Hi List,
When the SIMtrace ciruit operates in MitM mode, the RST and VCC lines
coming from the phone are very noisy from I/O line crosstalk in the flex
cable.
I see about 2V peak-to-peak on the scope!
I am expecting it leads to spurious reset/poweroff detections.
It might be helpful to add a filter on the AT91 side for RST and VCC.
Maye an R/C filter that can be enabled by an I/O pin using 0/HI-Z switching?
Another idea is to do enable the internal AT91 pin pullups.
Just loading RST and VCC a bit might be enough.
( Another alternative is to filter RST and VCC measurements in
software. I tried this but results are not very meaningful at this
point.. )
Cheers,
Tom