FK750M3

FK750M3 board definition for Micropython. Now it supports mboot.

Build steps:

• Go to the ports/stm32 directory
• Go to the mboot subdir
• Run make BOARD=FK750M3
• Connect the board to the PC using ST-Link
• Flash the firmware.hex or firmware.bin from the subdir build-FK750M3 using a favorite flashig app (e.g. STM32CubeProgrammer)
• Disconnect the ST-Link device
• Go back to the ports/stm32 directory
• Run make BOARD=FK750M3
• Connect the board to the PC using USB
• Press and hold the user button, press the resset button and release the user button
• Flash the firmware.dfu from the subdir build-FK750M3 using any DFU flashing application, e.g. dfu-util -D firmware.dfu
• Reset the board

The configuration is far from complete, it serves as a guide for creating custom Micropython board definitions.