AnsweredAssumed Answered

4 channel DAC output using ADI IIO Osc on AD-FMCOMMS5-EBZ

Question asked by JippeR on Jan 22, 2018
Latest reply on Jan 23, 2018 by JippeR

Hi,

For a quick test for a beamforming project I would like to put a shifted sine on the DAC Buffer outputs(tx1,2,3 and 4) of the FMCOMMS5 evaluation board. I am using the standard linux application in combination with the ADI IIO Oscilloscope tool. I have created a data file that has entries that adhere the following structure:

TEXT

Q1,I1,Q2,I2,Q3,I3,Q4,I4

...

...

This data file first has 400 samples of silence, then starts a single period of a sinewave of 100 samples for tx1, then for tx2, for tx3,for tx4, and then another 400 samples of silence. (See attached file, and the matlab plot of the intended signal)

 

When I load these values into the 8 (4x2) channels, it says Waveform loaded successfully. However, when I take a single shot capture of the data transmitted, I only see the data from tx1 and tx2. Further inspection showed that tx3 and tx4 did send data, but tx3 is an exact replica of tx1 and tx4 is a replica of tx2. This is all done with the digital loopback of the BIST function.

 

Am I missing something, or is the tool designed to discard channels 4 through 7 and will it just use channels 0 through 3 twice for the two separate AD9361 chips? If so, how can I best achieve the described functionality in another way?

 

I have included the resulting IIO oscilloscope view and some screenshots of the Oscilloscope settings.

 

Thanks in advance

 

Jippe

Outcomes