44B0不能响应外部中断，进不去中断服务程序

服务程序, 外部中断

#include"..\inc\44b.h"
#include"..\inc\DEF.h"
#include"..\inc\44blib.h"
void delay(int t);
void EINT4567_INIT(void);
void __irq Eint4567(void);
/************************************************************/
// eint4567 init program
/************************************************************/
void EINT4567_INIT(void)
{
rPCONG=0xffff;//使G口工作在外部中断功能
rPUPG=0x00;//使上拉电阻使能
rINTCON=0x05;
rINTMOD=0x00;
rINTMSK=~(BIT_GLOBAL|BIT_EINT4567);
}
volatile char which_int=0;
void Test_Eint()
{
Uart_Init(0,115200);
Uart_Select(0);
EINT4567_INIT();
pISR_EINT4567=(unsigned)Eint4567;
Uart_Printf(
"...this is my first test about external interrupt\n"
"****************************************************\n"
"please select the trigger style:\n"
" 1:下降沿触发方式；\n"
" 2:上升沿触发方式；\n"
" 3:双沿触发方式；\n"
" 4:低电平触发方式；\n"
" 5:高电平触发方式；\n"
"****************************************************\n"
);
switch(Uart_Getch())
{
case '1':
Uart_Printf("你选择的是下降沿触发方式\n");
rEXTINT="0x22222222";
break;
case '2':
Uart_Printf("你选择的是上升沿触发方式\n");
rEXTINT="0x44444444";
break;
case '3':
Uart_Printf("你选择的是双沿触发方式\n");
rEXTINT="0x77777777";
break;
case '4':
Uart_Printf("你选择的是低电平触发方式\n");
rEXTINT="0x00000000";
break;
case '5':
Uart_Printf("你选择的是高电平触发方式\n");
rEXTINT="0x11111111";
break;
default:
return;
}
Uart_Printf("请您按下相应键进入测试中断！\n");
while(!which_int);
switch(which_int)
{
case 1:
Uart_Printf("外部中断4中断发生\n");
break;
case 2:
Uart_Printf("外部中断5中断发生\n");
break;
case 4:
Uart_Printf("外部中断6中断发生\n");
break;
case 8:
Uart_Printf("外部中断7中断发生\n");
break;
}
rINTMSK=BIT_GLOBAL;
which_int=0;
rINTCON=0x5;
}
void __irq Eint4567(void)
{
which_int=rEXTINTPND;
rEXTINTPND="0x0f";
rI_ISPC=BIT_EINT4567;
delay(100);
}
void delay(int t)
{
int i,j;
for(i=0;i<t;i++)
for(j=0;j<1000;j++);
}
void Main(void)
{
//while(1)
// {
Test_Eint();
// }
}