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digital trigger for analog scan

I need to synchronize the start of several measurements with a trigger. I am using a NI 4472 input card and PCI-6731 output card. I need to trigger an analog scan on the 4472, a voltage output from the 6731, and trigger a dmm to start scanning with a digital output from the 6731.
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As far as triggering the 6731 cards, take a look at some of the LabVIEW triggering examples.

In LabVIEW go to Help >> Find Examples >> Hardware Input and Output >> DAQmx >> Analog Generation >> Voltage >> Cont Gen Waveform-Int Clk-Dig Start.VI

This example program uses digital line trigger to start the acquisition. There are also examples for the output to start with an analog trigger. You can use one of the analog input cards to trigger the acquisition, or you can use the RTSI lines to synchronize the trigger across several boards. What you would do to use the RTSI lines would be to use the rout signal VI's to route the trigger signal to an RTSI line on the board that is recieving the trigger. The other board would be set up to trigger on th
e digital edge of the RTSI line. You would need an extra cable for this (RTSI cable that is sold by NI).
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To trigger acquisition on the 4472 from a DIO line on a 6731, you would need to follow recommendations similar to Sal's. You could route the DIO line to a RTSI line on the PXI backplane, and then set up the 4472 to trigger acquisition off that RTSI line. You could also use an external connection and wire the DIO line to the "External Trigger" input on the 4472, and configure it to trigger off that signal. Probably the most important thing for you to do is make sure that everything that you want to trigger off that DIO line is setup and waiting for it before the trigger occurs.

You can also use the example finder to find examples that will work with each individual device. In the bottom left-hand corner of the LabVIEW example finder, there is a button that you
can click on to select or add the different pieces of hardware you want examples for. After you have configured that correctly, if you limit results to that hardware (check box), the only examples that you will see will be work with that piece of hardware. There are numerous examples of triggering on a digital line for the 4472. Hopefully this get's you moving. Good luck!

Logan S.
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