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<code>
; raw frame for generic 64KB cartridge images
; v 1.0 enthusi 06/2012
; this 64 KB Cartridge framework was written for http://www.rgcd.co.uk
; feel free to use/change this code and give credits :)
; you will find this document also at http://codebase64.org
; this is a VERY simple but efficient approach, you can make more 
; sophisticated usage of ROM using an own depacker routine etc....
; sources are in XA format but no special features are used
; I strongly recommend the usage of cartconv which comes with vice
;---------------------------------------------------------- 
; recent builds of VICE support the RGCD cartridge format,
; grab it at http://vice.pokefinder.org
;---------------------------------------------------------
; example usage:
; xa -M frame64kb.asm -o game_raw.bin
; cartconv -t rgcd -i game_raw.bin -o game.crt
; x64sc -cartcrt frame.crt
;----------------------------------------------------------
</code>

<code>
;no load-adress for bin-file, so no header here
*=$8000

.word launcher ;cold start
.word launcher ;warm start
.byte $c3       ;c
.byte $c2       ;b
.byte $cd       ;m
.byte $38       ;8
.byte $30       ;0

launcher
  stx $d016
  jsr $fda3     ;prepare irq
  jsr $fd50     ;init memory
  jsr $fd15     ;init i/o
  jsr $ff5b     ;init video
                ;make sure this sets up everything you need,
                ;the calls above are probably sufficient
  ldx #$fb
  txs

;clear screen and set to black
      lda #0
      ldx #250
clearloop
      sta $d800-1+250*0,x
      sta $d800-1+250*1,x
      sta $d800-1+250*2,x
      sta $d800-1+250*3,x
      dex
      bne clearloop

	sei
	lda #$00
	sta $d020
	sta $d021
        lda #$37
        sta $01
        
;----------------------------
;prepare cart-loader in stack
init_mover
        ldx #$00
loop1   lda mover,x
        sta $0100,x
        inx
        cpx #(mover_end-mover)
        bne loop1
        ;display RGCD-logo
        jsr setup_logo
        jmp $0100
;========================
mover
	lda #$00
	sta $fc
	lda #$89
	sta $fd

	lda #$01
	sta $fe
	lda #$08
	sta $ff

	ldx #$17
loop2	ldy #$00
loop3	lda ($fc),y ;8900
	sta ($fe),y ;0800
	iny
	bne loop3
        inc $fd
	inc $ff
	dex
	bne loop2

;continue on bank 1
	lda #$01 ;de00 =1
	sta $fb
;-----------------------
loop4	sta $de00

	lda #$00
	sta $fc
	lda #$80
	sta $fd

	ldx #$20
loop5	ldy #$00
loop6	lda ($fc),y ;8000 (start of bank)
	inc $01
	sta ($fe),y ;continue from 0800 on...
        dec $01
        iny
	bne loop6 ;1 page

 	inc $fd
	inc $ff
	dex
	bne loop5 ;32 pages = 8 KB

 	inc $fb ;0-7
	lda $fb
	cmp #$08
	bne loop4

        sei
        lda #$08 ;kill cart
        sta $de00
        ldx #$ff
        txs
        lda #$00
        tax
        tay
        lda $d011
        and #%11101111
        sta $d011

        ;launch main program, configure this adress here and make sure
        ;to have ZP, I/O, VIC-REGS properly set up!
        jmp $80d

mover_end

;--------------------------------
#define OFF 7
setup_logo
.(
  ldx #0
sll1
  lda text,x
  sta $f000+40*(1+OFF),x
  inx
  bne sll1

sll2
  lda text+$100,x
  sta $f000+40*(1+OFF)+$100,x
  inx
  bne sll2

;charset
csl
  lda charset+$100*0,x
  sta $f800  +$100*0,x

  lda charset+$100*1,x
  sta $f800  +$100*1,x

  lda charset+$100*2,x
  sta $f800  +$100*2,x

  lda charset+$100*3,x
  sta $f800  +$100*3,x

  lda charset+$100*4,x
  sta $f800  +$100*4,x

  lda charset+$100*5,x
  sta $f800  +$100*5,x

  lda charset+$100*6,x
  sta $f800  +$100*6,x
  dex
  bne csl

;colors
  ldx #$28
cl2
  lda #9
  sta $d800+40*(1+OFF),x
  lda #2
  sta $d800+40*(2+OFF),x
  lda #4
  sta $d800+40*(3+OFF),x
  lda #14
  sta $d800+40*(4+OFF),x
  lda #3
  sta $d800+40*(5+OFF),x
  lda #13
  sta $d800+40*(6+OFF),x
  lda #1
  sta $d800+40*(7+OFF),x
  lda #6
  sta $d800+40*(8+OFF),x
  dex
  bpl cl2

  lda #6
  sta $d800+40*(7+OFF)+18
  sta $d800+40*(7+OFF)+19
  sta $d800+40*(7+OFF)+20
  sta $d800+40*(7+OFF)+21
  sta $d800+40*(6+OFF)+19
  sta $d800+40*(6+OFF)+20

   lda #%11001110
      sta $d018    
  lda #%00010100
  sta $dd00
  rts

text
  .bin 2,0,"logo.screen"
charset
  .bin 2,0,"logo.bitmap"
after_charset
.)
;-------------------------
.dsb $8900-*,0
.bin 2,0,"heartlight.prg"
e1
.dsb $18000-*,0 ;fill up to complete 65535 Bytes
e2
</code>

You find this file and the 3 addition files
"logo.screen"
"logo.bitmap"
"heartlight.prg"
In this zip-file: {{:sourcecode:frame64kb.zip|}}