Today I decided to test NuttX on “FEZ Cerbuino Bee Rev 1.3”. Because this board uses the STM32F405RG chip I started adapting the olimex-stm32-h405 board config.
At configs/olimex-stm32-h405/include/board.h modified the crystal (XTAL) from 8MHz to 12MHz:
#define STM32_BOARD_XTAL 12000000ul
Unfortunately it didn’t work. The usbnsh was not starting.
Then I decided to test other board config, I selected mikroe-stm32f4 this time and just modified the XTAL config from 8MHz to 12MHz and flashed it using dfu-util (to enter on DFU mode just hold the LDR button and plug the USB cable (X4 connector) to computer) :
$ sudo dfu-util -d 0483:df11 -a 0 -s 0x08000000 -D nuttx.bin
This time usbnsh configuration worked fine and I got “nsh>” prompt from USB (/dev/ttyACM0).