I have been using the 6020E USB for about 6 months witout incident on an experiment. It is connected to a Dell laptop (2.4Ghz) and I am running LabWindows CVI (V6). I have it setup running 8 Diff channels in Async Double Buffer acquisition mode. Recently it seems to just stop sending data into the bufffers for no apparent reason. Sometimes it runs for the whole day, sometimes for 1 minute. I believe it is a USB problem as it blue screened once and said someting about USB and a device driver conflict, also if I pull the USB cable i get the same effect (program keeps going fine, but no data).
Here are a few thoughts I have as to the problem, however they are hard to test because of the randomness of the stopping:
- Win XP SP2 issue (it was recently installed)
- The laptop was recently moved onto a domain from a workgroup?
- Bad cable (although I jiggled each end pretty hard and it kept working)
- NI-DAQ V 7.1 is currently installed (I am downloading 7.4 as I type this)
The only other clue I have is if the program is running fine and I open Meas Automation Explorer and click on test resources for the 6020E, it stops the DAQ in the program. Below is a snippet of my code, thanks in advance for any help!
Cheers - Andrew
// Setup the DAQ
AI_Configure (0, -1, 0, 10, 1, 0);
Timeout_Config(iDevice, lTimeout);
DAQ_DB_Config(iDevice, iDBmodeON);
SCAN_Setup (1, iNumChans, chan_list, gain_list);
status = SCAN_Start (1, piBuffer, SAMPLES, 1, 10, 4, 0);
if(status < 0)
{
MessagePopup ("error", "daq start failed");
return 0;
}
while (DAQquitflag == 1)
{
DAQ_DB_HalfReady(iDevice, &iHalfReady, &iDAQstopped);
if (iHalfReady == 1)
{
DAQ_DB_Transfer(iDevice, piHalfBuffer, &ulPtsTfr, &iDAQstopped);
SCAN_Demux (piHalfBuffer, SAMPLES_half, iNumChans, 0);
DAQ_VScale(iDevice, iChan, iGain, dGainAdjust, dOffset, SAMPLES_half, piHalfBuffer, pdVoltBuffer);
// Do some other stuff...
}
}