Does anybody has a clue about the HW revisions, how they are labeled on PCB and where to get the related schematics?
Story
I have my project. It is a FULL OPEN SOURCE project via STM32CubeIDE (not using any Arduino IDE, LIB, FW etc. - not usable for me).
Project is here:
Portenta H7 Cube32IDE project - FULL OPEN SOURCE
I have 3 boards: I have used one of them and ALL FINE. All works.
Afterwards, I tried to flash and run the same FW on 2 other boards:
The USB UART (via USB-C as VCP) is not working!
After spending one day to check, debug ... my project source code - I have checked finally if I could find a HW revision label on the PCBs:
The TWO not working PCBs have a slightly different labeling at the back of PCB:
working PCB
2050 and ML-4R
failing PCBs (2x)
2014 and ML-2B
Is the ML-4R vs. ML-2B a HW revision number?
If so, where could I find the related schematics, at least a HW revision history or a remark in schematics?
Reason found
After studying different versions of schematics I could find on Internet, e.g. a rev. 1.0 vs. the Lite board schematics... I have seen this:
There is a RESETB signal on USB controller. This is driven as PJ4 from MCU. There seems to be a HW change, assuming: a pull-up was there which was later removed (even it was a pull-up and pull-down, holding signal in the "middle" but enough to release RESETB: now it needs PJ4 to be driven).
So, I had to initialize PJ4 and drive it (high) in order to release USB HS PHY from RESETB.
It is working now (after spending 24h to figure out by trial-and-error).
Conclusion
It seems to me: there are different HW revisions on the market for this Portenta H7 MCU module (board).
But Arduino does not publish revision numbers, a history, notifications about changes.
Even, to find the schematics is way to hard, almost impossible (often via other Internet sources). And at the end: you do not know which schematics version belongs to the board you have in hand and what are the "tiny" differences to make it working.
Request to Arduino team
Please, tell us if you have HW revision numbers on PCB boards.
If so, please provide a "revision history" for the changes, differences.
Please provide (publish) schematics but with a clear indication about revisions and modifications.
Thank you.