Thonny interpreter for stm32f407 ?

[stuarte83]

I have checked the drop down list in Thonny/Tools/Options/Interpreter and it does not list a micropython interpreter for stm32f407.

So, is there an interpreter for the stm32f407 discovery board ?

[bikeNomad]

Use MicroPython (generic), and flash your board with the STM32F4DISC firmware: https://micropython.org/download/STM32F4DISC/

[stuarte83]

Good afternoon Mr Konz, Thank you for your reply.Sadly, this does not seem to be working. Please see attached screenshot. I believe(!) that I have flashed STM32F4DISC-20250911-v1.26.1.hex using STLink tool. The LED on the board's top left named COM sometimes always displays red and sometimes it flashes from red to green. Pressing the board's black reset button does not cause either Thonny to recognise the board or to cause the COM LED to change from always displaying red. Tomorrow I am going to install Debian 13 Trixie in the hope that this will ease at least some of my problems. Thank you again for your help. Stuart

…

On Sun, 12 Oct 2025 at 19:04, Ned Konz ***@***.***> wrote: Use MicroPython (generic), and flash your board with the STM32F4DISC firmware: https://micropython.org/download/STM32F4DISC/ — Reply to this email directly, view it on GitHub <#18235 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ARPH3RXXE6JXT4U2GFRLBHL3XKJ2LAVCNFSM6AAAAACI5LQLK6VHI2DSMVQWIX3LMV43URDJONRXK43TNFXW4Q3PNVWWK3TUHMYTINRVHE3TAOI> . You are receiving this because you authored the thread.Message ID: ***@***.*** com>

[GitHubsSilverBullet]

The LED on the board's top left named COM sometimes always displays red and sometimes it flashes from red to green.

Just connecting CN5 to the system, mine does always blink LD1/COM (0.5Hz) in red. Though I haven't connected anything to CN1.

After connecting, it takes roughly half a second for the ttyACM0 to show up.
Another second for the FLASH drive.

[23424.665243] usb 1-1.3.3: new full-speed USB device number 13 using ehci-pci
[23424.780119] usb 1-1.3.3: New USB device found, idVendor=f055, idProduct=9800, bcdDevice= 2.00
[23424.780124] usb 1-1.3.3: New USB device strings: Mfr=1, Product=2, SerialNumber=3
[23424.780126] usb 1-1.3.3: Product: Pyboard Virtual Comm Port in FS Mode
[23424.780127] usb 1-1.3.3: Manufacturer: MicroPython
[23424.780129] usb 1-1.3.3: SerialNumber: xxxxxxxxxxxx
[23424.781262] usb-storage 1-1.3.3:1.0: USB Mass Storage device detected
[23424.782227] scsi host6: usb-storage 1-1.3.3:1.0
[23424.782401] cdc_acm 1-1.3.3:1.1: ttyACM0: USB ACM device
[23425.790001] scsi 6:0:0:0: Direct-Access     MicroPy  pyboard Flash    1.00 PQ: 0 ANSI: 2
[23425.790332] sd 6:0:0:0: Attached scsi generic sg5 type 0
[23425.791328] sd 6:0:0:0: [sdf] 480 512-byte logical blocks: (246 kB/240 KiB)
[23425.791946] sd 6:0:0:0: [sdf] Write Protect is off
[23425.791950] sd 6:0:0:0: [sdf] Mode Sense: 03 00 00 00
[23425.792572] sd 6:0:0:0: [sdf] No Caching mode page found
[23425.792578] sd 6:0:0:0: [sdf] Assuming drive cache: write through
[23425.811985]  sdf: sdf1
[23425.831717] sd 6:0:0:0: [sdf] Attached SCSI removable disk
$ ls -la /media/PYBFLASH
drwxr-xr-x   2 ······· ······· 16384  1. Jan 1970  .
drwx------+ 17 ······· ·······  4096 13. Okt 14:47 ..
-rw-r--r--   1 ······· ·······   454 31. Dez 2014  boot.py
-rw-r--r--   1 ······· ·······    34 31. Dez 2014  main.py
-rw-r--r--   1 ······· ·······  2597 31. Dez 2014  pybcdc.inf
-rw-r--r--   1 ······· ·······   526 31. Dez 2014  README.txt
$ 

[stuarte83]

Good morning @GitHubSilverBullet,

Thank you for your reply. ttyACM0 never appeared in /dev of Debian 12 bookworm. I spent part of yesterday upgrading the laptop to Debian 13.1 Trixie. Just spent the last couple of hours getting the system usable again as well as installing various packages. Just had a look in Trixie's /dev. No ttyACM0, this with the stm32 board connected. Ho hum... the adventure continues :-)

[GitHubsSilverBullet]

Unplug the Disco.
Start a terminal, login as root.
dmesg -w will display the last couple of system messages and wait for new ones.
Plug Disco in.
Check system messages.
All that runs fine on Debian 11,12,13.
It also might be a good idea to try a different USB port (hub and PC directly)

[shariltumin]

I don't know what computer you're using. You can try connecting to the board using a serial terminal. On Linux, you can try tio or minicom, for example. Even better, install mpremote on your PC and use it to connect to your board.

https://docs.micropython.org/en/latest/reference/mpremote.html

If your board was flashed with the correct firmware (STM32F4DISC seems to be the right choice), you will get the REPL. You don't need Thonny to interact with or program your board.

[robert-hh]

So @stuarte83 could do the same test. If the same behaviour happens, then MicroPython is active and there is a problem with the USB link, cable, plugs, ....

[stuarte83]

@robert-hh ,
JP1 always on, CN3 both jumpers off when flashing and on otherwise.

@GitHubsSilverBullet
Re button pushing: Same behaviour as you state above. So, it is definitely the cable that is the problem. Rats, I don't have another cable with micro-usb connector.

[stuarte83]

Hi all,

Well, time to head home now where I don't have net access. Thank you all very much for all your help for this undoubted noob. I will see if I can find another type A to micro-usb cable. Might be back on tomorrow. Thanks again.

Stuart

[stuarte83]

Good morning all,

You are never going to believe this, but... I seem to have fixed my stm32-board/tty problem.

The last line of dmesg complained that:-

[ 115.872077] warning: `kdeconnectd' uses wireless extensions which will stop working for Wi-Fi 7 hardware; use nl80211

So I installed package iw which is based on nl80211 interface. I connected only(!) an alternate micro-usb cable to CN5. The board did not power up (no green or red leds) and so no entry for ttyACMs or ttyUSBs showed in /dev.
Then, on a whim, I also installed iwd, network-manager-iwd, and python3-pyric packages. I then connected previously-used mini-usb cable to CN1. Suddenly, leds (green and red) lit up on the board and a notification popped up out of the notification area mentioning PYBFLASH. Checking in /dev I now(!) find an entry for ttyACM0. Checking in Dolphin, I found a new entry under Devices labelled PYBFLASH which displays icons for the files on the board. So now I should have access to those files using whatever software tool of choice.

The down side of this success is that wlp7s0 has been deauthenticated as listed by dmesg.

[ 979.887357] wlp7s0: deauthenticating from 34:3a:20:de:c2:80 by local choice (Reason: 3=DEAUTH_LEAVING)

This happened after installing the three packages listed above. It means that my laptop can no longer access the internet. So, how do I now re-authenticate wlp7s0 ?
(This message is coming from a public pc in my local library)

[robert-hh]

I cannot believe that the network stuff is related to serial USB, at least not to show up /dev/ttyACMx. What I found in the STM board manuals is, that the board is powered by CN1. So just attaching CN1 and CN5 with proper cables should be sufficient.
There is however a modem manager, which tries to capture /dev/ttyACMx, if present.

[stuarte83]

Good morning @robert-hh,

Hey, don't ask me ! I'm just a tourist here ! :-) Seriously though, maybe Trixie just needed the complete iw stack in order to find usb-connected external devices.

So just attaching CN1 and CN5 with proper cables should be sufficient.
Yes, that's what I ended up with when that notification popped up.

There is however a modem manager, which tries to capture /dev/ttyACMx, if present.
And that would be (cutecom, minicom, tio, other) ?

[GitHubsSilverBullet]

I cannot believe that the network stuff is related to serial USB, at least not to show up /dev/ttyACMx.

It isn't. It's just a coincidence (when doing two independent things at the same time)
As you stated, the board needs power (through CN1) AND the CN5 connection.
Or – that's what I do here – bridge PA9 to +5V on the same row of the P2 connector and use ONLY CN5.