stm32mp157 (discovery kit) usart3 not starting from A7
I am using stm32mp157d from stm32mp1 dk1 to work on an embedded project. When I boot bare-metal from A7, I have no trouble to read and write to UART 4, however I run into a wall when I try to user UART 7 or USART3. The HAL library works for UART4, so...