count.asm

来自「基于msc单片机仿真机的仿真程序」· 汇编 代码 · 共 42 行

TEMP EQU 60H
     ORG 0000H
     AJMP MAIN
     ORG 001BH
     AJMP TIM
MAIN: 
     MOV TMOD,#01100000B;设定工作模式
     MOV TL1,#0ffh
     MOV TH1,#0ffH;设定时值
     SETB TR1      ;启动定时器
     MOV IE,#10001000B  ;开中断
     MOV TEMP,#0ffh;初始状态
     AJMP $
TIM: 
     PUSH ACC
     CLR ET1
     CLR C
     MOV A,TEMP
     RLC A
     MOV P0,A
     SETB P1.0
     ACALL DEL
     CLR P1.0
     MOV TEMP,A
     CJNE A,#00,LOOP
     MOV TEMP,#0ffh
LOOP: 
     POP ACC
     SETB ET1
     RETI
DEL:
     MOV R7,#04H
DEL1:
     MOV R6,#0
DEL2:
     MOV R5,#0
     DJNZ R5,$
     DJNZ R6,DEL2
     DJNZ R7,DEL1
     RET
     END