initial.asm

c51和汇编混合编程

;;Initial 8255 and lcd


           PROG SEGMENT CODE
           public Initial
           ;;STACK SEGMENT IDATA
           ;;RSEG STACK
           ;;DS 10H  ; 16 Bytes Stack
           CSEG AT 0
           USING 0 ; Register-Bank 0
;;Execution starts at address 0 on power-up.
;;SHOW_DATA(uint8 x,uint8 y)
;;R7=x, R5=y

           RSEG PROG
Initial:
       MOV     DPTR,#6FF3H   ;;INITIAL 8255
       MOV     A,#089H
       MOVX    @DPTR,A

      MOV    R0,#3EH
      CALL   OUTI
      MOV    R0,#3FH
      CALL   OUTI
      MOV    R0,#0C0H
      CALL   OUTI
      RET

    
      ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
OUTI1:
      MOV    DPTR,#6FF1H  ;;WRITE DDRAM  ADDRESS
      MOV    A,#010H      ;;E=1, RW=0, DI=0, CS2=0, CS1=0
      MOVX   @DPTR,A
      MOV    DPTR,#6FF0H
      MOV    A,R0
      MOVX   @DPTR,A
      MOV    DPTR,#6FF1H
      MOV    A,#00H
      MOVX   @DPTR,A
      MOV    DPTR,#6FF1H
      MOV    A,#03H
      MOVX   @DPTR,A
      RET
      
OUTD1:
      MOV    DPTR,#6FF1H   ;;WRITE DISPLAY DATA
      MOV    A,#014H       ;;E=1, RW=0, DI=1, CS2=0, CS1=0
      MOVX    @DPTR,A
      MOV    DPTR,#6FF0H
      MOV    A,R0
      MOVX   @DPTR,A
      MOV    DPTR,#6FF1H
      MOV    A,#04H
      MOVX   @DPTR,A
      MOV    DPTR,#6FF1H
      MOV    A,#07H
      MOVX   @DPTR,A
      RET
      
OUTI2:
      MOV    DPTR,#6FF1H    ;;WRITE DDRAM  ADDRESS
      MOV    A,#012H        ;;E=1, RW=0, DI=0, CS2=1, CS1=0
      MOVX   @DPTR,A
      MOV    DPTR,#6FF0H
      MOV    A,R0
      MOVX   @DPTR,A
      MOV    DPTR,#6FF1H
      MOV    A,#00H
      MOVX   @DPTR,A
      MOV    DPTR,#6FF1H
      MOV    A,#03H
      MOVX   @DPTR,A
      RET
OUTD2:
      MOV    DPTR,#6FF1H   ;;WRITE DISPLAY DATA
      MOV    A,#016H       ;;E=1, RW=0, DI=1, CS2=1, CS1=0
      MOVX    @DPTR,A
      MOV    DPTR,#6FF0H
      MOV    A,R0
      MOVX   @DPTR,A
      MOV    DPTR,#6FF1H
      MOV    A,#04H
      MOVX   @DPTR,A
      MOV    DPTR,#6FF1H
      MOV    A,#07H
      MOVX   @DPTR,A
      RET
      
OUTI3:
      MOV    DPTR,#6FF1H    ;;WRITE DDRAM  ADDRESS
      MOV    A,#011H        ;;E=1, RW=0, DI=0, CS2=0, CS1=1
      MOVX   @DPTR,A
      MOV    DPTR,#6FF0H
      MOV    A,R0
      MOVX   @DPTR,A
      MOV    DPTR,#6FF1H
      MOV    A,#00H
      MOVX   @DPTR,A
      MOV    DPTR,#6FF1H
      MOV    A,#03H
      MOVX   @DPTR,A
      RET
      
OUTD3:
      MOV    DPTR,#6FF1H   ;;WRITE DISPLAY DATA
      MOV    A,#015H       ;;E=1, RW=0, DI=1, CS2=0, CS1=1
      MOVX    @DPTR,A
      MOV    DPTR,#6FF0H
      MOV    A,R0
      MOVX   @DPTR,A
      MOV    DPTR,#6FF1H
      MOV    A,#04H
      MOVX   @DPTR,A
      MOV    DPTR,#6FF1H
      MOV    A,#07H
      MOVX   @DPTR,A
      RET

OUTI:
      CALL   OUTI1
      CALL   OUTI2
      CALL   OUTI3
      RET


      end