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--- base:code_frame_for_64_kb_crt-images_i.e._for_rgcd [2015-04-17 04:30] – external edit 127.0.0.1
+++ base:code_frame_for_64_kb_crt-images_i.e._for_rgcd [2015-04-22 19:55] (current) – groepaz
@@ Line 1: / Line 1: @@
+<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|}}