No Error Message and Program Won't Run

[Chuck@Eaton]

I just started using DasyLab 2022 and am really having fits with it.   I have a simple signal generator outputting a sine wave at 1Hz connected to an analog output to my PXI-6255 card.   The card is connected in a PXI-1050 chassis (Old MX1 configuration).  I have configured the PXI card in several different ways (1 Sample (on demand), N samples, and continuous) and resynched in DasyLab for Resetting task settings changed in DasyLab.   At one point I was able to get an output sine wave (Can't remember the settings) although it had a bad stairstep but now when I hit run, nothing happens and no error message.  If I connect the signal generator to just a display output, it works fine so there must be something in the hardware configuration I am missing.   Will appreciate any help on this.

[john@MCC · Accepted solution]

Hello Chuck,

Using NI's MAX, configure the task for continuous operation without any special triggers like an analog input level or external TTL. Set the task to run at 1000 S/s. If there is a transfer block size or packet size set it to 100.  Save & close the task and jump back into DASYLab. Start a new worksheet and drop a DAQmx Analog Input module down. Link it to your updated task and connect it to a y/t Chart display and run. You may have to play with the X-Axis setting to see a 1 Hz sine wave.

Hopefully this helps. 

John

[Chuck@Eaton · Accepted solution]

Hi John.  That definitely helped.  I thought I had it set up that way at one time but anyway it is working now for the input (AI0 into Input Module DA00) and feeding an output (AO0 out of module DA01).   

The new related problem is that I have the output (AO0) physically wired to another input (AI6 into Input Module DA02) and that input is set up the same as the other input (AI0) but DasyLab is not seeing the signal.   Again, the signals all look good in MAX as I am able to simulate the output and the input is there, as well as verifying the signal with a separate oscilloscope connected.   See attached for the DasyLab worksheet screen shot.  Any ideas of what I am doing wrong?

[john@MCC · Accepted solution]

Hey Chuck,

Create a task that has both Ai0 & Ai6. Modify the top Analog Input so that it outputs both channels. Connect the Ai6 over to your y/t Chart for display. I'm not sure what's allowed and what isn't, but I'm guessing that there can be only one analog input task can be used at any one time. I'm not sure if you can use the same task in two separate modules. It may allow it but that would for very slow rates where the hardware's A/D scan circuit is not used.

John

[Chuck@Eaton · Accepted solution]

Hi John,

Thanks, that works.   Another question, when I switch between the worksheet and the layout the program stops.   Not a big deal but seems strange that it would do that.