Questions about waveform generator

[CyLab]

Hi, 

Thanks for the great and convenient product firstly!

I have a problem in using analog discovery 2 to generate pulses. As shown in the picture, where I used another analog discovery 2 to measure a circuit which driven by an analog discovery 2. You may find that after the pulses I intend to generate, the output voltage will maintain in the peak level of pulse instead of the final voltage or zero.

The experiment that I am working on is rely on the voltage applying time. Is there any way to make the analog discovery 2 not to maintain the peak voltage or simply stay in the ground level when there is no assigned voltage? 

Thank you so much for your time！

[attila]

Hi @CyLab

You can use negative amplitude for pulse.

The idle option lets you specify offset or initial value. The disable/0V option is not available for AD2 since the offset has relatively long settling time, compared to the MHz bandwidth.

[CyLab]

9 hours ago, attila said:

Hi @CyLab

You can use negative amplitude for pulse.

The idle option lets you specify offset or initial value. The disable/0V option is not available for AD2 since the offset has relatively long settling time, compared to the MHz bandwidth.

Hi,

Thanks for the reply, actually we are using Matlab to control the device for the flexibility of waveform. And we found that the offset value is as same as the initial value of the signal we generated.  After modifying the initial value of the signal, old problem solved and a new fatal one arisen, the wanted pulse is in the green circle and anomaly is in the blue circle. I will try to use WaveForm later and see if the problem still exist. Thanks again for your help!

[attila]

Hi @CyLab

I'm not sure what sequence of functions are you using to configure the analog-out (Wavegen).

Normally after calling any set functions the device gets configured 'automatically'.
You can disable this option to configure the device only when calling FDwfAnalogOutConfigure, after all the settings are set.
This option applies to all the instruments, analog/digital-out/in/io 

dwf.FDwfDeviceAutoConfigureSet(hdwf, c_int(0)) # 0 = the device will be configured only when calling FDwf###Configure

dwf.FDwfAnalogOutNodeEnableSet(hdwf, channel, AnalogOutNodeCarrier, c_bool(True))
dwf.FDwfAnalogOutNodeFunctionSet(hdwf, channel, AnalogOutNodeCarrier, funcSine)
dwf.FDwfAnalogOutNodeFrequencySet(hdwf, channel, AnalogOutNodeCarrier, c_double(1000))
dwf.FDwfAnalogOutNodeAmplitudeSet(hdwf, channel, AnalogOutNodeCarrier, c_double(1.41))
dwf.FDwfAnalogOutNodeOffsetSet(hdwf, channel, AnalogOutNodeCarrier, c_double(1.41))
....

dwf.FDwfAnalogOutConfigure(hdwf, channel, c_int(1)) # 0 stop, 1 start, 3 configure and continue running in case it is running

 

[CyLab]

Hi @attila,

That sounds great! It seems that we can use python to control more options in the AD2 and I also found py examples in the WaveForms package. So besides examples, I am wondering if there is a manual introducing how to use python or matlab for AD2?

Thanks!

[attila]

Hi @CyLab

You can find the manual in the WF SDK/ manual folder, two directories up from the python examples.