exp_3_2.asm

单片机硬件实验代码

             ;多位二进制减法
              ORG       0000H
              LJMP      START
              ORG       0030H
      START:                
              MOV       30H,#40H       ;减数,被减数首地址和字节数
              MOV       31H,#50H
              MOV       32H,#03H
            
              MOV       R0,30H         
              MOV       R1,31H
              MOV       R7,32H
              CLR       C
       LOOP:  MOV       A,@R0
              SUBB      A,@R1              
              MOV       @R1,A
              INC       R0
              INC       R1
              DJNZ      R7,LOOP
              
              ;借位存在24H中
              CLR A
              ADDC A,#00H
              ;INC R1
              MOV       @R1,A              
              SJMP      $
              END