I'm currently trying to port Espruino to the GHI Electronics FEZ CERB 40 board which is using a STM32F4. So I took the STM32F4DISCOVERY board configuration and compiled and flashed it to the board using the dfu-util. After I connected a serial line I have seen garbage on the terminal. It looks like I have a timing issue on my serial line so my current guess is that the PLL is not set up as expected. I looked closer to the schematics of the CERB40 and the STM32F4DISCOVERY and spotted that they are using a different system crystal. CERB40 uses 12 MHz instead of 8 MHz on the DISCOVERY. So I looked in the source and found the PLL_M define in targetlibs/stm32f4/lib/system_stm32f4xx.c and changed it from 8 to 12 to get to the 168 MHz. So after a make clean and a recompile and flash I still get the garbage on the serial line. Can anybody give me a pointer what I might be missing here?
Thanks in advance,
© Espruino, powered by microcosm.
Report a problem