RT Measuring with 9220 and 9222 at different sample rates

[enricoB]

Hello,

I need to sample analog data with c-Series Modules NI-9220 with 100 kS/s and NI-9222 with 400 kS/s. As far as I know I have to use User-Controlled I/O Sampling Functions.

If I adapt the NI examples of NI-9222 I will get a timeout error by Invoke Method FIFO.Read.

Can anyone explain and may help please?

(The less speed of NI-9220 I will later get by a case-structure in combination with a counter and the "Generate I/O Sample Pulse Method")

[TSE_Expert]

Dear enricoB,

is the generated error code -50400?

If yes, there are two possible root causes which might cause the problem:

1. The FIFO is not getting written to. This might happen because you aren't actually acquiring data, or updating data in your FPGA program. You can check if data is properly received by wiring indicators to the inputs of your FIFO Write in the FPGA program.

Or:

2. The host program is timing out before the FPGA program has a chance to write to the FIFO. Increase the timeout of the FIFO Read method on your host program.

Take a look at this article too:

https://knowledge.ni.com/KnowledgeArticleDetails?id=kA00Z000000kG75SAE

Best Regards,

NI TSE