S3C2440外部中断之按键中断

#include "2440addr.h"
 #define U32 unsigned int
 
static void __irq Key1_ISR(void)   //EINT3
{
 int led;
 rSRCPND = rSRCPND | (0x1<<3);//EINT1开中断请求  EINT3位置一
 rINTPND = rINTPND | (0x1<<3);//经过仲裁器选出优先级高的中断后，这个中断在INTPND寄存器中相应位置一
 led = rGPBDAT & (0x1<<6);
 if (led ==0)
  rGPBDAT = rGPBDAT | (0x1<<6);//原本是亮的，熄灭
 else
  rGPBDAT = rGPBDAT & ~(0x1<<6);//原本是灭的，点亮
}
 
static void __irq Key2_ISR(void)   //EINT4
{
 int led;
 rSRCPND = rSRCPND | (0x1<<4);
 rINTPND = rINTPND | (0x1<<4);
 if(rEINTPEND&(1<<4))
 {
  rEINTPEND = rEINTPEND | (0x1<<4);
  led = rGPBDAT & (0x1<<5);
  if (led ==0)
   rGPBDAT = rGPBDAT | (0x1<<5);
  else
   rGPBDAT = rGPBDAT & ~(0x1<<5);
 }
}
 
static void __irq Key3_ISR(void)   //EINT2
{
 int led;
 rSRCPND = rSRCPND | (0x1<<2);
 rINTPND = rINTPND | (0x1<<2);
 led = rGPBDAT & (0x1<<8);
 if (led ==0)
  rGPBDAT = rGPBDAT | (0x1<<8);
 else
  rGPBDAT = rGPBDAT & ~(0x1<<8);
}
 
void __irq Key4_ISR(void)   //EINT0
{
 int led;
 rSRCPND = rSRCPND | 0x1;
 rINTPND = rINTPND | 0x1;
 led = rGPBDAT & (0x1<<10);
 if (led ==0)
  rGPBDAT = rGPBDAT | (0x1<<10);
 else
  rGPBDAT = rGPBDAT & ~(0x1<<10);
}
 
void Main(void)
{
 int light;
 
    rGPBCON = 0x155550;//0000 0001 0101 0101 0101 0000
       rGPBUP = 0x7ff;//上拉无效
       rGPFCON = 0xaaaa;//1010 1010 1010 1010 GPF管脚均设为中断模式
   
       rSRCPND = 0x1d;//0001 1101  EINT0、2、3、4_7开
       rINTMSK = ~0x1d;//屏蔽关
       rINTPND =0x1d;
       rEINTPEND = (1<<4);
       rEINTMASK = ~(1<<4);
       rEXTINT0 = 0x22222;//0010 0010 0010 0010 0010 设计触发方式  均设为下降沿
   
       light = 0x0;
       rGPBDAT = ~light;
       
       pISR_EINT0 = (U32)Key4_ISR;
       pISR_EINT3 = (U32)Key1_ISR;
       pISR_EINT2 = (U32)Key3_ISR;
       pISR_EINT4_7 = (U32)Key2_ISR;
      
       while(1)
      ; 
}
//******************************************************************************/

SRCPND/INPND设置要保持一致，负责哪些中断的开关。INTMSK是总的中断屏蔽。EINTPEND/EINTMASK只有外部中断EINT4-EINT23需要设置，在EXTINT0寄存器中设置触发方式。

//********************************************************************************/

 pISR_EINT0-pISR_EINT4_7 定义的是中断向量入口地址，在2440addr.h文件中。如图：