[Nucleo-F767ZI] USB Mass storage does not show in Win10

[gdjsky01]

I am running MicroPython v1.17 on 2021-09-02; NUCLEO-F767ZI Rev B-01

I never, ever figured out a way to place the board in the DFU bootloader, and I have tried everything I can find including reading RTFM'ing. However I was able to convert the DFU to Hex and use ST-LINK util to load the hex file on the board.

I have a REPL prompt! I can interact with the board (turn on and off things) from the REPL. However nothing I have tried causes the board to act as a flash drive visible to Windows 10. I checked the device manager and it says there are VCP, ST-LINK, and Mass Storage Interfaces. I am using the latest WinUSB 6.x driver. It shows as a COM port. Nothing in explorer or command.

On my MAC (Big Sur) again I can interact with the repl, AND the board shows up as /Volume/NODE_F767ZI however that mount exhibits none of the expected behavior. No main.py shows, no boot.py, etc. Just the usual MBED.HTM

I have surfed for like 48 hours and can't find where I went wrong (other than I have never ever figured out how to get the board into a DFU bootloader - and I have jumped BOOT0 to VCC and tried with and without NUCLEO jumpers). I am SOOOOO close. I hope I have provided enough details. And thank you for reading.

Best wishes

[gdjsky01]

Nothing? More information needed? Crickets?

[dhylands]

Which USB port are you using?

The end nearest the network connector (CN13) is the one that the DFU bootloader would show up on. The other one (CN1) is connected to the stlink debugger. It should also show a file system, but it's designed for flashing, and isn't visible to micropython.

The stlink debugger has a serial pass-thru mode where it's USB connection will show up on a serial port connected to the F767, but CN13 is the USB port that's connected directly to the F767.

The docs say that CN13 is insufficient to power the board, so you'll need to have both USB connectors plugged in.