[MCS-51]汇编程序中函数返回跑飞问题

fly928sky · 发表于 2012-6-19 15:53:12

汇编程序中函数返回跑飞问题

代码如下：
ORG 0000H
LJMP Start

Start: ACALL Init
Main: ACALL TlTr
LJMP Main

TlTr: MOV  1001H,#03FH ;左移初始值
  MOV  1002H,#0FCH ;右移初始值
  ACALL TLeft
  ACALL TRight
  RET                              //跑飞位置1

TLeft: MOV  1000H,#006H ;循环次数
  MOV  A,1001H
  USH ACC
LLoop: SETB 1.2
  OP  ACC
  MOV  0,A
  CLR  1.2
  RR  A
  USH ACC
  ACALL Delay
  DEC  1000H
  MOV  A,1000H
  JNZ  LLoop
  RET                              //跑飞位置1

TRight: MOV  1000H,#006H ;循环次数
  MOV  A,1002H
  USH ACC
RLoop: SETB 1.2
  OP  ACC
  MOV  0,A
  CLR  P1.2
  RL  A
  PUSH ACC
  ACALL Delay
  DEC  1000H
  MOV  A,1000H
  JNZ  RLoop
  RET                              //跑飞位置1
        ;程序初始化函数
Init: SETB P1.1
  MOV  P0,#0FFH
  CLR  P1.1
  SETB P1.3
  MOV  P0,#00H
  CLR  P1.3
  RET
        ;延时函数
Delay: MOV  R5,#0EAH
  MOV  R6,#060H
DLoop: SETB C
  MOV  A,R6
  SUBB A,#00H
  MOV  A,R5
  SUBB A,#00H
  JC  DEnd
  MOV  A,R6
  DEC  R6
  JNZ  DLoop
  DEC  R5
  LJMP DLoop
DEnd: RET