The bootloader checks the CRC of the application code and passes control to the application code it matches a saved value. If it doesn't match, it waits for commands from the host system to update the application firmware. The application will clear...

I'm using an STM32L486 as my master and as the slave. My issue is the slave transceiver I want to use pulls the RO (RX on the STM32) pin down after receipt of a message. The RTOI doesn't fire until the RX pin goes high from the next message.