The Kinetis MCU bootloader current supports auto baud rate max is 230400. How to modify to support the baud rate more than 230400 like 460800 or 921600?
Bootloader doesn't restrict UART speed. Since Kinetis MCU UART module don’t have auto frequency detect function, the bootloader detects frequcny by software. It uses GPIO interrupt and timer to measure frequency. If the code can get the baudrate precisely, speed higher than 230400 should be fine. If it can't, you can appoint the baudrate in
bool scuart_poll_for_activity(const peripheral_descriptor_t *self)
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