firmware

Debugging

Firs of all read The Embedded Rust Book/Hardware!

Will debug with the help of ST-Link included into STM32F0DISCOVERY evaluation board. To program and debug stm32f042f4p6 with this board remove the 2 jumpers from CN2 (see en.DM00050135.pdf, page 16):

STM32F0DISCOVERY CN3/SWD connector	STM32F042F4P6
1 - VDD_TARGET - VDD from target MCU	16 - VDD and 5 - VDDA
2 - SWCLK - SWD clock	20 - PA14
3 - GND - Ground	15 - GND
4 - SWDIO - SWD data input/output	19 - PA13
5 - NRST - RESET of target MCU	4 - NRST
6 - SWO - Reserved	NC

1. Add udev rule for the STMicroelectronics ST-LINK/V2:

$ sudo vim /etc/udev/rules.d/99-stlink.rules

-------
ATTRS{idVendor}=="0483", ATTRS{idProduct}=="3748", MODE="0666"
-------

$ sudo udevadm trigger

1. Build project with one of the following commands:

$ cargo build
$ cargo build --target=thumbv6m-none-eabi
$ cargo build --target=thumbv6m-none-eabi --release
$ cargo +nightly build --target=thumbv6m-none-eabi --release --features nightly

2. Run openocd -f openocd.cfg
3. In another terminal run arm-none-eabi-gdb -x openocd.gdb target/thumbv6m-none-eabi/release/kroneum-bin

Firmware Upload via USB DFU

| Micro USB | STM32F042F4P6 | | ------------------------------------:| | 1 - VBUS + | NC | | 2 - DATA - | 09 - PA11 - USB DM | | 3 - DATA + | 10 - PA12 - USB DP | | 4 - ID | NC | | 5 - GND | 15 - GND |

Pin 1 (PB8-BOOT0) should be connected to VDD\VDDA (+3.3V).

Also make sure you read documentation for cargo-binutils and dfu-util.

1. Build binary with:

$ cargo build --release -p kroneum-bin
$ $(find $(rustc --print sysroot) -name llvm-objcopy) ./target/thumbv6m-none-eabi/release/kroneum-bin -O binary ./target/fw-upload.bin
Or call the following command from the `./bin` subfolder
$ cargo objcopy --bin kroneum-bin --release -- -O binary ../target/fw-upload.bin

2. Upload binary with:

$ dfu-util -a 0 -d 0483:df11 -s 0x08000000:leave -D ./target/fw-upload.bin

3. Backup binary with:

$ dfu-util -U fw-from-device.bin -a 0 -d 0483:df11

Notes

1. Steps 1-3 above can be replaced with just $ ./scripts/flash.sh.

2. If binary is too large GDB may fail so try to use --release flag with cargo build.

3. To reload program on the MCU use monitor reset halt

4. RTC & Low Power modes: https://github.com/mattico/stm32f0-Discovery_Tools/blob/master/ST_Example_Projects/Projects/Peripheral_Examples/PWR_CurrentConsumption/stm32f0xx_lp_modes.c

Useful links

1. The Embedded Rust Book
2. Firmware for Anne Pro Keyboard written in Rust
3. USB HID device development on STM32 F042
4. A development board for the STM32F042 TSSOP package and schematics
5. STM32F042 Breakout
6. Tim's Open Micro USB
7. Online Circuit Simulator
8. ifUSB repo and USB multi protocol interface tool