 MHz (Dell)
LabVIEW 5.1
SCXI Chassis 1001
2 - SCXI 1122 modules with 1322 terminal blocks
2 - SCXI 1102 modules with 1303 terminal blocks
1 - SCXI 1160 module with 1324 terminal block
1 - SCXI 1124 module with 1325 terminal block