Hi Robin,
Many thanks for your help.
I created this test project to remove all the unwanted code, but I forgot to define the processor.
I have now 1 method that works fine for the acquisition of multiple channels.
I initially used the first method: "Method 1 for 1 single channel"
In the Component Inspector for AD1, I had "Static Sample Groups" disabled.
I tried to initialise SAMPLE_GROUP_SIZE to 4.
I thought I could acquire the signal from the 2 channels successively in one acquisition but this didn't worked.
I am a bit rusty in programming and I need to train seriously!
With my best regards,
Olivier