mpremote gives UnicodeError on ARDUINO_OPTA V26, V27, V28
Port, board and/or hardware
ARDUINO_OPTA
MicroPython version
MicroPython v1.26.1 on 2025-09-11; Arduino OPTA with STM32H747
I do not have the WIFI version but the simplest without WIFI and RS485. Might this be the problem?
The same on V27 (latest) and V28 (preview).
py.exe -m mpremote connect COM9 fs tree
tree :
:/flash
mpremote: Error with transport:
Traceback (most recent call last):
File "<stdin>", line 2, in <module>
UnicodeError:
It's not possible to upload any file or use any filesystem function of mpremote.
mpremote repl works!
Using mpremote 1.27.0 on Windows with Python 3.14.2.
Thank you
Best greetings
Thomas
Reproduction
Connect OPTA and run mpremote.
py.exe -m mpremote connect COM9 fs tree
tree :
:/flash
mpremote: Error with transport:
Traceback (most recent call last):
File "<stdin>", line 2, in <module>
UnicodeError:
Expected behaviour
The command should give a similar output to the following;
py.exe -m mpremote connect COM10 fs tree
tree :
:/flash
├── BOOTEX.LOG
├── FOUND.000
│ ├── FILE0000.CHK
│ ├── FILE0001.CHK
│ ├── FILE0002.CHK
│ ├── FILE0003.CHK
│ └── FILE0004.CHK
├── README.txt
├── System Volume Information
│ ├── IndexerVolumeGuid
│ └── WPSettings.dat
├── _mqtt_test_pybd.txt
├── boot.py
Observed behaviour
mpremote ends with the error message "UnicodeError":
py.exe -m mpremote connect COM9 fs tree
tree :
:/flash
mpremote: Error with transport:
Traceback (most recent call last):
File "<stdin>", line 2, in <module>
UnicodeError:
Additional Information
No, I've provided everything above.
Code of Conduct
Yes, I agree
mpremote cannot cat with recent MP on pyboard
Port, board and/or hardware
pyboard
MicroPython version
MicroPython v1.24.0-preview.36.gd7d77d91b on 2024-06-12; PYBv1.1 with STM32F405RG
Reproduction
mpremote cat main.py
Expected behaviour
List the content of main.py.
Observed behaviour
Traceback (most recent call last):
File "<stdin>", line 3, in <module>
UnicodeError:
Additional Information
This error is also observed with MP version 1.22.2 .
Perhaps it is related to this error message (RuntimeError below) at boot up ? :
mpremote
Connected to MicroPython at /dev/ttyACM0
Use Ctrl-] or Ctrl-x to exit this shell
RuntimeError: name too long
MicroPython v1.24.0-preview.36.gd7d77d91b on 2024-06-12; PYBv1.1 with STM32F405RG
Type "help()" for more information.
>>>
Code of Conduct
Yes, I agree