Bootloader programming using UART with STlink V2.1

[Roshan]

Hello guys,

I have a small question I have st link v2.1 which comes with the Nucleo board, so I need to program another custom board using this st link, but I have to do using UART (Rx, Tx) pins which is nearby the SWD connector, please if anyone has an idea about please let me know.

I used cube programmer and tried to connect with UART but it is giving an error that saying

Error: Activating device: KO. Please, verify the boot mode configuration and check the serial port configuration. Reset your device then try again...

Used the flash Loader as well but it is not connecting,

wiring was

Stlink Rx ---> MCU Tx (PA2)

Stlink Tx ----> MCU Rx (PA3)

BOOT0 --- High

NRST ----> NRST

If there is any other error can you point it to me?

[TDK]

Which nucleo board are you using to program? What chip/board are you trying to program?

Does the target board have power and have you put it into bootloader mode by toggling NRST while BOOT0 is active? Or powering up with BOOT0 held high?

[Roshan]

@TDK​ I have ST link V2.1 of Nucleo F412ZG and the target program custom board is L476RG, Yeah I have given power for the target one as well. I tried powering up with the BOOT0 high.

[TDK]

It should work in theory. Can you probe the lines to verify a signal exists and on the appropriate line? Also ensure settings are right. Note that bootloader requires even parity. Not real sure.