multiple sequential pattern match in a HSDIO acquisition app

[jon]

I am quite a newbie about HSDIO apps and I would like to implement a
start-triggered app via Pattern Match. I wonder if I could recognize a
sequence of pattern matches (various samples) in order to start a
generation.

I use a NI-6541 device.

Thanks a lot.

[Matt_A]

Hello Jon,

I'm a little confused about your question, so maybe you can clarify some information. What do you mean when you say that you want to use pattern matching to start a generation? Since the generation has not started, there will be no signal to match to the pattern. Are you saying that you want to acquire on one port and then generate data on another port based on matching a pattern on the acquisition? If so, this should be plausible based on the ability to export the trigger from the acquisition to the generation portion of the session. I also wanted to know what version of the NI-6541 you are using? PCI or PXI?

Let me know if I'm understanding your question, and I can provide some more details. I will poke around with this application and see what I can figure out.

[jon]

Hello Matt,

Well, I'm sorry for the fact of being confusing. I'll try to clarify:

> ... Are you saying that you want to acquire on one port and then
> generate data on another port based on matching a pattern on the
> acquisition? ...

Yes, this is what I want to do. Also, sample clock is a external
signal (20MHz) connected to 'STROBE' pin. Generation and acquisition
sessions both use the same sample clock. Acquisition port has 2 lines/
inputs (dio28, dio29) and generation one has 28 outputs
(dio0..dio27).

Well, I have to do the following process (let's cross fingers):

1. When one '0' is detected in dio28 line, then device must wait until
dio28 is '1' and dio29 is '1'. There's no generation between these
events.

2. After that, a generation of a certain waveform is performed at
once, up to a certain number of samples in lines <dio0..dio27>. then,
dio29 is '0'.

3. Finally, pseudocoded: 'wait until dio28=1 and dio29=1. Then, go to
step 2 with another waveform parttern.' Device ends when 288 diferent
waveforms are written.

> ... I also wanted to know what version of the NI-6541 you are using? PCI or
> PXI? ...

PXI.

I hope to be more accurate.

Many Thanks In Advance

[Matt_A]

Hello Jon,

You should be able to perform the operation you described by exporting the pattern match trigger in your acquisition session to start your generation session. The example program "Dynamic Generation and Acquisition-Source Synchronous.vi" demonstrates this process. For more information about this example you can check out this [link removed; article no longer available] document on our website. You would need to change the trigger type on the acquisition to Pattern Match Start Trigger, but this example should give you a good place to start. I hope this information is helpful, let me know if you have any other questions.