51单片机汇编程序集(3)

                PUSH   A
                 MOV     R2,B
                 MOV     B,#10H
      NDV311   :CLR    C
                 MOV     A,R4
                RLC    A
                 MOV     R4,A
                 MOV     A,R3
                RLC    A
                 MOV     R3,A
                 MOV     A,R2
                RLC    A
                 MOV     R2,A
                 MOV     F0,C
                CLR    C
                SUBB   A,R7
                JB     F0,NDV312
                JC     NDV313
      NDV312   : MOV     R2,A
                INC    R4
      NDV313   :DJNZ   B,NDV311
                POP    A
                CLR    OV
                JZ     NDV314
                SETB   OV
      NDV314   :XCH    A,R2
                 MOV     R7,A
                RET
      ;单字节无符号除法程序 (R5R2R3R4/R7)=(R5)R2R3R4 余数R7
      ;入口    :R2,R3,R4,R7
      ;占用资源:ACC,B,F0
      ;堆栈需求:3字节
      ;出口    :(R5),R2,R3,R4,R7,OV
      NDIV41   : MOV     A,R5
                 MOV     B,R7
                DIV    AB
                PUSH   A
                 MOV     R5,B
                 MOV     B,#18H
      NDV411   :CLR    C
                 MOV     A,R4
                RLC    A
                 MOV     R4,A
                 MOV     A,R3
                RLC    A
                 MOV     R3,A
                 MOV     A,R2
                RLC    A
                 MOV     R2,A
                 MOV     A,R5
                RLC    A
                 MOV     R5,A
                 MOV     F0,C
                CLR    C
                SUBB   A,R7
                JB     F0,NDV412
                JC     NDV413
      NDV412   : MOV     R5,A
                INC    R4
      NDV413   :DJNZ   B,NDV411
                POP    A
                CLR    OV
                JZ     NDV414
                SETB   OV

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本文关键字：单片机  51单片机，单片机-工控设备 - 51单片机