I'm learning micro controller using STM32F429I-DISCOVERY board and have a question about non-blocking mode UART reception.
I compiled this example project(UART_TwoBoards_ComIT) and flashed the STM32 board with the binary file. Then I connected the UART1 pins on the STM32 board to Beaglebone Black's UART1 pins. The Beaglebone Black board uses Debian linux and a serial monitor 'minicom' so that it can communicate with the STM32 board via UART.
Then I could see " ****UART_TwoBoards_ComIT**** ****UART_TwoBoards_ComIT**** ****UART_TwoBoards_ComIT****" from the serial monitor. Up to here everything looked fine. But when I type a random letter in my serial monitor, I can't see that LED3 is toggled. I checked that the TX pin of the Beaglebone Black outputs digital signals at that time. I guess that the STM32 board doesn't receive any data from the Beaglebone Black board and enters to infinite loop, but I'm not confident..
Could you please explain why the LED3 is not toggled, even if my Beaglebone Black sends data to the STM32 board?