I have not yet purchased the U6 because I want to make sure it can do what I want it to do first.
I want to sample two analogue channels. Sampling should be done each time a digital input goes high. The frequency is about 6000 Hz.
I also would like to be able to start the sampling when another digital input goes high.
1. Wait for digital input 0 to go high.
2. Sample analog channel 0 and 1 each time digital input 1 goes high (about 6000 Hz).
3. After a preset number of samples, stop sampling.
I want to do the programming in VB.net. I downloaded the DotNET_LJUD zip file and started looking around but I cannot find good documentation for the API anywhere.
Can anyone summarize shortly how the application above could be implemented (pseudo code).
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2. This is going to require the ability to stream off an external clock. The U6 can't do that, but the T7 can. See the registers STREAM_CLOCK_SOURCE and STREAM_EXTERNAL_CLOCK_DIVISOR:
https://labjack.com/support/datasheets/t7/communication/stream-mode
https://labjack.com/forums/t7/externally-clocked-stream
1. You can poll the DI to wait for it to go high, and then start the stream, or on the T7 you can use the register STREAM_TRIGGER_INDEX to do this in hardware.
3. This is also supported in hardware on the T7 and we call it stream-burst. See the register STREAM_NUM_SCANS.
FYI: The documentation for the UD library for Windows is in Section 4 of the U6 Datasheet:
https://labjack.com/support/datasheets/u6/high-level-driver