Timestamp AI with IRIG B AM Time

[CAS]

I am acquiring a number of analogue input channels (60kHz continuous acquisition) and wish to timestamp each sample with the time read from an IRIG B AM time code value. I am developing this code in C#. I am considering using the PXI-6682 device as I believe that this is the only NI device that can take the AM input. Also, I believe that I can route the sample clock of the analogue input device to the 6682 so that the time is latched at exactly the time that each analogue sample is taken (as a group).  What I'd like is some confirmation that this is correct - or some advice if it is not. My questions are: 1. Is the PXI-6682 the only NI device capable of reading in the AM IRIG B timecode signal?2. Can I daisy-chain the code to another device or is there an IRIG B output from this card?3. Can I achieve the timestamping of the analogue input sampling in the way that I described (in C#) - simultaneously reading my analogue inputs and the time values at 60kHz in a continuous acquisition? (I know how to do this for the AI without time info).4. Will I need to use any NI-Sync functions or can this be done using DAQmx functions by creating a CI Channel on my task using ‘CreateGpsTimestampChannel()’ and setting the synch method to ‘CIGpsSyncMethod.IrigB’? What format would the counter data then be in and does it represent absolute time?

Thanks in advance for any help.

[SheelaS]

Good morning CAS,

In response to your questions -

1. I can find no other NI product that will read in an IRIG-B signal, so yes this I s the only device you can use for this application

2. There is no specific IRIG-B output on the card.  However, you can set the PFI lines to output any signal on the device.  Also, if you configure PFI 0 to receive the IRIG-B signal, you can use the device as an 1588 master and output that signal to synchronize other 1588 devices.

3. The 6682 allows you to timestamp input signals, so yes you can achieve your desired timestamping.  To configure timestamping of input signals, use the niSync_EnableTimeStampTrigger function.

4. Yes, you will need to use the NI-Sync functions as the 6682 relies on this driver.

For further information, I recommend you look at the manual for the PXI 6682, available here (http://www.ni.com/pdf/manuals/372292a.pdf).  It covers all the points you have questions about.

Also, the manual for NI-Sync (http://www.ni.com/pdf/manuals/370926d.pdf) describes the functions you will need to use in your application, and has some tips for programming in different environments, as well as directions to example code.

I hope this helps, but please post back if you have nay other questions.

[CAS]

Dear Sheela,

Thanks for your reply. I will look in to those details further.

CAS