利用单片机用8255实现接口扩展

/*************** writer:shopping.w ******************/ #include <reg52.h> #include <absacc.h> #define uint unsigned int #define uchar unsigned char #define PA XBYTE[0x0000] #define PB XBYTE[0x0001] #define PC XBYTE[0x0002] #define COM XBYTE[0x0003] uchar code DSY_CODE_Queue[]= { 0xff,0xff,0xff,0xff,0xff,0xff,0xff, 0xa4,0xc0,0xc0,0x80,0xc0,0x80,0xf9,0x80, 0xff,0xff,0xff,0xff,0xff,0xff,0xff }; uchar code DSY_Index[]= { 0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80 }; void Delay(uint x) { uchar i; while(x--) { for(i=0;i<120;i++); } } void main() { uchar i,j,k; COM = 0x80; while(1) { for(j=0;j<40;j++) { for(k=0;k<8;k++) { PB = DSY_Index[k]; PA = DSY_CODE_Queue[k+i]; Delay(1); } } i = (i+1)%15; } }