效果展示：
本程序代码为《手把手教你学51单片机》7.6的课后练习题6，并且已经在KST-51 v1.3.2开发板验证通过。
#include <reg52.h>
sbit ADDR0 = P1^0;
sbit ADDR1 = P1^1;
sbit ADDR2 = P1^2;
sbit ADDR3 = P1^3;
sbit ENLED = P1^4;
//点阵数码管图片帧
unsigned char code images[6][8] = {
{0x00,0x7E,0x7E,0x7E,0x7E,0x7E,0x7E,0x00}, //8x8点阵从外圈数第1圈显示的图片帧
{0xFF,0x81,0xBD,0xBD,0xBD,0xBD,0x81,0xFF}, //8x8点阵从外圈数第2圈显示的图片帧
{0xFF,0xFF,0xC3,0xDB,0xDB,0xC3,0xFF,0xFF}, //8x8点阵从外圈数第3圈显示的图片帧
{0xFF,0xFF,0xFF,0xE7,0xE7,0xFF,0xFF,0xFF}, //8x8点阵从外圈数第4圈显示的图片帧
{0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF}, //8x8点阵全部不显示的图片帧
{0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00} //8x8点阵全部显示的图片帧
};
//数码管数值真值表
unsigned char code LedChar[16] = {
0xC0, 0xF9, 0xA4, 0xB0, 0x99, 0x92, 0x82, 0xF8,
0x80, 0x90, 0x88, 0x83, 0xC6, 0xA1, 0x86, 0x8E
};
//数码管顺时针旋转真值表
unsigned char code LedCW[6] = {
0xF7, 0xEF, 0xDF, 0xFE, 0xFD, 0xFB
};
//数码管显示缓冲区
unsigned char LedBuff[7] = {
0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF
};
bit flag1s = 0; //1s标志位
bit flag50ms = 0; //50s标志位
bit flag100ms = 0; //100ms标志位
bit flag3s = 0; //3s标志位
unsigned char index = 0; //图片帧索引变量
bit flagcyclecnt = 0; //图片循环次数标志位
void main(){
unsigned char sec = 0; //计秒初始值
unsigned char tempLedBuff = 0; //8个LED小灯转换变量
unsigned char buff[3]; //中间转换缓冲区
signed char i = 0;
unsigned char j = 0;
bit flagLedDP = 0; //数码管小点标志位
bit dir = 1; //图片帧播放方向变量
unsigned char cyclecnt = 0; //图片帧播放次数变量
EA = 1; //使能总中断
ENLED = 0; //使能LED
TMOD &= 0xF0; //设置Timer0工作模式1
TMOD |= 0x01;
TH0 = 0xFC; //为Timer0赋初值0xFC67，定时1ms
TL0 = 0x67;
ET0 = 1; //使能Timer0中断
TR0 = 1; //启动Timer0
while(1){
if(flag1s){ //1s标志位
flag1s = 0; //1s标志位清零
flagLedDP = ~flagLedDP; //1秒数码管小点标志位取反
if(sec < 255){ //如果秒数小于255
sec++; //秒计数自加1
tempLedBuff++; //LED小灯当前值自加1
}
else{
sec = 0; //秒数清零
tempLedBuff = 0; //LED小灯值清零
}
}
if(flag100ms){ //100ms定时位
flag100ms = 0; //100ms定时位清零
if(j >= 5){ //循环数码管旋转真值表的数组下标
j = 0;
}
else{
j++;
}
}
if(flag50ms){ //50ms定时位
flag50ms = 0; //50ms定时位清零
if(dir){ //如果dir = 1
index++; //图片帧播放索引每次加1，图片帧正向播放
if(index >= 4){ //图片帧播放到第4帧
dir = 0; //dir置0
}
}
else{ //如果dir = 0，图片帧索引每次减1，图片反向播放
index--;
if(index <= 0){ //图片索引播放到第0帧
dir = 1; //dir置1
cyclecnt++; //循环播放变量加1，也就是说正向播放后又反向播放了1次后加1。
}
}
if(cyclecnt >= 5){ //如果图片帧循环播放了5次
index = 5; //图片播放第5帧，即LED点阵全部点亮
flagcyclecnt = 1; //图片循环次数标志位置1
if(flag3s){ //3s定时位
flag3s = 0; //3s定时位清零
index = 0; //图片帧索引清零
cyclecnt = 0; //图片帧播放次数清零
flagcyclecnt = 0; //图片循环次数标志位置清零
dir = 1; //dir置1
}
}
}
//将sec按十进制位从低到高依次提取到buff数组中，由于sec最大只有255，所以只计算三位
buff[0] = sec % 10;
buff[1] = sec / 10 % 10;
buff[2] = sec / 100 % 10;
//从最高为开始，遇到0不显示(赋值0xFF)，遇到非0退出for循环
for(i = 2; i >= 1; i--){
if(buff[i] == 0){
LedBuff[i] = 0xFF;
}
else{
break;
}
}
//将剩余的有效数字位如实转换，for()起始未对j操作，j即保持上个循环结束时的值
for( ; i >= 0; i--){
LedBuff[i] = LedChar[buff[i]];
}
//如果flagLedDP置1了，说明1秒的时间到，在当前LedCW的元素上面与运算0x7F，点亮数码管小点
//下一秒flagLedDP标志位置0，则直接显示当前旋转数码管的段位
if(flagLedDP){
LedBuff[3] = LedCW[j] & 0x7F;
LedBuff[4] = LedCW[j] & 0x7F;
LedBuff[5] = LedCW[j] & 0x7F;
}
else{
LedBuff[3] = LedCW[j];
LedBuff[4] = LedCW[j];
LedBuff[5] = LedCW[j];
}
//LED小灯当前值取反，赋给LedBuff[6]，待每1ms进定时器中断刷新显示出来。取反的原因在于每个LED小灯低电平点亮。
LedBuff[6] = ~tempLedBuff;
}
}
/* 定时器1中断服务函数 */
void interruptTimer0() interrupt 1{
static unsigned int cnt_1 = 0;
static unsigned int cnt_2 = 0;
static unsigned int cnt_3 = 0;
static unsigned int cnt_4 = 0;
static unsigned char i = 0;
TH0 = 0xFC; //重新加载初值
TL0 = 0x67;
cnt_1++;
if(cnt_1 >= 1000){
cnt_1 = 0;
flag1s = 1;
}
cnt_2++;
if(cnt_2 >= 100){
cnt_2 = 0;
flag100ms = 1;
}
cnt_3++;
if(cnt_3 >= 50){
cnt_3 = 0;
flag50ms = 1;
}
if(flagcyclecnt){ //图片循环次数标志位置1
cnt_4++; //进入中断次数cnt_4开始自加1
if(cnt_4 >= 3000){ //进入中断3000次，即3s
cnt_4 = 0; //进去中断次数cnt_4清零
flag3s = 1; //3s标志位置1
}
}
//以下代码完成8x8点阵，数码管和LED小灯的动态扫描刷新
P0 = 0xFF; //显示消隐
switch(i){
case 0: ADDR3 = 1; ADDR2 = 0; ADDR1 = 0; ADDR0 = 0; i++; P0 = LedBuff[0]; break;
case 1: ADDR3 = 1; ADDR2 = 0; ADDR1 = 0; ADDR0 = 1; i++; P0 = LedBuff[1]; break;
case 2: ADDR3 = 1; ADDR2 = 0; ADDR1 = 1; ADDR0 = 0; i++; P0 = LedBuff[2]; break;
case 3: ADDR3 = 1; ADDR2 = 0; ADDR1 = 1; ADDR0 = 1; i++; P0 = LedBuff[3]; break;
case 4: ADDR3 = 1; ADDR2 = 1; ADDR1 = 0; ADDR0 = 0; i++; P0 = LedBuff[4]; break;
case 5: ADDR3 = 1; ADDR2 = 1; ADDR1 = 0; ADDR0 = 1; i++; P0 = LedBuff[5]; break;
case 6: ADDR3 = 1; ADDR2 = 1; ADDR1 = 1; ADDR0 = 0; i++; P0 = LedBuff[6]; break;
case 7: ADDR3 = 0; ADDR2 = 0; ADDR1 = 0; ADDR0 = 0; i++; P0 = images[index][0]; break;
case 8: ADDR3 = 0; ADDR2 = 0; ADDR1 = 0; ADDR0 = 1; i++; P0 = images[index][1]; break;
case 9: ADDR3 = 0; ADDR2 = 0; ADDR1 = 1; ADDR0 = 0; i++; P0 = images[index][2]; break;
case 10: ADDR3 = 0; ADDR2 = 0; ADDR1 = 1; ADDR0 = 1; i++; P0 = images[index][3]; break;
case 11: ADDR3 = 0; ADDR2 = 1; ADDR1 = 0; ADDR0 = 0; i++; P0 = images[index][4]; break;
case 12: ADDR3 = 0; ADDR2 = 1; ADDR1 = 0; ADDR0 = 1; i++; P0 = images[index][5]; break;
case 13: ADDR3 = 0; ADDR2 = 1; ADDR1 = 1; ADDR0 = 0; i++; P0 = images[index][6]; break;
case 14: ADDR3 = 0; ADDR2 = 1; ADDR1 = 1; ADDR0 = 1; i = 0; P0 = images[index][7]; break;
default: break;
}
}