main.c

来自「用c编写的s3c4510bbootloader」· C语言 代码 · 共 50 行

#include "stdio.h"
#define ARM7_ULCON0  (*(volatile unsigned *)0x03FFD000)//UART channel0 line control register
#define ARM7_UCON0  (*(volatile unsigned *)0x03FFD004)//UART channel0 control register
#define ARM7_USTAT0  (*(volatile unsigned *)0x03FFD008)//UART channel0 status register
#define ARM7_UTXBUF0  (*(volatile unsigned *)0x03FFD00c)//UART channel0 transimit holding register
#define ARM7_URXBUF0  (*(volatile unsigned *)0x03FFD010)//UART channel0 receive buffer register

#define ARM7_UBRDIV0  (*(volatile unsigned *)0x03FFD014)//Baud ratedivisor register0

#define ARM7_BRDCNT0  (*(volatile unsigned *)0x03FFD018)
#define ARM7_BRDCLK0  (*(volatile unsigned *)0x03FFD01c)


void InitUART(int Baudrate)
{
   ARM7_ULCON0=0x03;
   ARM7_UCON0=0x09;
   ARM7_UBRDIV0=Baudrate;
}

void UART0_SendByte(unsigned char data)
{
   ARM7_UTXBUF0=data;
   while(ARM7_USTAT0&0x80)
   {};
}



int main(void)
{
	unsigned char c;
	InitUART(0x500);
  while(1)
  {
  if(ARM7_USTAT0&0x20)
  {
    c=ARM7_URXBUF0;
    UART0_SendByte(c);
    
  }
  }
  return(0);
}