; ### Public Domain for all Vecfreaks
; ### Joystick movement test
; ### Code & comments by man@sci.fi
; ### Debugging by marq@iki.fi


; ### Needed BIOS routines


WAITRECAL       equ     $f192
INTENSITY       equ     $f2ab
PRINTSTR        equ     $f37a


JOYDIGITAL      equ     $f1f8   ; Reads joystick positions
JOY1XENABLE     equ     $c81f   ; Enables joystick 1 X
JOY1YENABLE     equ     $c820   ; Enables joystick 1 Y
JOY2XENABLE     equ     $c821   ; Enables joystick 2 X
JOY2YENABLE     equ     $c822   ; Enables joystick 2 Y
JOY1X           equ     $c81b   ; Joystick 1 left/right
JOY1Y           equ     $c81c   ; Joystick 1 up/down


; ### Here we go.


        org     0


; ### The required init block.


        fcb     $67,$20          
        fcc     "GCE MANU"
        fcb     $80             ; All text ends with $80
        fdb     $fe38           ; Play song "$fe38" from ROM
        fdb     $f850           ; Width, height
        fdb     $30b8           ; y-position, x-position
        fcc     "JOYSTICK TEST"
        fcb     $80,$0          ; Init block ends with $0


; ### Okay, this sets up the joystick checks, and only
; ### allows them for joystick 1, thus saving us a few
; ### hundred cycles. Don't forget to set joystick 2
; ### to 0, if you don't need it.


        lda     #1              ; 1 is the flag to enable
        sta     JOY1XENABLE     ; joystick 1 X
        lda     #3              ; 3 is the flag to enable
        sta     JOY1YENABLE     ; joystick 1 Y
        lda     #0
        sta     JOY2XENABLE     ; 5 would enable this
        sta     JOY2YENABLE     ; 7 would enable this


; ### Here begins the actual joystick reading.


tikku   jsr     WAITRECAL       ; BIOS recalibration


        lda     #95             
        jsr     INTENSITY       ; Sets intensity to 95  


        jsr     JOYDIGITAL      ; Reads joystick
        lda     JOY1X           ; Joy 1 X position to A
        lbeq    noxmove         ; If 0 -> jump to noxmove
        lbmi    lmove           ; If negative -> lmove


; ### If something else (positive)
; ### the joystick has been moved right. Right.


rmove   lda     #40             ; Y-coordinate
        ldb     #-50            ; X-coordinate
        ldu     #rtext          ; Get the text
        jsr     PRINTSTR
        bra     xready          ; Jump to xready


; ### Joystick has been moved left.


lmove   lda     #40             ; Y-coordinate
        ldb     #-50            ; X-coordinate
        ldu     #ltext          ; Get the text
        jsr     PRINTSTR
        bra     xready          ; Jump to xready


; ### Joystick hasn't been moved left or right.


noxmove lda     #40             ; Y-coordinate
        ldb     #-50            ; X-coordinate
        ldu     #noxtext        ; Get the text
        jsr     PRINTSTR


; ### Done with checking if the joystick
; ### was moved left or right, now checking
; ### if it was moved up or down.


xready  lda     JOY1Y           ; Joy 1 Y position to A
        beq     noymove         ; If 0 -> jump to noymove
        bmi     dmove           ; If negative -> dmove


; ### If something else (positive)
; ### the joystick has been moved up.


umove   lda     #20             ; Y-coordinate
        ldb     #-50            ; X-coordinate
        ldu     #utext          ; Get the text
        jsr     PRINTSTR
        bra     yready          ; Jump to yready


; ### Joystick has been moved down.


dmove   lda     #20             ; Y-coordinate
        ldb     #-50            ; X-coordinate
        ldu     #dtext          ; Get the text
        jsr     PRINTSTR
        bra     yready          ; Jump to yready


; ### Joystick hasn't been moved up or down.
        
noymove lda     #20             ; Y-coordinate
        ldb     #-50            ; X-coordinate
        ldu     #noytext        ; Get the text
        jsr     PRINTSTR


; ### Done with checking if the joystick has
; ### been moved up or down - so let's go
; ### back to the beginning and check all again.


yready  lbra    tikku           ; Repeat        


; ### You need LBRA, because BRA is too short a jump
; ### to jump to the beginning all the way from here


; ### Then all the texts that are needed
; ### to be displayed.


noxtext fcc     "NO LEFT OR RIGHT"
        fcb     $80


ltext   fcc     "LEFT !!!"
        fcb     $80


rtext   fcc     "RIGHT !!!"
        fcb     $80


noytext fcc     "NO UP OR DOWN"
        fcb     $80


utext   fcc     "UP !!!"
        fcb     $80


dtext   fcc     "DOWN !!!"
        fcb     $80