Eclypse Z7 Zmod AWG Play function

[dmangione]

I have a custom waveform (6225920 points @ 4.1 MHz) that is larger than the buffer size allowed with the custom function (65535 points). The play function seems like the solution to this, so I have used the AnalogOut_Play.py demo provided with Waveforms as a reference for implementing it. I am using an Eclypse Z7

Unfortunately it keeps failing at the FDwfAnalogOutNodePlayData function. To double check it wasn't my code, I tried running the unmodified AnalogOut_Play.py, and used a mono 1kHz tone, 44.1kHz sample rate, +/- 1 V, 30 second, wav file as "audio.wav". This also failed at the same function, so it's not a problem with my implementation. The function doesn't provide any error message, but this is the output:

Load audio.WAV file
Rate: 44100
Size: 1323000
Type: int16
Scaling: INT16
DWF Version: b'3.21.3'
Opening first device...
Playing audio...
Length: 30.0
Error
Lost: 17
Corrupted: 0
done

As a further check, I've tried playing the audio file using the Waveforms GUI. The program fails, and mentions that the error is again with the FDwfAnalogOutNodePlayData function. This error will keep popping up and requires a restart of the program.

 

Is the Eclypse Z7 Zmod AWG known to work with the play function? I am able to generate any standard function and even custom waveforms using both the GUI and the SDK via Python, so I am not sure what else could be wrong.

[attila]

Hi @dmangione

It is fixed in the latest version:

 

[attila]

Hi @dmangione

The play and record are limited by the USB/ethernet streaming rate if the length exceeds the device buffer size.
On Eclypse oscilloscope capture buffer 256Mi samples total and AWG carrier buffer / channel 64ki (1 AWG Zmod w 2ch) or 32ki samples (2 AWG Zmods w 4ch)

[attila]

Hi @dmangione

In the latest version the play/streaming rate is improved.
Now, with EclypseZ7 I cold reach about 3MHz. Above this samples are lost due device buffer underflow.

 

[attila]

Hi @dmangione

The Play stopped working when the DDR RAM oscilloscope buffering was introduced and the AWG buffer size was increased.

It will be fixed in the next version.
Thank you for the observation.

[dmangione]

5 hours ago, attila said:

Hi @dmangione

It is fixed in the latest version:

 

Great, thank you! The play function works on both the GUI and the demo scripts.

I have notice though, that at higher output frequencies a significant amount of the points are lost (Mhz range). I assume this is from the output being faster than the buffer can load new points from the computer. Do you know if this is a limitation of the USB interface, or a limitation of the software?

[dmangione]

Hi, @attila

I wanted to follow up on an error I've noticed with the play function on the Eclypse Z7. Using both the Waveforms program and the WF SDK, my signal (custom 4.1 MHz waveform) has occasional discontinuities, circle below in red. Note that I am streaming via ethernet. It appears that the output voltages shifts ~50 mV, but the waveform otherwise stays intact. Is this a consequence of streaming data for MHz-range output, or is this fixable via software?