Hello Has anyone a working template for UNO R4 with Rust? I tried it, but I will be not built correctly. The Arduino blinks always in the same frequency. Independent from the delay I programm. An empty program with a simple does not stop blinking. #![no_std] #![no_main] use arduino_uno_r4_hal::gp…

This helps running "probe-rs run --chip R7FA4M1AB".

hi @ora8 welcome to the forum. [image] ora8: An empty program with a simple does not stop blinking. Are you sure you are actually uploading? Have you tried the regular blink code and changed it so you can be sure? a7

I think so, I get the messages: Compiling arduino_rust_app v0.1.0 (C:\arduino_rust_app) Finished `release` profile [optimized] target(s) in 0.30s C:\arduino_rust_app>arm-none-eabi-objcopy -O binary target\thumbv7em-none-eabihf\release\arduino_rust_app imap imp image.bin C:\arduino_rust_app>…

The Arduino IDE uses objcopy -O binary -j .text -j .data Perhaps you're failing to copy some of the image to the .bin file?

Thank You, I have changed it, but no success.

It works on R4 wifi only, not on R4 minima. Has it to do that the R4 wifi has a integrated debugger? For R4 minima I still looking for a solution.

[image] ora8: Has it to do that the R4 wifi has a integrated debugger? Ah. Are you linking in a way that accounts for the bootloader? According to the boards.txt, minima uploads to 0x10000, and Wifi doesn't. I'm not sure of the details.

Now I have the issue that on R4 Wifi probe-rs works but the Arduino does not find the device. "C:\Users\ora8\AppData\Local\Arduino15\packages\arduino\tools\bossac\1.9.1-arduino5/bossac" -d --port=COM10 -U -e -w "C:\Users\ora8\AppData\Local\arduino\sketches\C9099938545AB13C957F3A54FD1CC74A/Blink.ino…

I get still get the error No device found on COM3 Fehlgeschlagenes Hochladen: Hochladefehler: exit status I have reflashed the bootloader with no success. Double clicking the reset button does not fadein fadein the builtin led. The old program is still running. Any advices?

I found the problem is the Rust programm overrides the Arduino Bootloader. I must manually reinstall it.

Yeah arduino-uno-r4-hal is a vibe coded mess. It's clobbering the OSM and the bootloader both of which should be resolved by reinstalling the bootloader. You can reinstall the bootloader with probe-rs, and I think the next version of probe-rs should handle autodetection so you won't need to manual…

Rust and Arduino UNO R4

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ora8 March 8, 2026, 7:50pm 17

Cool you are the author. I show what I can do. I am not a STM32 fanboy. I have a discovery board for testing. But what I am prefer is Arduino or xmc4xx.

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Rust and Arduino UNO R4

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