Multiple ADALM1000 Boards and ADC Synchronization and Triggering

Question

I am using trying to use 2 ADALM1000 boards to do the following: 1 board is generating an output voltage waveform (HI_Z, CHA), and the second board is configured to read that voltage waveform with both channels in order to test if they can be truly simultaneously sampled as I understood from the documentation. However, I am observing a phase shift (CHA is slightly lagging CHB by a few degrees), and the boards are not phase locked. I have the second board setup as 2 HI_Z channels and reading CHA and CHB. Shouldn't these ADCs be simultaneously sampled since they are 2 separate ADCs, and if not, is there anyway to make them simultaneous and allow for accurate in time measurements of the 2 channels? 
 Also, is there anyway to create a trigger pulse from the first board and use that as a trigger for the second board to have it phase locked with the DAC voltage waveform (right now I'm trying with a simple sine wave)? I could even use the second channel (CHB) to generate a pulse if that would work, and read that from a trigger, but I don't see any provision for triggering. 
 Thanks in advance, 
 Walid

WalidK · Accepted Answer

For clarification, the below plot shows the phase shift I am seeing when using a 1kHz sine wave drive connected to both CHA and CHB IN--it appears to be a phase shift of exactly 1 sample number which is 10usec (sample rate is 100kHz). The code that reads this is simply using: 
 
 samples = dev1 .get_samples( waveform_samples * 100 ) 
 chan_a = [ item [ 0 ][ 0 ] for item in samples ] 
 chan_b = [ item [ 1 ][ 0 ] for item in samples ] 
 
 I'm really hoping that 2 ADALM1000 boards can be phase locked as well as having the 2 channels on a board simultaneously sampled. 
 Thanks, 
 Walid)

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Multiple ADALM1000 Boards and ADC Synchronization and Triggering