Hi Kevin,
you are right, the GPIO of the SAM3S are 3.3V only,
and are not 5V tolerant.
[...]
and would not recommend using it with 5V.
Thank you for confirming my observations.
If you don't want to create a board, you could
just use a SIMtrace board
and desolder the MCU (e.g. using hot air).
Uhmm, I would rather not mutilate an otherwise perfectly good SIMtrace
board that is still usable for debugging lower-voltage phones. For
the purpose of sniffing high-voltage SIM communication, I'll make my
own little adapter PCB with just a SIMtrace-mimicking FPC connector, a
SIM socket and some header pins - trivial really, I just need to get
around and do it. I am not in any hurry, so I will get to it when I
get to it, and then wait for the PCB fab...
M~