DAQ programming

[johnsold]

The problem is that the Sampling info (on the Square Waveform.vi) is set to 1000 Samples/second and 1000 Samples. That only gives 1 second of data. Change the values and you can generate much lower frequencies.

Lynn

[GERECC]

Hi all, thanks Lynn for pointing out my mistake. I am running into this another problem. I am using this BNC-2110 block and PCI-6036E to acquire the signals. However,after testing out each signals, I started to put them together to run at the same time. Now, the problem arises. I found there are interference among each channels. For example, if one of the channel has a square wave input, all the other channels will have a square wave ripple added onto it's own signal. This is messing up my data and some DC offsets (unwanted) are added to my signals too.

Not sure if I should post it up here on this forum, or it should go to the DAQ forum. But please advise if you have any insights. Thanks a lot!

[johnsold]

Perhaps the DAQ forum would be a good place. It sounds like you may have crosstalk. If you have any channels which are not used, ground the inputs. Floating inputs can cause strange things to happen. Similarly if any of the signal sources have high output impedances, buffering may be required.

Another common problem is differing ground potentials between signal sources or between the source and the computer.

Also make sure the inputs to the DAQ card are properly terminated. Check the help files for information about your card.

Lynn