Hello,
we use STM32F413RGT6 as slave board communicate through rs485 bus. In application, we drive rts by emulated gpio. We use for update of the board HW uart bootloader. Due to weakness of the HW bootloader we face some problems during update on half duplex uart, because HW bootloader sometimes response sooner, than is complete msg send. Due to it we receive damaged ack, for example 0xb9 instead of correct 0x79.
Next challenge was activate uart HW bootloader, because STM logic is, that first activity on any digital bus lead to choose that bus as update bus, so we must rework our application to have stable start until we start to communicate on update uart (rs485) bus. This could be improved forexample by HW boot pins...
Last thing, what i can say as improvement could be better specification in an2606-stm32-microcontroller-system-memory-boot-mode-stmicroelectronics.
Because if you want to jump from bootloader to the application, you must send sequence init, GO command and jump to address and after ack must wait for example 1 sec before send another command, otherwise it hang in bootloader even bootloader send you ack. Nothing about it is written in that document.
