• USART2 Interrupt occur just one time or too late or never. (stm32f10 Keil) 

    Hello there. I have a homework to do stopwatch, but I'm having a few problems. 
    In code there are 4 button interrupt(B0-B3), 1 timer1 interrupt for 1 ms and USART2 interrupt. 
    Buttons and timer interrupts work properly but USART2 interrupt work just…