Analog Discovery 2 custom waveform output limitations

[isaacz]

Hello,

I am trying to use the custom output on wavegen in analog discovery 2 to output a signal with 8192 samples. Through testing and measuring with the scope, I am having trouble getting the measured output to match the input. In the simplest case I observe that a custom signal (consisting of alternating -1 V to 1 V samples) of length 4096 outputs correctly, however once I generate the longer signal with 8192 samples, the output seems to be dropping samples. In the case where I used simple -1 V to 1 V alternating data samples, with length 4096 I could see the output on the scope, but length 8192 there was no signal measured at output (constant 0). My other observation is that changing the sample frequency has no effect on the integrity of the output signal.

I have included the workspace which has both the short and the long custom signal. Any help or explanation to why the longer signal is not working would be greatly appreciated.

Best

test_workspace.dwf3work

[attila]

Hi @isaacz

Use the 3rd device configuration with more Wavegen buffer or for even more samples at lower rate use the Wavegen/Play option.

[isaacz]

On 7/28/2023 at 3:32 PM, attila said:

Hi @isaacz

Use the 3rd device configuration with more Wavegen buffer or for even more samples at lower rate use the Wavegen/Play option.

Thanks for your answer, this fixed the problem of samples dropping at the wavegen output. I am wondering, however, if there are any other configurations to choose from? By selecting configuration 3, it seems like patterns cannot use a custom waveform, but for my application I was hoping to have a small pattern (1 channel, ~100 samples) output concurrently with the 8k samples. I tried using "Play" and it works for some time, but occasionally samples will drop using this option.

Best,

Isaac

[attila]

Hi @isaacz

The available configurations are the ones listed by the application.