;********************************************************
;
;               STEPPER MOTOR CONTROLLER
;			2008 1/21
;			Programed by Takashi Amoh
;
;********************************************************

        LIST            P=PIC16F84A
        INCLUDE         P16F84A.INC
        __CONFIG _HS_OSC & _WDT_OFF & _PWRTE_ON & _CP_OFF

;****************  LABEL DEFINITION  ********************
        CBLOCK  H'0C'
MODE                            ;OPERATION MODE
                                ;0=STOP 1=RIGHT 2=LEFT
COUNT1                          ;WAIT COUNTER
COUNT2                          ;WAIT COUNTER(FOR 1MSEC)
        ENDC

RB0     EQU     0               ;RB0 OF PORTB
RB1     EQU     1               ;RB1 OF PORTB
RB2     EQU     2               ;RB2 OF PORTB
RB5     EQU     5               ;RB5 OF PORTB
RB7     EQU     7               ;RB7 OF PORTB

;****************  PROGRAM START  ***********************
        ORG     0               ;RESET VECTOR
        GOTO    INIT
        ORG     4               ;INTERRUPT VECTOR
        CLRF    INTCON          ;CLEAR INTERRUPTION REG

;****************  INITIAL PROCESS  *********************
INIT
        BSF     STATUS,RP0      ;CHANGE TO BANK1
        CLRF    TRISA           ;SET PORTA ALL OUT
        MOVLW   B'00100111'     ;RB0,1,2.5=IN RB7=OUT
        MOVWF   TRISB           ;SET PORTB
        MOVLW   B'10000000'     ;RBPU=1 PULL UP NOT USE
        MOVWF   OPTION_REG      ;SET OPTION_REG
        BCF     STATUS,RP0      ;CHANGE TO BANK0
        CLRF    MODE            ;SET MODE = STOP
        CLRF    COUNT1          ;CLEAR COUNTER
        CLRF    COUNT2          ;CLEAR COUNTER
        MOVLW   B'00000101'     ;SET PORTA INITIAL VALUE
        MOVWF   PORTA           ;WRITE PORTA
        BSF     PORTB,RB7       ;SET RB7 = 1
        BTFSC   PORTB,RB5       ;RB5 = 0 ?
        GOTO    $-1             ;NO. WAIT

START
;*************  CHECK SWITCH CONDITION  *****************
        BTFSC   PORTB,RB1       ;RB1(STOP KEY) = ON ?
        GOTO    CHECK1          ;NO. NEXT
        CLRF    MODE            ;YES. SET STOP MODE
        GOTO    DRIVE           ;NO. JUMP TO MOTOR DRIVE
CHECK1
        BTFSC   PORTB,RB2       ;RB2(RIGHT KEY) = ON ?
        GOTO    CHECK2          ;NO. NEXT
        MOVLW   D'1'            ;YES. SET RIGHT MODE
        MOVWF   MODE            ;SAVE MODE
        GOTO    DRIVE           ;NO. JUMP TO MOTOR DRIVE
CHECK2
        BTFSC   PORTB,RB0       ;RB0(LEFT KEY) = ON ?
        GOTO    DRIVE           ;NO. JUMP TO MOTOR DRIVE
        MOVLW   D'2'            ;YES. SET LEFT MODE
        MOVWF   MODE            ;SAVE MODE

;********************  MOTOR DRIVE  *********************
DRIVE
        MOVF    MODE,W          ;READ MODE
        BZ      START           ;MODE = STOP
        BSF     PORTB,RB7       ;SET RB7 = 1
        BTFSC   PORTB,RB5       ;RB5 = 0 ?
        GOTO    $-1             ;NO. WAIT
        MOVLW   D'5'            ;SET LOOP COUNT(5MSEC)
        MOVWF   COUNT1          ;SAVE LOOP COUNT
LOOP    CALL    TIMER           ;WAIT 1MSEC
        DECFSZ  COUNT1,F        ;COUNT - 1 = 0 ?
        GOTO    LOOP            ;NO. CONTINUE
        BCF     PORTB,RB7       ;SET RB7 = 0
        BTFSS   PORTB,RB5       ;RB5 = 1 ?
        GOTO    $-1             ;NO. WAIT
        MOVF    PORTA,W         ;READ PORTA
        SUBLW   B'000000101'    ;CHECK MOTOR POSITION
        BNZ     DRIVE2          ;UNMATCH
        MOVF    MODE,W          ;READ MODE
        SUBLW   D'1'            ;RIGHT ?
        BZ      DRIVE1          ;YES. RIGHT
        MOVLW   B'00001001'     ;NO. SET LEFT DATA
        GOTO    DRIVE_END       ;JUMP TO PORTA WRITE
DRIVE1
        MOVLW   B'00000110'     ;SET RIGHT DATA
        GOTO    DRIVE_END       ;JUMP TO PORTA WRITE
;-------
DRIVE2
        MOVF    PORTA,W         ;READ PORTA
        SUBLW   B'000000110'    ;CHECK MOTOR POSITION
        BNZ     DRIVE4          ;UNMATCH
        MOVF    MODE,W          ;READ MODE
        SUBLW   D'1'            ;RIGHT ?
        BZ      DRIVE3          ;YES. RIGHT
        MOVLW   B'00000101'     ;NO. SET LEFT DATA
        GOTO    DRIVE_END       ;JUMP TO PORTA WRITE
DRIVE3
        MOVLW   B'00001010'     ;SET RIGHT DATA
        GOTO    DRIVE_END       ;JUMP TO PORTA WRITE
;-------
DRIVE4
        MOVF    PORTA,W         ;READ PORTA
        SUBLW   B'000001010'    ;CHECK MOTOR POSITION
        BNZ     DRIVE6          ;UNMATCH
        MOVF    MODE,W          ;READ MODE
        SUBLW   D'1'            ;RIGHT ?
        BZ      DRIVE5          ;YES. RIGHT
        MOVLW   B'00000110'     ;NO. SET LEFT DATA
        GOTO    DRIVE_END       ;JUMP TO PORTA WRITE
DRIVE5
        MOVLW   B'00001001'     ;SET RIGHT DATA
        GOTO    DRIVE_END       ;JUMP TO PORTA WRITE
;-------
DRIVE6
        MOVF    PORTA,W         ;READ PORTA
        SUBLW   B'000001001'    ;CHECK MOTOR POSITION
        BNZ     DRIVE8          ;UNMATCH
        MOVF    MODE,W          ;READ MODE
        SUBLW   D'1'            ;RIGHT ?
        BZ      DRIVE7          ;YES. RIGHT
        MOVLW   B'00001010'     ;NO. SET LEFT DATA
        GOTO    DRIVE_END       ;JUMP TO PORTA WRITE
DRIVE7
        MOVLW   B'00000101'     ;SET RIGHT DATA
        GOTO    DRIVE_END       ;JUMP TO PORTA WRITE
;-------
DRIVE8
        MOVLW   B'00000101'     ;COMPULSION SETTING

DRIVE_END
        MOVWF   PORTA           ;WRITE PORTA
        GOTO    START           ;JUMP TO START

;*************  1MSEC TIMER SUBROUTINE  *****************
TIMER
        MOVLW   D'200'          ;SET LOOP COUNT
        MOVWF   COUNT2          ;SAVE LOOP COUNT
TMLP    NOP                     ;TIME ADJUST
        NOP                     ;TIME ADJUST
        DECFSZ  COUNT2,F        ;COUNT - 1 = 0 ?
        GOTO    TMLP            ;NO. CONTINUE
        RETURN                  ;YES. COUNT END

;********************************************************
;             END OF STEPPER MOTOR CONTROLLER
;********************************************************

        END