16.8.2.2.2 Workflow

  1. Enable global interrupts, so that the callbacks can be fired. 
    system_interrupt_enable_global();
  2. Send a string to the USART to show the demo is running, blocking until all characters have been sent. 
    uint8_t string[] = "Hello World!\r\n";
usart_write_buffer_wait(&usart_instance, string, sizeof(string));
  3. Enter an infinite loop to continuously echo received values on the USART. 
    while (true) {
  4. Perform an asynchronous read of the USART, which will fire the registered callback when characters are received. 
    usart_read_buffer_job(&usart_instance,
        (uint8_t *)rx_buffer, MAX_RX_BUFFER_LENGTH);