external trigger to vxi controller

[Donald R. Bagwell]

I could use help on developing code to use the "trig in" pin on the front
of a vxi controller.
once a trigger is received, I want to call a routine, to tell a vxi-dio128
digital card to read
the data from 2 ports. I'm sure this involves interrupts, of which I have
limited
experience. But any help would be greatly appreciated..

[Trey_Hamilton]

Donald,

There is a page on our website written as an introduction and description of triggers in NI-VXI. It includes information about mapping trigger lines to the TrigIn pin so that you can synchronize your data acquisition function.

This page can be accessed by searching http://www.zone.ni.com/ for "Triggering with NI-VXI" or by going to this URL:
http://zone.ni.com/devzone/devzoneweb.nsf/opendoc?openagent&0DED2E0927C332418625688600611AE7&cat=3B9A19E3932BF7678625681F006D511B

If you are using VISA 2.5, you will want to open a session to the Backplane resource. You can then use Visa Map Trigger to map the TrigIn pin (27) to one of the TTL lines (0-7). The DIO128 can then be configured to use this TTL line as a trigger to begin acquisition.

I hope this helps
. It may also help in the future if you have inquiries that are related to VXI systems that you post them to the VXI newsgroup. It is more likely that someone with experience in what you are working with will see your request.