Hi Pao,
What you want to do is possible with a retriggerable single point analog input acquisition. The analog input would be set up to grigger on the digital line and take the data when it goes high. Then in software, it will re-setup the acquisition and take another point when the signal goes high. This method only works when you have a relatively slow re-occurring trigger signal. This is because the time between each trigger signal cannot be shorter than the time it takes the software to set up the acquisition after each trigger.
You may also be able to route the digital trigger signal to the scan clock for the acquisition. You would set up your acqu
isition as a continuous analog input. The trigger signal would need to be wired to one of the PFI lines on your MIO board. In software, you would route the trigger signal as the scan clock for the acquisition so one data point is taken with each pulse of the trigger signal. This type of setup would also work for a fast trigger signal.
Thanks,
Sal