include<reg51.h>
unsigned char n = 0;
sbit key = P3^4;
sbit led = P1^0;
void delay()
{
unsigned int i, j;
for(i = 0; i < 100; i++) for(j = 0; j < 500; j++);
}
void readkey(void)
{
unsigned char i, j;
if(!key) {
for(i = 0; i < 10; i++)
for(j = 0; j < 120; j++); //延時消抖
if(!key) {
while(!key); //等待按鍵釋放
n++;
n %= 4; //n = 0~3
}
}
}
main()
{
while(1) {
switch(n) {
case 0: led = 1; readkey(); break; //熄滅
case 1: delay(); readkey(); //慢速閃爍
case 2: delay(); readkey(); //中速閃爍
case 3: delay(); readkey(); led = ~led; //快速閃爍
}
}
}
大致是這個意思，可以參考一下。 |
