Port, board and/or hardware

STM32 port on a NUCLEO-144--F767ZI

MicroPython version

MicroPython v1.27.0-preview.440.ga6864109db on 2025-11-23; NUCLEO-F767ZI with STM32F767

Reproduction

0. (Optional) Perform a mass erase on all flash blocks.
1. Build main firmware and mboot, then upload image to the board with deploy-stlink
2. Reboot the board
3. Run mpremote mip install unittest
4. Wait until it hangs

Expected behaviour

mpremote mip should install the required package

Observed behaviour

The upload process hangs at random intervals, and when stopping it via CTRL+C the traceback is as follows (the process was stopped after a few minutes of being stuck at 13%):

Traceback (most recent call last):
  File "/home/agatti/src/micropython/ports/stm32/../../tools/mpremote/mpremote.py", line 6, in <module>
    sys.exit(main.main())
             ~~~~~~~~~^^
  File "/home/agatti/src/micropython/tools/mpremote/mpremote/main.py", line 614, in main
    handler_func(state, args)
    ~~~~~~~~~~~~^^^^^^^^^^^^^
  File "/home/agatti/src/micropython/tools/mpremote/mpremote/mip.py", line 206, in do_mip
    _install_package(
    ~~~~~~~~~~~~~~~~^
        state.transport,
        ^^^^^^^^^^^^^^^^
    ...<4 lines>...
        args.mpy,
        ^^^^^^^^^
    )
    ^
  File "/home/agatti/src/micropython/tools/mpremote/mpremote/mip.py", line 169, in _install_package
    _install_json(transport, package, index, target, version, mpy)
    ~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/agatti/src/micropython/tools/mpremote/mpremote/mip.py", line 131, in _install_json
    _download_file(transport, file_url, fs_target_path)
    ~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/agatti/src/micropython/tools/mpremote/mpremote/mip.py", line 99, in _download_file
    transport.fs_writefile(dest, data, progress_callback=show_progress_bar)
    ~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/agatti/src/micropython/tools/mpremote/mpremote/transport.py", line 163, in fs_writefile
    self.exec("w(" + repr(chunk) + ")")
    ~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/agatti/src/micropython/tools/mpremote/mpremote/transport_serial.py", line 309, in exec
    ret, ret_err = self.exec_raw(command, data_consumer=data_consumer)
                   ~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/home/agatti/src/micropython/tools/mpremote/mpremote/transport_serial.py", line 295, in exec_raw
    self.exec_raw_no_follow(command)
    ~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^
  File "/home/agatti/src/micropython/tools/mpremote/mpremote/transport_serial.py", line 273, in exec_raw_no_follow
    return self.raw_paste_write(command_bytes)
           ~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^
  File "/home/agatti/src/micropython/tools/mpremote/mpremote/transport_serial.py", line 228, in raw_paste_write
    data = self.serial.read(1)
  File "/usr/lib/python3.13/site-packages/serial/serialposix.py", line 565, in read
    ready, _, _ = select.select([self.fd, self.pipe_abort_read_r], [], [], timeout.time_left())
                  ~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
KeyboardInterrupt

The firmware is still waiting for data to arrive on the serial port when mpremote seems to be stuck:

^C
Program received signal SIGINT, Interrupt.
mp_hal_stdin_rx_chr () at mphalport.c:53
53          for (;;) {
08:14:08 mp_hal_stdin_rx_chr > bt
#0  mp_hal_stdin_rx_chr () at mphalport.c:53
#1  0x08068aec in mp_reader_stdin_readbyte (data=0x2007ff74)
    at ../../shared/runtime/pyexec.c:255
#2  0x08023164 in next_char (lex=lex@entry=0x20037b50) at ../../py/lexer.c:174
#3  0x08023456 in parse_string_literal (lex=0x20037b50, is_raw=false, 
    is_fstring=false) at ../../py/lexer.c:413
#4  mp_lexer_to_next (lex=lex@entry=0x20037b50) at ../../py/lexer.c:696
#5  0x0802443c in mp_parse (lex=lex@entry=0x20037b50, 
    input_kind=input_kind@entry=MP_PARSE_FILE_INPUT) at ../../py/parse.c:1167
#6  0x08068be8 in parse_compile_execute (source=source@entry=0x2007ff7c, 
    input_kind=input_kind@entry=MP_PARSE_FILE_INPUT, 
    exec_flags=exec_flags@entry=65) at ../../shared/runtime/pyexec.c:111
#7  0x08068d90 in do_reader_stdin (c=65) at ../../shared/runtime/pyexec.c:324
#8  pyexec_raw_repl () at ../../shared/runtime/pyexec.c:567
#9  0x080730d4 in stm32_main (reset_mode=<optimized out>) at main.c:718
#10 <signal handler called>

in fact, reconnecting to the serial port will find the interpreter still waiting for data to arrive.

Additional Information

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Code of Conduct

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