Problem with oscilloscope of ADP when the range is <2 V

[Mathias G.]

Hi @attila !

I try the single mode, generally that's works, but sometimes (even half the time) the acquisition have an easily observable problem (pictures 1 and 2. This problem only happens when I have a range less than or equal to 2 volts. I notice that the signal amplitude has been reduced x25.

I see with Waveforms that the signal amplitude is egal to 0.33 and doesn't vary.

Edited June 30, 2023 by Mathias G.

[attila]

Hi @Mathias G.

This may be caused by the range-relay switching.
By default on device open and close from software the inputs and outputs are stopped, reset to high range, zero offset... and all settings applied for each *Set call.
- use the following before device open to keep the setting (relays, offsets..) after device close
dwf.FDwfParamSet(DwfParamOnClose, c_int(0)) # 0 = run, 1 = stop, 2 = shutdown
- use the following after device open
dwf.FDwfDeviceAutoConfigureSet(hdwf, c_int(0))# 0 = the device will be configured only when calling FDwf###Configure
- or use about 0.01-0.1 second delay after analog-out configuration

[Mathias G.]

37 minutes ago, attila said:

Hi @Mathias G.

This may be caused by the range-relay switching.
By default on device open and close from software the inputs and outputs are stopped, reset to high range, zero offset... and all settings applied for each *Set call.
- use the following before device open to keep the setting (relays, offsets..) after device close
dwf.FDwfParamSet(DwfParamOnClose, c_int(0)) # 0 = run, 1 = stop, 2 = shutdown
- use the following after device open
dwf.FDwfDeviceAutoConfigureSet(hdwf, c_int(0))# 0 = the device will be configured only when calling FDwf###Configure
- or use about 0.01-0.1 second delay after analog-out configuration

Hi @attila !

Thank you, the problem was dwf.FDwfParamSet(DwfParamOnClose, c_int(0)) :)