LabVIEW

cancel
Showing results for 
Search instead for 
Did you mean: 

FPGA and External Clock Source

Hello,

I am new to FPGA world and trying to use an external clock for NI PXIe-1073 that has a PXI-7851R IO. I tried to feed the clock signal using a digital input, but the digital input does not show up in the clock options of time loops in labview FPGA.

I would appreciate it if you could help me in this issue.

Thanks,

Masoud

0 Kudos
Message 1 of 4
(3,328 Views)

Hey Masoud_A,

 

Take a look at this forum post for some more information on this:

 

https://forums.ni.com/t5/Real-Time-Measurement-and/Timed-Loops-with-External-Clocks/m-p/2209902/high...

 

The short answer is that this is not supported on our R Series cards. However, the workaround posted in that forum post should be a good start.

 

Cheers,

Ryan C.

0 Kudos
Message 2 of 4
(3,236 Views)

Hi Ryan,

 

Thank you for your answer. I checked that forum and I don't think using a SCTL to sample the external clock into a local variable will provide the accuracy that I am looking for. Is there any new IO that provides an external clock option?

 

Thanks,

Masoud

 

0 Kudos
Message 3 of 4
(3,229 Views)

Hi Masoud_A,

 

What do you think about sampling and then using the case structure without a local variable?

 

The forum post is also up-to-date about the I/O. There aren't currently any R Series or Compact RIO devices that support the external loop timer.

 

Cheers,

Ryan

0 Kudos
Message 4 of 4
(3,207 Views)