第七章 变量进阶和点阵LED

这里我们讲一讲什么是点阵LED，所谓点的点阵LED就是我们平时在大街上看到的电子滚动屏幕，用以显示店家需要展示的消息。而深入来看，它是一个LED组成的点阵，如图所示![点阵LED原理](http://img.blog.csdn.net/20170813102704299?watermark/2/text/aHR0cDovL2Jsb2cuY3Nkbi5uZXQvaGhjaGVuY2hvbmc=/font/5a6L5L2T/fontsize/400/fill/I0JBQkFCMA==/dissolve/70/gravity/SouthEast)和我们中学学习的坐标类似，如果要想形成文字，便将点阵LED中的某些点电亮，展现各种各样的图形。我们所看见的电子屏幕的滚动，实际上是图片的动态刷新。一次只移动一个LED，形成我们所看到的滚动屏幕。下面是宋雪松老师提供的代码，详情访问www.kingst.org

#include<reg52.h>sbit ADDR0 = P1^0;sbit ADDR1 = P1^1;sbit ADDR2 = P1^2;sbit ADDR3 = P1^3;sbit ENLED = P1^4;unsigned char code image[] = {    0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x7D,0x01,0x01,0x7D,0xFF,0xFF,0xE3,0xC1,0x81,0x03,0x03,0x81,0xC1,0xE3,0xFF,0xFF,0x81,0x01,0x3F,0x3F,0x3F,0x01,0x81,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,    };  void main(){    EA = 1;    ENLED = 0;    ADDR3 = 0;    TMOD = 0x01;    TH0 = 0xFC;    TL0 = 0x67;    ET0 = 1;    TR0 = 1;    while(1);}void InterruptTimer0() interrupt 1{    static unsigned char i = 0;    static unsigned char index = 0;    static unsigned char tmr = 0;    TH0 = 0xFC;    TL0 = 0x67;    P0 = 0xFF;    switch(i)    {        case 0: ADDR2=0; ADDR1=0; ADDR0=0; i++; P0=image[index + 0];break;        case 1: ADDR2=0; ADDR1=0; ADDR0=1; i++; P0=image[index + 1];break;        case 2: ADDR2=0; ADDR1=1; ADDR0=0; i++; P0=image[index + 2];break;        case 3: ADDR2=0; ADDR1=1; ADDR0=1; i++; P0=image[index + 3];break;        case 4: ADDR2=1; ADDR1=0; ADDR0=0; i++; P0=image[index + 4];break;        case 5: ADDR2=1; ADDR1=0; ADDR0=1; i++; P0=image[index + 5];break;        case 6: ADDR2=1; ADDR1=1; ADDR0=0; i++; P0=image[index + 6];break;        case 7: ADDR2=1; ADDR1=1; ADDR0=1; i=0; P0=image[index + 7];break;        default: break;    }    tmr++;    if(tmr >= 250)    {        tmr = 0;        index++;        if(index >= 32)        {            index = 0;        }    }}

#include<reg52.h>sbit ADDR0 = P1^0;sbit ADDR1 = P1^1;sbit ADDR2 = P1^2;sbit ADDR3 = P1^3;sbit ENLED = P1^4;    unsigned char code image[30][8] = {    {0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF},  //动画帧1    {0xFF,0x7F,0xFF,0xFF,0xFF,0xFF,0xFF,0x7F},  //动画帧2    {0xFF,0x3F,0x7F,0x7F,0x7F,0x7F,0x7F,0x3F},  //动画帧3    {0xFF,0x1F,0x3F,0x3F,0x3F,0x3F,0x3F,0x1F},  //动画帧4    {0xFF,0x0F,0x9F,0x9F,0x9F,0x9F,0x9F,0x0F},  //动画帧5    {0xFF,0x87,0xCF,0xCF,0xCF,0xCF,0xCF,0x87},  //动画帧6    {0xFF,0xC3,0xE7,0xE7,0xE7,0xE7,0xE7,0xC3},  //动画帧7    {0xFF,0xE1,0x73,0x73,0x73,0xF3,0xF3,0xE1},  //动画帧8    {0xFF,0x70,0x39,0x39,0x39,0x79,0xF9,0xF0},  //动画帧9    {0xFF,0x38,0x1C,0x1C,0x1C,0x3C,0x7C,0xF8},  //动画帧10    {0xFF,0x9C,0x0E,0x0E,0x0E,0x1E,0x3E,0x7C},  //动画帧11    {0xFF,0xCE,0x07,0x07,0x07,0x0F,0x1F,0x3E},  //动画帧12    {0xFF,0x67,0x03,0x03,0x03,0x07,0x0F,0x9F},  //动画帧13    {0xFF,0x33,0x01,0x01,0x01,0x03,0x87,0xCF},  //动画帧14    {0xFF,0x99,0x00,0x00,0x00,0x81,0xC3,0xE7},  //动画帧15    {0xFF,0xCC,0x80,0x80,0x80,0xC0,0xE1,0xF3},  //动画帧16    {0xFF,0xE6,0xC0,0xC0,0xC0,0xE0,0xF0,0xF9},  //动画帧17    {0xFF,0x73,0x60,0x60,0x60,0x70,0x78,0xFC},  //动画帧18    {0xFF,0x39,0x30,0x30,0x30,0x38,0x3C,0x7E},  //动画帧19    {0xFF,0x9C,0x98,0x98,0x98,0x9C,0x1E,0x3F},  //动画帧20    {0xFF,0xCE,0xCC,0xCC,0xCC,0xCE,0x0F,0x1F},  //动画帧21    {0xFF,0x67,0x66,0x66,0x66,0x67,0x07,0x0F},  //动画帧22    {0xFF,0x33,0x33,0x33,0x33,0x33,0x03,0x87},  //动画帧23    {0xFF,0x99,0x99,0x99,0x99,0x99,0x81,0xC3},  //动画帧24    {0xFF,0xCC,0xCC,0xCC,0xCC,0xCC,0xC0,0xE1},  //动画帧25    {0xFF,0xE6,0xE6,0xE6,0xE6,0xE6,0xE0,0xF0},  //动画帧26    {0xFF,0xF3,0xF3,0xF3,0xF3,0xF3,0xF0,0xF8},  //动画帧27    {0xFF,0xF9,0xF9,0xF9,0xF9,0xF9,0xF8,0xFC},  //动画帧28    {0xFF,0xFC,0xFC,0xFC,0xFC,0xFC,0xFC,0xFE},  //动画帧29    {0xFF,0xFE,0xFE,0xFE,0xFE,0xFE,0xFE,0xFF}   //动画帧30};void main(){    EA = 1;    ENLED = 0;    ADDR3 = 0;    TMOD = 0x01;    TH0 = 0xFC;    TL0 = 0x67;    ET0 = 1;    TR0 = 1;    while(1);}void InterruptTimer0() interrupt 1{    static unsigned char i = 0;    static unsigned char tmr = 0;    static unsigned char index = 0;    TH0 = 0xFC;    TL0 = 0x67;    P0 = 0xFF;    switch(i)    {        case 0: ADDR2=0; ADDR1=0; ADDR0=0; i++; P0=image[index][0]; break;        case 1: ADDR2=0; ADDR1=0; ADDR0=1; i++; P0=image[index][1]; break;        case 2: ADDR2=0; ADDR1=1; ADDR0=0; i++; P0=image[index][2]; break;        case 3: ADDR2=0; ADDR1=1; ADDR0=1; i++; P0=image[index][3]; break;        case 4: ADDR2=1; ADDR1=0; ADDR0=0; i++; P0=image[index][4]; break;        case 5: ADDR2=1; ADDR1=0; ADDR0=1; i++; P0=image[index][5]; break;        case 6: ADDR2=1; ADDR1=1; ADDR0=0; i++; P0=image[index][6]; break;        case 7: ADDR2=1; ADDR1=1; ADDR0=1; i=0; P0=image[index][7]; break;        default: break;    }    tmr++;    if(tmr >= 250)    {           tmr = 0;        index++;        if(index >= 30)        {            index = 0;        }    }}