Use PETSCII editor for building levels

.gitignore

@@ -3,3 +3,8 @@
 /itema.vs
 /bin/
 source.txt
+.source.txt
+itema.asm
+petscii/convert-screens.prg
+petscii/convert-screens.mod
+petscii/convert-screens.sym

README.md

@@ -6,3 +6,4 @@ This game requires a paddle to play. When using the VICE emulator, add the follo
 
 * [Codebase64](https://codebase64.org/doku.php?id=start)
 * [Dustlayer](https://dustlayer.com)
+* [Kick Assembler User Guide](http://www.theweb.dk/KickAssembler/webhelp/content/cpt_Introduction.html)

screens.asm → font.asm

@@ -1,4 +1,4 @@
-*=$3800
+*=$3800 "Custom character set"
 .byte	$18, $18, $18, $FF, $FF, $18, $18, $18
 .byte	$3C, $24, $24, $7E, $62, $62, $62, $62
 .byte	$7C, $44, $44, $7E, $62, $62, $62, $7E
@@ -256,59 +256,3 @@
 .byte	$00, $00, $00, $00, $00, $00, $00, $00
 .byte	$00, $00, $00, $00, $00, $00, $00, $00
 
-*=$2800
-background:
-.byte	$28, $26, $26, $26, $26, $26, $26, $26, $26, $26, $26, $26, $26, $26, $26, $26, $26, $26, $26, $26, $26, $26, $26, $26, $26, $21, $29, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20
-.byte	$24, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $25, $29, $20, $20, $20, $09, $14, $05, $0D, $01, $20, $20, $20, $20, $20
-.byte	$24, $20, $80, $81, $80, $81, $80, $81, $80, $81, $80, $81, $80, $81, $80, $81, $80, $81, $80, $81, $80, $81, $80, $81, $20, $25, $29, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20
-.byte	$24, $20, $80, $81, $80, $81, $80, $81, $80, $81, $80, $81, $80, $81, $80, $81, $80, $81, $80, $81, $80, $81, $80, $81, $20, $25, $29, $20, $08, $01, $03, $0B, $01, $14, $08, $0F, $0E, $20, $20, $20
-.byte	$24, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $25, $29, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20
-.byte	$24, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $25, $29, $20, $06, $12, $1B, $19, $01, $20, $32, $30, $32, $33, $20, $20
-.byte	$24, $20, $7F, $7F, $7F, $7F, $7F, $7F, $7F, $7F, $7F, $7F, $20, $20, $7F, $7F, $7F, $7F, $7F, $7F, $7F, $7F, $7F, $7F, $20, $25, $29, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20
-.byte	$24, $20, $80, $81, $80, $81, $80, $81, $80, $81, $80, $81, $20, $20, $80, $81, $80, $81, $80, $81, $80, $81, $80, $81, $20, $25, $29, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20
-.byte	$24, $20, $80, $81, $80, $81, $80, $81, $80, $81, $80, $81, $20, $20, $80, $81, $80, $81, $80, $81, $80, $81, $80, $81, $20, $25, $29, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20
-.byte	$24, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $25, $29, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20
-.byte	$24, $20, $20, $7F, $7F, $7F, $E0, $E0, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $E1, $E1, $20, $20, $20, $20, $20, $25, $29, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20
-.byte	$24, $20, $20, $20, $20, $7F, $7F, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $25, $29, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20
-.byte	$24, $20, $20, $20, $20, $20, $20, $7F, $7F, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $25, $29, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20
-.byte	$24, $20, $7F, $7F, $7F, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $7F, $7F, $2B, $25, $29, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20
-.byte	$24, $20, $7F, $7F, $7F, $7F, $7F, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $7F, $7F, $7F, $20, $20, $25, $29, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20
-.byte	$24, $20, $20, $7F, $80, $81, $7F, $7F, $20, $20, $20, $20, $20, $20, $20, $20, $20, $7F, $7F, $7F, $80, $81, $20, $20, $20, $25, $29, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20
-.byte	$24, $20, $80, $81, $E3, $E3, $80, $81, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $80, $81, $E3, $E3, $80, $81, $20, $25, $29, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20
-.byte	$24, $20, $20, $20, $80, $81, $7F, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $80, $81, $20, $20, $20, $25, $29, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20
-.byte	$24, $20, $20, $20, $20, $20, $7F, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $25, $29, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20
-.byte	$24, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $25, $29, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20
-.byte	$24, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $25, $29, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20
-.byte	$24, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $25, $29, $20, $20, $20, $20, $20, $40, $41, $42, $43, $44, $20, $20, $20
-.byte	$24, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $25, $29, $20, $20, $20, $20, $20, $50, $51, $52, $53, $54, $20, $20, $20
-.byte	$24, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $25, $29, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20
-.byte	$22, $27, $27, $27, $27, $27, $27, $27, $27, $27, $27, $27, $27, $27, $27, $27, $27, $27, $27, $27, $27, $27, $27, $27, $27, $23, $29, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20, $20
-.byte $ff
-
-colormap:
-.byte	$07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $00, $05, $05, $05, $05, $05, $05, $05, $05, $05, $05, $05, $05, $05
-.byte	$07, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $07, $00, $07, $05, $05, $03, $03, $03, $03, $03, $03, $03, $03, $03, $07
-.byte	$07, $0F, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $0F, $07, $00, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07
-.byte	$07, $0F, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $0F, $07, $00, $07, $03, $03, $03, $03, $03, $03, $03, $03, $03, $05, $07, $07
-.byte	$07, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $07, $00, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07
-.byte	$07, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $07, $00, $07, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $07, $07
-.byte	$07, $0F, $08, $08, $08, $08, $08, $08, $08, $08, $08, $08, $0F, $0F, $08, $08, $08, $08, $08, $08, $08, $08, $08, $08, $0F, $07, $00, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07
-.byte	$07, $0F, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $0F, $0F, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $0F, $07, $00, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07
-.byte	$07, $0F, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $0F, $0F, $03, $03, $03, $03, $03, $03, $03, $03, $03, $03, $0F, $07, $00, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07
-.byte	$07, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $07, $00, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07
-.byte	$07, $0F, $0F, $03, $03, $03, $07, $07, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $07, $07, $0F, $0F, $0F, $0F, $0F, $07, $00, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07
-.byte	$07, $0F, $0F, $0F, $0F, $03, $03, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $07, $00, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07
-.byte	$07, $0F, $0F, $0F, $0F, $0F, $0F, $03, $03, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $07, $00, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07
-.byte	$07, $0F, $03, $03, $03, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $03, $03, $08, $07, $00, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07
-.byte	$07, $0F, $08, $08, $03, $03, $03, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $03, $03, $08, $0F, $0F, $07, $00, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07
-.byte	$07, $0F, $0F, $03, $03, $03, $03, $03, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $03, $03, $03, $03, $03, $0F, $0F, $0F, $07, $00, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07
-.byte	$07, $0F, $03, $03, $07, $07, $03, $03, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $03, $03, $07, $07, $03, $03, $0F, $07, $00, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07
-.byte	$07, $0F, $0F, $0F, $03, $03, $0D, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $03, $03, $0F, $0F, $0F, $07, $00, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07
-.byte	$07, $0F, $0F, $0F, $0F, $0F, $0D, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $07, $00, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07
-.byte	$07, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $07, $00, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07
-.byte	$07, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $07, $00, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07
-.byte	$07, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $07, $00, $07, $07, $07, $07, $07, $0F, $0F, $0F, $0F, $0F, $07, $07, $07
-.byte	$07, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $07, $00, $07, $07, $07, $07, $07, $0F, $0F, $0F, $0F, $0F, $07, $07, $07
-.byte	$07, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $0F, $07, $00, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07
-.byte	$07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $00, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07, $07
-.byte $ff

itema.asm

@@ -17,10 +17,11 @@
 #import "libSprite.asm"
 #import "libInput.asm"
 #import "libScreen.asm"
-#import "screens.asm"
+#import "font.asm"
 
 BasicUpstart2(initialize)
 
+
 .var music = LoadSid("music/Nightshift.sid")      //<- Here we load the sid file
 .var demo_mode_movement_timer = $0
 
@@ -48,16 +49,17 @@ initialize:
 
     lda #$00                // Set sprite/background priority
     sta $d01b
-    
-    
+
+
+
     lda #$00                // Disable xpand-x
     sta $d01d
-    
+
     lda #$0a                // Set sprite #1 individual color
     sta $d027
     lda #$0c                // Set sprite #2 individual color
     sta $d028
-    
+
     lda #paddleSpriteData/64
     sta $07f8               // Sprite #0
     lda #ballSpriteData/64
@@ -100,7 +102,7 @@ initialize:
 
 
 /*
-    Set character set pointer to our custom set, turn off 
+    Set character set pointer to our custom set, turn off
     multicolor for characters
 */
 
@@ -113,16 +115,24 @@ and #%11101111 // by clearing bit #4 of $D016
 sta $d016
 
 /*
-    Print the first level from the second line from the top
+    Initialize IRQ
 */
-MEMCOPY(background, $0400)
-MEMCOPY(colormap, $d800)
+jsr init_irq
 
 /*
-    Initialize IRQ
+    Load the initial screen
+    $4500 - intro screen
+    $4d00 - level 1
 */
-jsr init_irq
+lda #$4d
+sta $ff
+lda #$00
+sta $fe
+jsr load_screen
 
+/*
+    Main loop
+*/
 loop:
 jmp loop
 
@@ -137,7 +147,7 @@ demo_input:
     isSmaller:
     sta temp
     lda SpriteMem+9
-    sbc #$06        // Adjust for ball radius 
+    sbc #$06        // Adjust for ball radius
     adc temp
     jsr store_xl    // Store the paddle x-position
     rts
@@ -171,27 +181,20 @@ paddle_input:
     rts
 
 init_irq:
-
-    lda #$00
-    ldx #0
-    ldy #0
-    lda #music.startSong-1
-    jsr music.init
-
     sei
     lda #<irq_1
     ldx #>irq_1
     sta $0314
-    stx $0315       // Set interrupt addr    
+    stx $0315       // Set interrupt addr
     lda #$7f
     sta $dc0d       // Timer A off on cia1/kb
     sta $dd0d       // Timer A off on cia2
-
     lda #$81
     sta $d01a       // Raster interrupts on
+    /*
     lda #$1b        // Screen ctrl: default
     sta $d011
-
+    */
     lda #$01
     sta $d012       // Interrupt at line 0
 
@@ -205,7 +208,7 @@ irq_1:
     lda #$00
     sta SpriteIndex
     jsr paddle_input
-    
+
     animation_loop:
 
         clc
@@ -223,7 +226,7 @@ irq_1:
         move_ball_normally:
             jsr move_vertically
 
-        move_paddle:    
+        move_paddle:
             jsr move_horizontally
             jsr draw_sprite
             jsr check_collision
@@ -235,12 +238,7 @@ irq_1:
         beq done
         jmp animation_loop
     done:
-        asl $d019
-// No music in the main loop
-///    inc $d020
-//    jsr music.play
-//    dec $d020
-//    dec $d020
+        asl $d019 // Clear interrupt flag
         jmp $ea81 // set flag and end
 
 /*
@@ -264,8 +262,14 @@ accelerated_movement:
         jsr store_ya
     jmp move_ball_normally
 
-*=music.location "Music"
-.fill music.size, music.getData(i)              // <- Here we put the music in memory
+// Intro screen
+.var intro_background = LoadBinary("petscii/intro.bin")
+*=$4500 "Intro"
+.fill intro_background.getSize(), intro_background.get(i)
+// Level 1
+.var lvl1_background = LoadBinary("petscii/level_1.bin")
+*=$4d00 "Level 1"
+.fill lvl1_background.getSize(), lvl1_background.get(i)
 
 // -- Sprite Data --------------------------------------------------------------
 // Created using https://www.spritemate.com

libScreen.asm

@@ -11,11 +11,12 @@ loop:
     inx
     jmp loop
 out:
-    rts:	
+    rts:
 }
 
-.const MEMCP_SRCVECT = $fb
+.const MEMCP_SRCVECT = $f9
 .const MEMCP_DSTVECT = MEMCP_SRCVECT + 2
+.const MEMCP_CNTVECT = MEMCP_DSTVECT + 2
 .macro MEMCOPY(src, dst)
 {
 // NB! The vector for index indirect addressing is little-endian
@@ -47,3 +48,80 @@ memcp_nextpage:
     jmp memcp_loop
 memcp_out:
 }
+
+/*
+    Load a screen from the address prepared in  in zeropage
+    $fe – lowest byte
+    $ff - highest byte
+ */
+load_screen:
+
+    // Start with the characters
+    lda #$00
+    sta MEMCP_DSTVECT
+    lda $fe                 // zeropage 
+    sta MEMCP_SRCVECT
+    lda #$04
+    sta MEMCP_DSTVECT+1
+    lda $ff                 // zeropage 
+    sta MEMCP_SRCVECT+1
+    lda #$00
+    sta MEMCP_CNTVECT       // Initialize low byte of counter
+    sta MEMCP_CNTVECT+1     // Initialize high byte of counter
+
+    jsr copy_loop
+
+    // Now do the colours
+    lda $fe                 // Load the low byte of the pointer
+    clc                     // Clear carry flag before addition
+    adc #$e5                // Add the LSB for modification
+    sta MEMCP_SRCVECT
+
+    lda $ff                 // Load the high byte of the pointer
+    adc #$03                // Add the MSB for modification
+    bcc noCarry             // Branch if no carry from the first addition
+    adc #$01                // Add the carry from the first addition
+    
+    noCarry:
+        sta MEMCP_SRCVECT+1
+
+    // Set the destination to colour memory at $d800
+    lda #$00
+    sta MEMCP_DSTVECT
+    lda #$d8
+    sta MEMCP_DSTVECT+1
+    lda #$00
+    sta MEMCP_CNTVECT       // Initialize low byte of counter
+    sta MEMCP_CNTVECT+1     // Initialize high byte of counter
+
+copy_loop:
+    ldy MEMCP_CNTVECT       // Load low byte of counter into Y
+
+    lda (MEMCP_SRCVECT),Y   // Load byte from source address + Y into A
+    sta (MEMCP_DSTVECT),Y   // Store byte from A at target address + Y
+
+    inc MEMCP_CNTVECT       // Increment low byte of counter
+    bne check_counter
+    inc MEMCP_CNTVECT+1     // If low byte overflowed, increment high byte
+
+check_counter:
+    lda MEMCP_CNTVECT
+    cmp #$e8                // Check if low byte of counter has reached 0xe8
+    bne continue_loop
+
+    lda MEMCP_CNTVECT+1
+    cmp #$03                // Check if high byte of counter has reached 0x03
+    bne continue_loop
+
+    jmp end_loop            // If we've copied 1000 bytes, end the loop
+
+continue_loop:
+    iny  // Increment Y
+    bne copy_loop
+    inc MEMCP_SRCVECT+1     // If Y overflowed, increment high byte of source address
+    inc MEMCP_DSTVECT+1     // If Y overflowed, increment high byte of target address
+    jmp copy_loop           // Jump back to the start of the loop
+
+end_loop:
+
+rts