dp.asm

这是一个基于485的矩阵键盘程序源码

;显示缓冲区内的数据
DISPLAY_ALL:
        MOV    P0,#0FFH
        SETB   D_ALE
        CLR    D_ALE

        MOV    A,DIS_P
        RL     A
        MOV    DIS_P,A
        MOV    P0,A
        SETB   W_ALE
        CLR    W_ALE

        JB     ACC.6,DA0
        MOV    R0,#DIS_BUF+4
        MOV    A,@R0
        MOV    DPTR,#DIS_TAB
        MOVC   A,@A+DPTR
        SJMP   DA8

DA0:    JB     ACC.7,DA1
        MOV    R0,#DIS_BUF+7
        MOV    A,@R0
        MOV    DPTR,#DIS_TAB
        MOVC   A,@A+DPTR
        SJMP   DA8

DA1:    JB     ACC.4,DA2
        MOV    R0,#DIS_BUF+3
        MOV    A,@R0
        MOV    DPTR,#DIS_TAB
        MOVC   A,@A+DPTR
        SJMP   DA8

DA2:    JB     ACC.5,DA3
        MOV    R0,#DIS_BUF+6
        MOV    A,@R0
        MOV    DPTR,#DIS_TAB
        MOVC   A,@A+DPTR
        SJMP   DA8

DA3:    JB     ACC.3,DA4
        MOV    R0,#DIS_BUF+2
        MOV    A,@R0
        MOV    DPTR,#DIS_TAB
        MOVC   A,@A+DPTR
        SJMP   DA8

DA4:    JB     ACC.2,DA5
        MOV    R0,#DIS_BUF+5
        MOV    A,@R0
        MOV    DPTR,#DIS_TAB
        MOVC   A,@A+DPTR
        MOV    C,SYSLED
        CPL    C
        MOV    ACC.4,C
        SJMP   DA8

DA5:    JB     ACC.0,DA6
        MOV    R0,#DIS_BUF+1
        MOV    A,@R0
        MOV    DPTR,#DIS_TAB
        MOVC   A,@A+DPTR
        SJMP   DA8

DA6:    JB     ACC.1,DA7
        MOV    R0,#DIS_BUF
        MOV    A,@R0
        MOV    DPTR,#DIS_TAB
        MOVC   A,@A+DPTR
        MOV    C,WORKLED
        CPL    C
        MOV    ACC.4,C
        SJMP   DA8

DA7:    MOV    A,#0FFH
DA8:    MOV    P0,A
        SETB   D_ALE
        CLR    D_ALE
        RET

U4_MAP:
        MOV    P0,P0_MAP
        SETB   U4_ALE
        CLR    U4_ALE
        RET
;---------------------------------------
;清显示缓冲区,在等待状态显示数字0
CDISBUF:
        MOV    R7,#6
        MOV    A,#0AH
        MOV    R0,#DIS_BUF
CDISBUF_01:
        MOV    @R0,A
        INC    R0
        DJNZ   R7,CDISBUF_01
        RET
DIS_TAB:
;        0    1   2   3    4   5   6    7   8   9        S   -    E   r       _
DB      14H,0DDH,31H,91H,0D8H,92H,12H,0D5H,10H,90H,0FFH,92H,0FBH,32H,7BH,00H,0BFH