text1.asm

步进电机

        ORG     0000H
START:  MOV     30H,#00H
        MOV     31H,#00H
        MOV     32H,#00H
        MOV     P2,#0FFH
        SETB    P3.0
        MOV     21H,#00H
L1:     ACALL KEY
        MOV     20H,A 
        XRL     A,#0AH
        JZ      SET0
        MOV     A,20H
        XRL     A,#0BH
        JZ      START
        MOV     A,20H
        XRL     A,#0CH
        JZ      CCW
        MOV     A,20H 
        XCH     A,30H
        XCH     A,31H
        MOV     A,31H
        SWAP    A
        ORL     A,30H
        MOV     32H,A
        MOV     P0,A
        JMP     L1 
KEY:    MOV     R3,#0F7H
        MOV     R1,#00H 
L2:     MOV     A,R3
        MOV     P1,A
        MOV     A,P1
        MOV     R4,A
        SETB    C
        MOV     R5,#04H
L3:     RLC     A
        JNC     KEYIN 
        INC     R1
        DJNZ    R5,L3 
        MOV     A,32H
        MOV     P0,A
        MOV     A,R3
        SETB    C
        RRC     A
        MOV     R3,A
        JC      L2
        JMP     KEY
KEYIN:  MOV     R7,#60H
D2:     MOV     R6,#248 
        DJNZ    R6,$
        DJNZ    R7,D2
D3:     MOV     A,P1
        XRL     A,R4
        JZ      D3
        MOV     A,R1
        MOV     DPTR,#TABLE
        MOVC    A,@A+DPTR
		RET
CCW:    CPL     P3.0
        JB      P3.0,FOR
REV:    MOV     21H,#00H
        JMP     L1
FOR:    MOV     21H,#05H
        JMP     L1
SET0:   MOV     A,32H
        CJNE    A,#00H,SETX
        JMP     L1
SETX:   MOV     R3,#20H
SET1:   MOV     R0,21H 
SET2:   MOV     A,R0
        MOV     DPTR,#TABLE1		   
        MOVC    A,@A+DPTR
        JZ      SET1
        MOV     P2,A
        LCALL    DELAY
        INC     R0
        DJNZ    R3,SET2 
        MOV     A,30H
        CJNE    A,#00H,B1
        MOV     A,31H
        CJNE    A,#00H,B2
        JMP     START
B1:     DEC     30H
        JMP     B3
B2:     MOV     30H,#09H
        DEC     31H 
        JMP     B3
B3:     MOV     A,31H
        SWAP    A
        ORL     A,30H
        MOV     32H,A
        MOV     P0,A
        JMP     SETX
DELAY: MOV     R7,#20H
D1:     MOV     R6,#248
        DJNZ    R6,$
        DJNZ    R7,D1
        RET
TABLE:  DB      01H,02H,03H,0CH
        DB      04H,05H,06H,0DH
        DB      07H,08H,09H,0EH
        DB      0AH,00H,0BH,0FH
TABLE1: DB      03H,09H,0CH,06H 
        DB      00
        DB      03H,06H,0CH,09H
        DB      00
        END