基于单片机的点阵式LED滚动汉字显示屏仿真设计

　　利用单片机C语言实现“2008北京欢迎您!”10个字的滚动显示，阿拉伯数字和标点符号按16×8点阵编码，汉字按16×16点阵编码， “2008北京欢迎您!”字型码表如下：

　　{0x00,0x00,0x0C,0x1C,0x10,0x24,0x10,0x24,0x10,0x44,0x10,0x84,0x0F,0x0E,0x00,0x00},

　　{0x00,0x00,0x07,0xF0,0x08,0x08,0x10,0x04,0x10,0x04,0x08,0x08,0x07,0xF0,0x00,0x00},

　　{0x00,0x00,0x07,0xF0,0x08,0x08,0x10,0x04,0x10,0x04,0x08,0x08,0x07,0xF0,0x00,0x00},

　　{0x00,0x00,0x0E,0x38,0x11,0x44,0x10,0x84,0x10,0x84,0x11,0x44,0x0E,0x38,0x00,0x00},

　　{0x00,0x00,0x0E,0x04,0x08,0x0C,0x08,0x0C,0x08,0x08,0x08,0x10,0xFF,0xFE,0x00,0x00},

　　{0x00,0x00,0x3F,0xFC,0x41,0x02,0x42,0x02,0x06,0x02,0x0E,0x06,0x0C,0x0C,0x00,0x00},

　　{0x00,0x00,0x20,0x04,0x20,0x08,0x27,0x98,0x24,0xB0,0x24,0x82,0xA4,0x81,0x64,0xFE},

　　{0x24,0x80,0x24,0x80,0x24,0xA0,0x27,0xB0,0x60,0x1C,0x20,0x08,0x00,0x00,0x00,0x00},

　　{0x28,0x04,0x24,0x08,0x22,0x32,0x21,0xC2,0x26,0xC2,0x38,0x34,0x04,0x04,0x18,0x08},

　　{0xF0,0x30,0x17,0xC0,0x10,0x60,0x10,0x18,0x14,0x0C,0x18,0x06,0x10,0x04,0x00,0x00},

　　{0x02,0x02,0x82,0x04,0x73,0xF8,0x20,0x04,0x00,0x02,0x3F,0xE2,0x20,0x42,0x40,0x82},

　　{0x40,0x02,0x3F,0xFA,0x20,0x02,0x20,0x42,0x20,0x22,0x3F,0xC2,0x00,0x02,0x00,0x00},

　　{0x01,0x00,0x02,0x04,0x0C,0x1C,0x3F,0xC0,0xC0,0x1C,0x09,0x02,0x16,0x02,0x60,0x92},

　　{0x20,0x4A,0x2F,0x82,0x20,0x02,0x24,0x0E,0x22,0x00,0x31,0x90,0x20,0x0C,0x00,0x00},

　　{0x00,0x00,0x00,0x08,0x1F,0xDC,0x3F,0x08,0x3C,0x00,0x30,0x00,0x00,0x00,0x00,0x00},

　　{0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00}。

(a)主程序流程图 (b)中断服务程序流程图

图3. 程序流程图

　　动态扫描显示程序代码如下：

　　while (1)

　　{for (i=0;i8;i++) //显示左半边屏幕

　　{ P0=*(p+offset+2*i);

　　P2=i|0x90; //P2.4=1,P2.3=0 选中U3, 输出扫描码给U7

　　delay();

　　P0=*(p+offset+2*i+1);

　　P2=i|0x08; //P2.4=0,P2.3=1 选中U2, 输出扫描码给U6

　　delay(); }

　　for (i=8;i16;i++) //显示右半边屏幕

　　{ P0=*(p+offset+2*i);

　　P2=(i-8)|0xC0; //P2.6=1 P2.5=0, P2.4=0 选中U5,输出扫描码U9

　　delay();

　　P0=*(p+offset+2*i+1);

　　P2=(i-8)|0x20; //P2.5=1 P2.4=0, P2.3=0 选中U4,输出扫描码U8

　　delay();

　　} }