包含畫點、畫直線、畫矩形、畫圓函數等，非常實用。

#include <w78e052.h>
#include <intrins.h>
#include "ASCII.h"
#include"math.h"

#define uchar unsigned char 
#define uint unsigned int
#define NOP     _nop_()
typedef unsigned char u8;
typedef unsigned int  u16;
typedef unsigned char u32;

sbit OE     = P0^2;
sbit A1     = P0^3;
sbit B1     = P0^4;

sbit SHCP=P0^5;    //11腳SHCP    移位時鐘
sbit STCP=P0^6;    //12腳STCP    鎖存時鐘
sbit DATA=P0^7;    //數據輸入

sbit BEEP=P1^1;

unsigned char ip,tp,min,sec;
u16 time;
unsigned char PLAYBUF[64];

u8 code yi_dong[31] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,12,11,10,9,8,7,6,5,4,3,2,1,0};
u8 code tab[10] = {"0123456789"};

const uchar code table[160]=
{
0x10,0x00,0x08,0x0E,0x7F,0x70,0x22,0x40,0x14,0x40,0xFF,0x7E,0x08,0x48,0x08,0x48,
0xFF,0x48,0x08,0x48,0x2C,0x48,0x2A,0x88,0x4A,0x88,0x89,0x08,0x2A,0x08,0x10,0x08,
0x00,0x00,0x00,0x40,0x78,0x40,0x0B,0xF8,0x10,0x48,0x17,0xFE,0x20,0x48,0x7B,0xF8,
0x08,0x40,0x4B,0xFC,0x48,0x40,0x28,0x40,0x17,0xFC,0x28,0x40,0x46,0x40,0x81,0xFE,
 /*------------------------------------------------------------------------------
 ;  源文件 / 文字 : 工
 ;  寬×高（像素）: 15×
 ------------------------------------------------------------------------------*/
 0x00,0x00,0x00,0x00,0x3F,0xFC,0x01,0x00,0x01,0x00,0x01,0x00,0x01,0x00,0x01,0x00,
 0x01,0x00,0x01,0x00,0x01,0x00,0x01,0x00,0x01,0x00,0x01,0x00,0xFF,0xFE,0x00,0x00,
 /*------------------------------------------------------------------------------
 ;  源文件 / 文字 : 作
 ;  寬×高（像素）: 15×16
 ------------------------------------------------------------------------------*/
 0x08,0x80,0x0C,0x80,0x09,0x00,0x13,0xFE,0x12,0x80,0x34,0x88,0x50,0xFC,0x90,0x80,
 0x10,0x80,0x10,0x84,0x10,0xFE,0x10,0x80,0x10,0x80,0x10,0x80,0x10,0x80,0x10,0x80,
 /*------------------------------------------------------------------------------
 ;  源文件 / 文字 : 室
 ;  寬×高（像素）: 15×16
 ------------------------------------------------------------------------------*/
 0x00,0x00,0x02,0x00,0x01,0x00,0x3F,0xFE,0x20,0x04,0x40,0x08,0x3F,0xFC,0x04,0x00,
 0x08,0x20,0x1F,0xF0,0x01,0x10,0x01,0x00,0x3F,0xF8,0x01,0x00,0x01,0x00,0xFF,0xFE
};

/*******************************************************************************************/ 
      
/*******************************************************************************************/
/*******************************************************************************************/
//數據串行輸入 
void serial_input(uchar dat)    
{
 uint m;
 for(m=0;m<8;m++)
 {
  if(dat & 0x80)
   DATA=0;
  else
   DATA=1;
  SHCP=0;
  SHCP=1;
        NOP;
  NOP;
  SHCP=0;
  NOP;
  NOP;
  dat=dat<<1;
 }
}

void delay()
{
 unsigned int i = 50000;
 while(i--);
}
/*******************************************************************************************/
//并出
void serial_output()
{
 STCP=0;
 STCP=1;
}
/*******************************************************************************************/
/*******************************************************************************************/
//行顯控制
void HC138_scan(uchar temp)
{
   OE=1;
   A1=0x01 & temp;
   B1=0x01 &(temp>>1);
}
/*******************************************************************************************/
/*******************************************************************************************/
//整屏顯示
void display()
{
 uint i,j,k;
 unsigned char buf;
 serial_output();
 for(k=0;k<4;k++)              //顯示的四行
 {
 
  for(j=0;j<2;j++)         //顯示3、4列
  {
   for(i=0;i<2;i++)      // 顯示1、2列
   {
    buf = PLAYBUF[24+(k<<1)+i+(j<<5)];
    serial_input(buf);
    buf = PLAYBUF[16+(k<<1)+i+(j<<5)];
    serial_input(buf);
    buf = PLAYBUF[8+(k<<1)+i+(j<<5)];
    serial_input(buf);
    buf = PLAYBUF[(k<<1)+i+(j<<5)];
    serial_input(buf);
   }
  }
  serial_output();
  HC138_scan(k);
 }
}

void point(unsigned char x,unsigned char y,bit c)
{
 unsigned char i;

 if(x>=32) return;
 if(y>=16) return;
 i=0x80;
 i>>=x-((x>>3)<<3);

 if(c)
  PLAYBUF[(y<<1)+((x>>4)<<5)+((x>>3)&0x01)] |= i;
 else
  PLAYBUF[(y<<1)+((x>>4)<<5)+((x>>3)&0x01)] &= ~i;
}
//畫線
void line(u8  x1, u8  y1, u8  x2, u8  y2, bit color)
{
 u8  x, y, t;
 if((x1 == x2) && (y1 == y2))
  point(x1, y1, color);
 else if(fabs(y2 - y1) > fabs(x2 - x1))
 {
  if(y1 > y2)
  {
   t = y1;
   y1 = y2;
   y2 = t;
   t = x1;
   x1 = x2;
   x2 = t;
  }
  for(y = y1; y <= y2; y ++)
  {
   x = (y - y1) * (x2 - x1) / (y2 - y1) + x1;
   point(x, y, color);
  }
 }
 else
 {
  if(x1 > x2)
  {
   t = y1;
   y1 = y2;
   y2 = t;
   t = x1;
   x1 = x2;
   x2 = t;
  }
  for(x = x1; x <= x2; x ++)
  {
   y = (x - x1) * (y2 - y1) / (x2 - x1) + y1;
   point(x, y, color);
  }
 }
}

void rectangle(u8 x1,u8 y1,u8 x2,u8 y2, bit color)
{
 line(x1,y1,x2,y1, color);
 line(x1,y1,x1,y2, color);
 line(x1,y2,x2,y2, color);
 line(x2,y1,x2,y2, color);
}
void filled_rectangle(u8 x1,u8 y1,u8 x2,u8 y2, bit color)
{
 u8 i;
 for(i=y1;i<=y2;i++)
 {
  line(x1,i,x2,i, color);
 }
}
//在指定位置畫一個指定大小的圓
//(x,y):中心點
//r    :半徑
void circle(u8 x0,u8 y0,u8 r, bit color)
{
 int a,b;
 int di;
 a=0;
 b=r;
 di=3-2*r;             //判斷下個點位置的標志
 while(a<=b)
 {
  point(x0-b,y0-a, color);             //3          
  point(x0+b,y0-a, color);             //0          
  point(x0-a,y0+b, color);             //1      
  point(x0-b,y0-a, color);             //7          
  point(x0-a,y0-b, color);             //2            
  point(x0+b,y0+a, color);             //4              
  point(x0+a,y0-b, color);             //5
  point(x0+a,y0+b, color);             //6
  point(x0-b,y0+a, color);            
  a++;
  /***使用Bresenham算法畫圓**/    
  if(di<0)di +=4*a+6;  
  else
  {
   di+=10+4*(a-b);  
   b--;
  }
  point(x0+a,y0+b, color);
 }
}

void load_playbuff(unsigned char *p)
{
 unsigned char i;
 for(i=0;i<64;i++)
 {
  PLAYBUF = *p++;
 }
}