Question

51单片机用汇编语言实现八个LED的全亮全灭

Answer 1

;以89c51单片机为例，假定用P1控制LED：IO_LED EQU P1;led_0 BIT P1.0;led_1 BIT P1.1;led_2 BIT P1.2;led_3 BIT P1.3;led_4 BIT P1.4;led_5 BIT P1.5;led_6 BIT P1.6;led_7 BIT P1.7; ;定义开关LED的数据，假定LED正极一端接电源，另一端通过限流电阻接I/O端口： DATA_CloseLED EQU 11111111B;DATA_OpenLED EQU 00000000B;ORG 0000HAJMP MAINORG 0030H;-----------------------;延时0.5秒程序（注：此延时函数摘自STC-ISP）DELAY500MS:;@12.000MHzPUSH 30HPUSH 31HPUSH 32HMOV 30H,#4MOV 31H,#205MOV 32H,#180NEXT:DJNZ 32H,NEXTDJNZ 31H,NEXTDJNZ 30H,NEXTPOP 32HPOP 31HPOP 30HRET;-----------------------;下面是主程序MAIN:MOV IO_LED,#DATA_CloseLED;同时关闭8个LEDLCALLDELAY500MS;延时0.5秒MOV IO_LED,#DATA_OpenLED;同时打开8个LEDLCALLDELAY500MS;延时0.5秒LJMP MAIN;循环END;上面程序演示了8个LED间隔0.5秒同时亮和灭的变化。51单片机用汇编语言实现八个LED的全亮全灭