STM32F205 Bootloader does not work

[blabla]

Posted on April 15, 2015 at 15:46

Hello everybody,

I am working with a STM32F205 and I want to use the bootloader over USART1 with a FTDI231X. BOOT0 and RST are controlled by the FTDI correctly, BOOT1 is pulled to GND and the other bootloader interfaces are pulled to VDD. But still the STM does not respond on the 0x7F command. Does anyone has an idea what the problem could be? #bootloader #stm32f2

[Tesla DeLorean]

Posted on April 15, 2015 at 18:06

Don't know. Stick it on a logic analyzer, and confirm you're sending the 0x7E at 9600 8E1 (Even Parity)

The NRST needs to use an Open-Drain, driven low, pulled High, driving it High/Low with a Push-Pull driver will cause the part/reset to fail.Perhaps the part is entirely non-functional, does JTAG/SWD work?Do you have the analogue supply connected?What's the state of the NRST pin? High/Low when observed.Voltages on the VCAP pins?

[blabla]

Posted on April 16, 2015 at 18:00 The problem was, that the uC needs over 90ms after reset to recognize the 0x7F command. Thanks for your help!