fs.asm

来自「51系列单片机的汇编程序包」· 汇编 代码 · 共 55 行

    ORG 0000H
    AJMP START


START:MOV TOMD,#20H
      MOV TH1,#F3H
      MOV TL1,#F3H
      SETB TR1
      MOV SCON,#50H
      MOV PCON,#80H
BEGIN:MOV R0, #30H
      MOV R3,#05H
      MOV R5,#00H;累加寄存器
      MOV SBUF,R3
      MOV A,R0
      ADD A,R3
      MOV R5,A
  TR0:JBC TI,TR1
      AJMP TR0
  TR1:MOV SBUF,R5;发送校验码
      MOV R5,#00H
  TR2:JBC TI,TR3
      AJMP TR2
  TR3:JBC RI,TR4
      AJMP TR3
  TR4:MOV A,SBUF
      JZ TR5
      AJMP START
  TR5:MOV A,@R0
      MOV SBUF,A
      ADD A,R5
      MOV R5,A
      INC R0
  TR6:JBC TI,TR7
      AJMP TR6
  TR7: DJNZ R3,TR5
      MOV SBUF,R5 ;
      MOV R5,#00H
  TR8:JBC TI,TR9
      AJMP TR8
  TR9:JBC RI,TR10
      AJMP TR9
  TR10:MOV A,SBUF
      JZ TR11
      AJMP BEGIN
  TR11:RET

   END