hwa/st/stm32/examples/05-1-uart/main.c

Use of the UART.

main.c

 
/*  This file is part of the HWA project.
 *  Copyright (c) 2021 Christophe Duparquet.
 *  All rights reserved. Read LICENSE.TXT for details.
 */
 
#include BOARD_H
 
#define AHBHZ           HW_DEVICE_HSIHZ         // AHB frequency
#define APBHZ           AHBHZ
 
#define UART            usart2
#define UART_TX         (porta,2)
 
 
int main ( )
{
  /*  Power the controllers we use
   */
  hw( power, (UART_TX,port), on );
  hw( power, UART, on );
 
  hw( configure, UART_TX, function, (UART,tx), mode, digital_output );
  
  hw( configure,        UART,
      mode,             uart,
      divider,          AHBHZ/10000,    // 10 kbps
      /* clockhz,               APBHZ, */
      /* bps,           100000, */
      /* tol,           0.01, */
      databits,         8,
      parity,           none,
      stopbits,         1,
      receiver,         off,
      transmitter,      on,
      run,              yes );
 
  for (;;) {
    while ( hw(read,(UART,txe)) != 1 ) {}
    hw_waste_cycles( 0.003*AHBHZ );
    hw( write, (UART,dr), '.' );
  }
}