串口控制FL2440（S3C2440）的LED

开发板：FL2440

芯片：S3C2440

功能：程序运行时点亮一个LED，然后利用PC机通过串口发送一个数，开发板读到这个数后点亮另外一个LED。最基本的串口控制。

代码：

Init.s

AREA |DATA|,CODE,READONLY 
ENTRY 
ldr r13, =0x1000 
IMPORT WuqiMain 
b WuqiMain 
END

include.h

#define rUTRSTAT0   (*(volatile unsigned *)0x50000010)    //UART 0 Tx/Rx status
#define rULCON0     (*(volatile unsigned *)0x50000000)    //UART 0 Line control
#define rUCON0      (*(volatile unsigned *)0x50000004)    //UART 0 Control
#define rUFCON0     (*(volatile unsigned *)0x50000008)    //UART 0 FIFO control
#define rUBRDIV0    (*(volatile unsigned *)0x50000028)    //UART 0 Baud rate divisor
#define WrUTXH0(ch) (*(volatile unsigned char *)0x50000020)=(unsigned char)(ch)
#define RdURXH0()   (*(volatile unsigned char *)0x50000027)
#define rURXH0          (*(volatile unsigned *)0X50000024)
#define rUTXH0  (*(volatile unsigned *)0X50000020)
#define rURXH0  (*(volatile unsigned *)0X50000024)

#define GPBCON (*(volatile unsigned *)0x56000010) 
#define GPBDAT (*(volatile unsigned *)0x56000014) 
#define GPBUP (*(volatile unsigned *)0x56000018)

#define uchar unsigned char
#define uint unsigned int
#define U32 unsigned int
#define U16 unsigned short
#define S32 int
#define S16 short int
#define U8  unsigned char
#define    S8  char

#define TRUE 1
#define FALSE 0

#define OK 1
#define FAIL 0

#define    ESC_KEY        0x1b

uart.h

#include "include.h"
#include <stdarg.h>



void Uart_Init(int baud)
{
    int i;
    rUFCON0 = 0x0;   //UART channel 0 FIFO control register, FIFO disable
  
 
//UART0
    rULCON0 &=0XFFFFFF00;
    rULCON0 |=0X03;           //1位起始位，8位数据位
    rUCON0  =0X0805;          //串口时钟PCLK,查询方式
    rUBRDIV0 =0X1A;
    for(i=0;i<100;i++);
}


    
//=====================================================================
void Uart_SendByte(int data)
{
   
        if(data=='\n')
        {
            while(!(rUTRSTAT0 & 0x2));
           // Delay(1);                 //because the slow response of hyper_terminal 
            WrUTXH0('\r');
        }
        while(!(rUTRSTAT0 & 0x2));   //Wait until THR is empty.
      //  Delay(1);
        WrUTXH0(data);
  
   
}               

//====================================================================
void Uart_SendString(S8 *pt)
{
    while(*pt)
        Uart_SendByte(*pt++);
}

//=====================================================================
//If you don't use vsprintf(), the code size is reduced very much.
void Uart_Printf(S8 *fmt,...)
{
    va_list ap;
    S8 str[255];

    va_start(ap,fmt);
       vsprintf(str,fmt,ap);
    Uart_SendString(str);
    va_end(ap);
}

//=====================================================================

/*
char Uart_GetKey(void)
{
    
        if(rUTRSTAT0 & 0x1)    //Receive data ready
        return rURXH0 ;
        else
            return 0;
 
}
*/

main.c

#include"include.h"
#include "uart.h"

void Delay(int count)
{
    unsigned int i;                
    while (--count != 0)        
    {
        for (i=0; i<255; i++);        // ";" 表示空语句,CPU空转。
    }                   
}

void WuqiMain(void)
{
    char buf;
    
    GPBUP = 0x00; 
    GPBCON &= ~(1<<13);
    GPBCON |= (1<<12);
    GPBCON &= ~(1<<21);    
    GPBCON |= (1<<20);
    
    while(1)
    {
        GPBDAT &= ~(1<<6);
        GPBDAT &= 0xffe;
        
        if(rUTRSTAT0 & 0X01)  //接收是否完毕 =1结束
        {
            buf=rURXH0;       //读取数据
            while(!(rUTRSTAT0 & 0X04));//是否允许发送 =1允许
            rUTXH0=buf;
        }            
        if(buf=='1')
        {
            GPBDAT &= ~(1<<10);
            
        }    

    }
}

测试一下，vc6，file——new——projects——win32consoleApplication——a simple application

#include "stdafx.h"
#include <stdio.h>
#include <string.h>


int main(int argc, char* argv[])
{
    char lpBuf[]="1";
    FILE * pFile=fopen("COM1","w");
    if(pFile==NULL)
    {
        return 1;
    }
    fwrite(lpBuf,sizeof(char),strlen(lpBuf),pFile);
    fclose(pFile);
    return 0;
}

运行后开发板两个LED亮，也可用串口调试助手发送“1”来测试。