STM32CubeProgrammer-- BootLoader- USART RS485

[ControlFreak]

Hello,

I am using STM32CubeProgrammer for Bootloading for updating Firmware.

I am bootloading over USART using RS232 Protocol. I am under the impress that unlike Flash Loader Demo GUI, STM32Cubeprogrammer can boot load in RS485 Protocol. Can some one please confirm? Also can some guide me on how should my transreceiver be configured (I mean in bootloading whether my transreceiver should configured as Transmitter or receiver )?

[Tesla DeLorean]

Hard to say if it is going to work. I would expect the STM32 wants to see a Receiver, as it is looking for signals on a number of pins to determine which is active, and timing USART RX pins to figure the baud rate from the 0x7F 8E1 bit pattern.

[ControlFreak]

Thanks for prompt reply. But it is know to work for RS485? Beacuse When I set it as Receiver I am getting error for checking my Boot configuration and serial port configuration. But this piece of code works fine(I am still testing it hard enough to make sure it never breaks) for RS232 protocol.

[Tesla DeLorean]

I don't think the System Loader is built for a half-duplex connection, you really should write your own loader with more situational awareness about your specific board and interfaces, and the expectations those have.

The System Loader is sensitive to glitches on watched pins, and the baud measurement is a one-shot deal, so you need to build something that can be readily reset and retried.

[ControlFreak]

Hi Clive, Just one clarification needed. By System loader, you dont mean Flash loader or STM32Cubeprogrammer? But it means built in bootlaoder code in system memory.

[Tesla DeLorean]

I mean the ROM/OTP loader delivered with the chip, and described in AN2606

[ControlFreak]

Thanks