Every STM32 family with a Cube HAL (C0, F0–F7, G0, G4, H5, H7, L0–L5, U5, WB, WL). Path A flashes a ready firmware on popular boards; path B puts MicroCS into your own STM32CubeMX / CubeIDE project so every peripheral you configured there is usable from C#.

1. Download the file for your board from the latest release: nucleo_f401re, nucleo_f411re, nucleo_f446re, nucleo_g474re, nucleo_l476rg, nucleo_h743zi or blackpill_f411ce (.bin).

2. Nucleo: plug in the ST-LINK USB and copy the .bin onto the NOD_… drive. The board restarts with MicroCS. Black Pill: hold BOOT0, tap NRST, release BOOT0, then dfu-util -a 0 -s 0x08000000:leave -D microcs-<version>-blackpill_f411ce.bin; wire a 3.3 V USB-serial adapter to PA9 (TX) / PA10 (RX) for the console.

3. Open the ST-LINK virtual COM port (or the adapter) at 115200 baud, or MicroCS Studio → Connect, and press Enter:

   > var led = new Pin("LED", GPIO.Output);
   > led.Toggle();
   > Console.WriteLine(string.Join(",", I2C.Scan(1)));   // Nucleo: SCL = D15 (PB8), SDA = D14 (PB9)
   

Which pins and peripherals the ready firmware wires up: firmware/README.md.

• a USART for the console (115200 8N1) with its global interrupt — on Nucleo-64 boards USART2 (PA2/PA3) is the ST-LINK virtual COM port;
• whatever C# should use: I²C, SPI, ADC, TIM channels in PWM mode, a basic TIM with its update interrupt (for Timer), DAC, I²S, QUADSPI/OCTOSPI, CAN/FDCAN, IWDG, RTC;
• EXTI interrupts for the pins you want GPIO.OnChange on;
• heap/stack: MicroCS gets its heap as a static array (64 KB in the example); give the main stack at least 8 KB (Project Manager → Linker settings → Minimum stack size).

Generate the code.

Copy (or git submodule add) MicroCS into the project, e.g. Middlewares/MicroCS, then

• CubeIDE (Eclipse): right-click the project → Properties → C/C++ General → Paths and Symbols: add the source folders src, modules, ports/stm32 and the include paths include, ports/stm32. Add the symbol MCS_ENABLE_TINYFS=1 to keep files in the flash.
• CMake (CubeMX 6.11+ / VS Code): in CMakeLists.txt

  set(MICROCS_PORT stm32)
  set(MICROCS_FS tinyfs)                 # files in the chip's flash, nothing to download
  add_subdirectory(Middlewares/MicroCS)
  target_link_libraries(${CMAKE_PROJECT_NAME} microcs)

• Makefile projects: include Middlewares/MicroCS/microcs.mk.

Copy example_main.c to Core/Src/microcs_main.c, change the handle names (huart2, hi2c1, hspi1, hadc1, htim3, …) and board.name, and call it from main.c:

/* USER CODE BEGIN 2 */
extern void microcs_main(void);
microcs_main();          /* never returns */
/* USER CODE END 2 */

The bus numbers in C# are the peripheral numbers: board.i2c[1] = &hi2c1 → I2C.Open(1), board.uart[2] = &huart2 → UART.Open(2, …), board.pwm[0] = { &htim3, TIM_CHANNEL_1 } → PWM.Set(0, …). Full list: ports/stm32/README.md.

Build, flash (Run/Debug in CubeIDE, or copy the .bin to the ST-LINK drive), open the virtual COM port at 115200 and press Enter.

python3 tools/mcs_remote.py --port COM7 put blink.cs /main.cs + run /main.cs

or MicroCS Studio → Save & Run. /main.cs runs at every start.

More: ports/stm32/README.md (every peripheral, interrupts, flash files, memory per part).