Use cDAQ9174 and NI9401 module to generate two double pulse waveforms

[zkli]

Hi, all

I want to use NI9401 to achieve dual-channel double pulse output. My implementation is to add a channel 2 to the existing single-channel (channel 1) output that has been successful and use the same clock frequency and pulse logic. But in this case, an error message of error50103 will appear. How can I solve this problem? The program has been attached, please check and correct.

Many thanks

[NPowl · Accepted solution]

Hi Zkli,

DAQmx Error 50103 states "Possible reason(s): The specified resource is reserved. The operation could not be completed as specified.". DAQmx reserves the module when you call it to create a task; you'll need to assign both channels on the same task. You can select multiple channels from one module by calling a series, e.g. "Dev1/port0/line0:1" or explicitly calling out the specific channels "Dev1/port0/line0, Dev1/port0/line1".

You'll need to change DAQmx Write to be Digital NChan NSamp and write an array, where each element in the array corresponds to a channel in the task.

Cheers,

Nick

[zkli]

Hi Nick,

It works!

Thank you very much for your suggestions, I have already fixed this problem with your methods. 

Kind regards,

ZK