I posted this message on the VB6 message board. I'm using VC++
Hi,
I'm trying to capture data on 2 usb-6009 devices simultaneously. I have set up the two DAQs as follow.
1. Using a function generator, generate a sine wave that is slower and not a multiple of the sampling rate (48KHz) and apply it to the odd numbered channels.
2. Connect the even numbered channels to ground.
3. Connect the PFI0 of each to a digital output of one of the DAQs.
4. Set up each DAQ to sample as fast (48KHz) as possible and trigger off of the PFI0 input.
5. Generate the digital output trigger - software write to "Dev1/port0"
6. Read the resulting samples and determine the difference between each of the odd channels between the DAQs in a given sample set.
My results are not as expected. Using Excel to plot the data I see that the data of the 2 DAQs are shifted on every sampling set.
I have verified on scope that the trigger works and that both got triggered. I think the above setup is not complete and I think I need to
setup both DAQs to share the same source clock but I do not know how to setup 2 DAQs to share the same clock. My questions are
1) Is my setup above ok?
2) if need to setup 2 DAQs to share the same clock, how to set it up?
3) Is it possible synchronize 2 usb-6009 devices?
Thanks,
Tuan
