Thanks for the advise for V-NULL, it works well.
But now another problem.
The scope measures two signals A and B, each on a seperate channel.
Waveform B is the opposite of waveform A, as displayed in the attached .jpeg file.
Waveform B is negated and build with waveform A.
The composed waveform is analysed for bit time (period and pulse duration).
There is a problem, however.
The unit under test send more than one ARINC-429 label(how many depends on the unit)
Each label is sent with a different transmit rate. Edge triggering is on signal A.
If a unit is sending a lot of labels, all with different transmit rates, you get a
B signal of a different label than of signal A, and therefor not opposite of signal A.
The period and pulse duration of the composed waveform is then irregular and unreliable.
Is there a way to solve this problem ?
