Why the board behaves diffrent in "Labview" and "Measurement & Automation"

[pci]

DAQ:PCI-6111E
"LabView" Ver. 6i
"Measurement & Automation" Ver 2.0
Windows98SE

When the board is set to generate continuous sinewave with the example "Generate Continuous Sinewave.vi",
the annalog output is OK,here is the result===update-rate(frequency of sine on oscillograph)
4000000(4000Hz),3750000(3750Hz),3500000(3500Hz),3250000(3250Hz),3000000(3000Hz),2500000(2500Hz),2000000(2000Hz),1500000(1500Hz),1250000(1250Hz),1000000(1000Hz)
while in "MAX(Measurement & Automation)",the "actual" sine wave output is "not always" 1/1000 of the update rate,
even not a direct proportion is found,here is the result===update-rate(frequency of sine on oscillograph)
3750000(2500Hz),3500000(2500Hz),3250000(2500Hz),3000000(2440Hz),2500000(2440Hz),2000000(1666Hz),1500000(1666Hz),1250000(1220Hz),1000000(1000Hz)
3750000 is the upper limit,and MAX will report error for digits beyond 3750000.
What is wrong?

[Salvador_Santolucito]

Hi,

You are probably noticing a discrepancy because the analog output code that MAX uses is a simplified version. The purpose of the MAX test panels is to simply verify whether or not the board is functioning. It is not intended for highly accurate analog output. I would say that your board is working fine since your LabVIEW code generates accurate output.

Another thing to look at is your MAX version. We are up to MAX 3.1.1 now. I would suggest upgrading your NI-DAQ driver. For Windows 98 you need NI-DAQ 7.1 found here:

http://digital.ni.com/softlib.nsf/websearch/C1F802E457EA042586256DD00001B0C9?opendocument&node=132060_US


-Sal