;********************************************************************
 ; Filename: LAB6.ASM                                               *
 ; Delays and Sequences with Interupts.                              *
 ; RA 2-4 = LED Outputs
 ; RB 1-5 = LED Outputs
 ;  RB0  = Interrupt SW
 ; RB5,6  = Change Timer
 ;
 ;                                                                  *
 ;********************************************************************

        #include    <GENERAL.H>     ;This is the header file you created for this lab#1

 KEY        EQU     0X0C        ;This is the user defined DRAM area that
COUNT   EQU     0X0D        ; uses the 68 bytes GPR: range from 0X0C-0X4F
TEMP_W  EQU     0X13        ; Define Temp register for W
TEMP_S  EQU     0X14        ; Define temp register for Status
LCOUNT  EQU     0x15        ; Define "Lightcount" register for ISR
COUNT1  EQU     0X20        ; Inner loop Counter - defined by RB6
COUNT2  EQU     0X21        ; middle loop Counter- defined by RB7
COUNT3  EQU     0X22        ; outer loop Counter



        __CONFIG    0X3FF6  ;This is the control bits for CONFIG register, WDT disabled (0x3FF6 to enable)

        GOTO    START

        ORG     0X0004      ;Regular INT vector


;This is the area where your interrupt service routine goes

PUSH
;This stores the current W and STATUS registers in temporary locations during ISRS
    MOVWF TEMP_W
    SWAPF STATUS,W
    MOVWF TEMP_S
    BTFSC INTCON,INTF   ;check if RB0 Interrupt has occured
    GOTO  ISR       ; Goes to ISR for B0

ISR
;ISR for RB0 interrupt
    INCF    LCOUNT,F
    BCF     INTCON,INTF
    GOTO    POP

POP
;This restores the original W & STATUS registers before returning to the main program
    SWAPF TEMP_S,W
    MOVWF STATUS
    SWAPF TEMP_W,F
    SWAPF TEMP_W,W
    RETFIE

; Main Program

START

        ; ************ Start Initial Values Set *****************************
;setup Option_Reg
    MOVLW   0XFF
    MOVWF   OPTION_REG  ;turn on WDT, set prescaler to 128, define RB0 to rising edge
    CLRW

;Setup TRISA/B
    CLRF    PORTA ; Clears ports a and b
    CLRF    PORTB
    BSF     STATUS,RP0  ;set bank1 TRIS REGs
    MOVLW   0XF0
    MOVWF   TRISA       ;set RA0-RA4 as outputs, RA5-7 as Inputs
    MOVLW   b'11000001' ;
    MOVWF   TRISB       ;set RB0 Input, RB1-RB3 as outputs; RB4-7 as Inputs
    BCF     STATUS,RP0  ;switch to bank 0, normal ops
    CALL    POST_LEDS


MAIN
;Main Loop for checking switch status
CLRWDT
BTFSS   PORTB,6
MOVLW   0XFF
MOVLW   0X00
MOVWF   COUNT1
BTFSS   PORTB,7
MOVLW   0XAA
MOVLW   0X00
MOVWF   COUNT2
BTFSS   PORTB,0
;CALL   AllLights
;CALL   YLWLED

GOTO    MAIN
;
;
POST_LEDS

;POST LED - power on with .48sec delay for ops check
    MOVLW   0x2E    ;set initial delay for POST check
    MOVWF   COUNT1
    MOVLW   0X58
    MOVWF   COUNT2
    MOVLW   0XFF    ; turn on LED's
    MOVWF   PORTA       ; at porta
    MOVWF   PORTB       ; and port b
    CALL    DELAY       ;call the 0.48second delay
    CALL    DELAY       ;DO IT AGAIN
    CLRF    PORTA       ;turn off port A
    CLRF    PORTB       ;turn off port B
    CALL    DELAY       ;call .48s delay
    MOVLW   0x00
    MOVWF   COUNT1
    MOVWF   COUNT2
    MOVWF   LCOUNT;
RETURN

    AllLights
                        ;clear wdt
    MOVLW   0XFF        ;set all bits high
    MOVWF   PORTA       ;Set porta high
    MOVWF   PORTB       ;Set PortB high
    CALL    DELAY   ;delay for .48 sec
                        ;clear wdt
    MOVLW   0x00        ;set all off
    MOVWF   PORTA       ;TURN OFF
    MOVWF   PORTB       ;TURN OFF
    CALL    DELAY   ;delay for .48 sec
                        ;clear wdt

GOTO MAIN

GRNRED
                    ;Clear WDT
    MOVLW   b'00001011' ;values for red and green PortA
    MOVWF   PORTA       ;
    MOVLW   b'00000100' ;values for B
    MOVWF   PORTB

GOTO MAIN

YLWLED
    CLRWDT              ;Clear WDT
    MOVLW   b'00000100' ;values for ylw leds
    MOVWF   PORTA
    MOVLW   b'00001011' ;values for ylw leds
    MOVWF   PORTB
    CALL    DELAY   ;33msec flash
    MOVLW   b'00000000' ;turn off LEDs
    MOVWF   PORTA       ; for 33msec
    MOVWF   PORTB       ;makes'em flash fast
    CALL    DELAY

GOTO MAIN


DELAY

        ;2449991 cycles uses C1=2E, C2=58, C3=06
;Variable Delay, set from PortB6:7

;   movlw   0x2E    ;  d46
;   movwf   COUNT1  ; moved to count 1
;   movlw   0x58    ; d88
;   movwf   COUNT2  ; moved to count 2
    movlw   0x06    ; d06
    movwf   COUNT3  ; in count 3
Delay_0
    decfsz  COUNT1, f   ; Count down, d46 to 0
    goto    $+2         ; skip to next goto
    decfsz  COUNT2, f   ; decrements d88 to 0
    goto    $+2         ; skip two lines
    decfsz  COUNT3, f   ; decrement from d06 to 0
    goto    Delay_0     ; return to Delay_0

    nop     ;5 cycles
    nop     ; of
    nop     ; doing
    nop     ; nothing
    nop     ;

            ;6 cycles (including call)
    return

END