Can I aquire digital and analog data at the same time on a PCI-1200

[JustinGardner]

This is rather a basic question, but I have a PCI-1200 board and I want to aquire digital and analog data continuously at 1 khz. Is this possible?

For instatnce, is it possible to have the A0 clock output sent to one of the other counters on the board (say B0) which has an output accessible externally and then wire that pin to be the handshaking signal for digital aquisition?

Any help would be greatly appreciated.

Thanks,

Justin Gardner

[RIO-Todd]

Justin,

The 8255 only supports handshaking and what you are wanting to do is more pattern digital I/O. You can somewhat trick the 8255 (digital counter/timer chip onboard the PCI-1200) to perform pseudo digital pattern input/output by just tying the clock of your analog output to the STB pin within Port C (control lines) of the 8255. You would could ignore the other handshaking line of the 8255 (ACK). Whenever the STB pin pulses the digital data would be latched and inputted (similar to pattern I/O). This should work if you keep the rates somewhat low (1 kHz should be slow enough).

I've included a couple links below. One explains the 8255 chip in more detail and the other is the user manual which you can use to get all of the connection information. I h
ope this helps.

Understanding the Bi-Directional Mode of 8255 Chip
http://digital.ni.com/public.nsf/websearch/F865C1157622C9DE8625648B00782CDA?OpenDocument

NI PCI-1200 User Manual
http://digital.ni.com/manuals.nsf/webAdvsearch/7CB847844CDA2A0E86256BCD0072C7DA?OpenDocument&vid=niwc&node=132100_US

Regards,

Todd D.

[JustinGardner]

Todd D.

Thank you so much for your answer. The links and your explanation are very helpful. I think I understand the situation a little better now.

There is one thing I still don't understand. I am not sure what pin on the PCI-1200 is the clock for the analog input. The manual says that this is clock A0, but I couldn't locate any connector pin that would give me access to that clock. Am I missing something?

Alternatively, is there a labview way to make one of the other counters on the board count the output of clock A0 and then make the results of that available on its output (it seems like clocks B0-B2 are available as connector pins).

Sorry for the added questions, and thanks again for your reply.

-justin

[RIO-Todd]

Justin,

There actually isn't pin on the PCI-1200 that will have the clock for analog input. What you will have to do is use a counter on the device to generate a 1 KHz pulse train. You will then configure the analog input to use an external clock and route (or wire) the counter output to the EXTCONV pin for analog input and the STB pin for the digital input. The document linked below might help. Good luck.

How do I Synchronize the Analog Input with the Analog Output on My DAQCard-1200?
http://digital.ni.com/public.nsf/websearch/8683A17AED4FDBAB86256C1E006D3BBA?OpenDocument

Regards,

Todd D.

[JustinGardner]

Oh, right. Of course. That makes sense. Thank you very much for your help.

-justin