TimerPulseOut Question

[C. Drutman]

I am trying to run the TimerPulseOut.c program, and no matter what I enter for the frequency, I measure ~114 Hz on my scope. The default value for the frequency is 1,000, and building and running the program gives ~14 Hz. If I change the frequency to 10 and rebuild and run, I still get ~14 Hz. Any suggestions? Thanks.

[Fausto]

Which MCC device are you using?

[JRys]

Works with my USB-1608G. I tested it at 1000 and 8000 Hz - no problem. Make sure to screw a wire into the terminal to attach the scope probe to. Probing the screw terminal tops will have mixed results.

John

[Fausto]

Hello @C. Drutman.

I tested a USB-1608GX-2AO module with MCC's UL for Linux and the 'TmrPulseOut.c' example worked as expected.  The TMR and GND terminals were connected to an oscilloscope and displayed a 1 kHz pulse output.

Which OS and Universal Library API version are you using?

Regards,

Fausto

[C. Drutman]

On 12/30/2022 at 2:24 PM, Fausto said:

Hello @C. Drutman.

I tested a USB-1608GX-2AO module with MCC's UL for Linux and the 'TmrPulseOut.c' example worked as expected.  The TMR and GND terminals were connected to an oscilloscope and displayed a 1 kHz pulse output.

Which OS and Universal Library API version are you using?

Regards,

Fausto

I am using the USB-2627 with the ULDAQ-1.2.1 API. The TMR0 and AGND are attached via alligator clips to a BNC which connects to my scope. Someone suggested that I need to set the sampling rate of the board, but I did not see a call like that in the API or any of the examples.

[JRys]

I clipped my scope probe onto pin 33 on the J4 header connector and the TmrPulseOut.c example worked as expected, I got an 8000 Hz square wave. 

double check your connection and maybe try the other timer on pin 32.

And, there is no need to set a sampling rate.

[C. Drutman]

18 hours ago, JRys said:

I clipped my scope probe onto pin 33 on the J4 header connector and the TmrPulseOut.c example worked as expected, I got an 8000 Hz square wave. 

double check your connection and maybe try the other timer on pin 32.

And, there is no need to set a sampling rate.

Not sure what changed, but this morning everything is working as advertised. Thanks everyone for all your inputs.