GPIO输入----检测按键（EasyARM2131）

**--------------File Info----------------------------------------------------------
** File name:main.c
** Last modified Date: 2011-04-09
** Last Version:1.0
** Descriptions:The main() function example template
**
**---------------------------------------------------------------------------------
** Created by:lxliu
** Created date:2011-04-09
** Version:1.0
** Descriptions:The original version
************************************************************************************/
#include "config.h"

const uint32 BEEP = (1<<7);
const uint32 KEY1 = (1<<16);

/*************************************************************************
** 函数名称：main()
** 函数功能：GPIO输入测试
检测按键KEY1：KEY1按下，蜂鸣器蜂鸣；松开后，停止蜂鸣
** 跳线说明：需将跳线JP8和KEY1短接，JP11连接蜂鸣器
*************************************************************************/
int main (void)
{

PINSEL0 = 0x00000000; //所有引脚都设置为GPIO
PINSEL1 = 0x00000000; //
IO0DIR = BEEP; //蜂鸣器控制口输出，其余输入

while(1)
{
if((IO0PIN & KEY1) == 0) //KEY1按下，蜂鸣器蜂鸣
IO0CLR = BEEP;
else //松开后，停止蜂鸣
IO0SET = BEEP;
}
return 0;
}
/**********************************************************************************
** End Of File
***********************************************************************************/