利用共阳极数码管和独立键盘连接单片的P1,P2口实现抢答器
程序如下:
#include<reg52.h>
void delay(unsigned char n)
{
unsigned int i,j;
for( i = 255; i > 0; i--)
{
for( j = n; j > 0; j--)
{
}
}
}
void main(void)
{
unsigned char i,flag;
unsigned char arr[16] = {0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8,0x80,0x90,0x88,0x83,0xC6,0xA1,0x86,0x8E};
P1 = 0xff;
P2 = 0xff;
flag = 0;