Vxi triggers and interrupts with CVI

Question

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..

Answer 1

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.
Trey Hamilton
Appl
ications Engineer
National Instruments
http://www.ni.com/ask