Start USART Bootloader on STM32F070 device does not work

Posted on May 22, 2016 at 10:50

Hi all,

i am using a Nucleo board ''NUCLEO F070RB'' and i want to start the UART Bootloader. Unfortunately the bootloader doesn�t send the Ack  byte (0x79) after activation.

My procedure to start the bootloader:

- connect the boot0 pin to 3V3

- reset the board (black botton)

- send the 0x7F Byte with 9600, even parity, 1 start bit, 1 stop bit

=> at this point i expect to receive the 0x79 ACK byte from the micro

What i did till now to find what i am doing wrong:

- i checked that nBOOT1 bit in the option bytes is set to 1

- due to the fact that the F070 device has an USB interface i removed the crystal (and i opened SB50 from the NUCLEO to avoid getting clock from the debugger)

- i am quite sure that the micro is in bootloader mode, because the application doesn�t start.

- i verified my sequence with a NUCLEO-F030RB

=> here erverything works fine. The problem just excists on the F070.

=> all my HW-connections should be ok (same Pins)

I am running out of ideas :( 

Any help is appreciated.

Thanks

Thomas

#nucleo-f070rb #bootloader