Feature/text scroller

itema.asm

@@ -7,13 +7,24 @@
 
 // import our sprite library
 #import "spritelib.asm"
+#import "textscroller.asm"
 #import "music/music.asm"
 
 BasicUpstart2(initialize)
 
 // Initialize
 initialize:
 	jsr $e544			// clear screen
+
+	lda #00 			// black sceen & background
+	sta $d020
+	sta $d021
+
+	lda #$ff
+	sta $d000			// set x position of sprite
+
+	lda #$ff
+	sta $d001			// set y position of sprite
 
 	lda #%00000011		// enable sprites
 	sta $d015
@@ -42,8 +53,11 @@ initialize:
 	sta $07f9			// sprite #2
 
 	jsr init_spritelib
+	jsr initScroller		// setup text scroller
+	jsr initMusic		// setup music
+
+	jsr interrupts		// setup interrupts
 
-jsr startMusic
 loop:
 	lda #00					// wait until the screen refreshes
 !:	cmp $d012	
@@ -57,6 +71,29 @@ loop:
 
 jmp loop
 
+interrupts: sei					// set up interrupt
+			lda #$7f
+			sta $dc0d			// turn off the CIA interrupts
+			sta $dd0d
+			and $d011			// clear high bit of raster line
+			sta $d011		
+
+			ldy #00				// trigger on first scan line
+			sty $d012
+
+			lda #<handler		// load interrupt address
+			ldx #>handler
+			sta $0314
+			stx $0315
+
+			lda #$01 			// enable raster interrupts
+			sta $d01a
+			cli
+			rts
+
+handler:	jsr music.play
+			jsr noscroll
+			jmp $EA81
 
 // -- Sprite Data --------------------------------------------------------------
 // Created using https://www.spritemate.com
@@ -82,4 +119,4 @@ spriteData:
 .byte %00110111,%00000000,%00000000
 .byte %00000101,%01111101,%00000000
 .byte %00001101,%01010101,%00000000
-.byte %00000011,%11011100,%00000000
+.byte %00000011,%11011100,%00000000

music/music.asm

@@ -5,39 +5,39 @@
 //---------------------------------------------------------
 			.var music = LoadSid("Nightshift.sid")		//<- Here we load the sid file
 
-startMusic:	lda #$00
+initMusic:	lda #$00
 			// sta $d020
 			// sta $d021
 			ldx #0
 			ldy #0
 			lda #music.startSong-1						//<- Here we get the startsong and init address from the sid file
 			jsr music.init	
-			sei
-			lda #<irq1
-			sta $0314
-			lda #>irq1
-			sta $0315
-			lda #$1b
-			sta $d011
-			lda #$80
-			sta $d012
-			lda #$7f
-			sta $dc0d
-			sta $dd0d
-			lda #$81
-			sta $d01a
-			lda $dc0d
-			lda $dd0d
-			asl $d019
-			cli
+			// sei
+			// lda #<irq1
+			// sta $0314
+			// lda #>irq1
+			// sta $0315
+			// lda #$1b
+			// sta $d011
+			// lda #$80
+			// sta $d012
+			// lda #$7f
+			// sta $dc0d
+			// sta $dd0d
+			// lda #$81
+			// sta $d01a
+			// lda $dc0d
+			// lda $dd0d
+			// asl $d019
+			// cli
 			rts
 
 //---------------------------------------------------------
-irq1:  	    asl $d019
-			inc $d020
-			jsr music.play 									// <- Here we get the play address from the sid file
-			dec $d020
-			jmp $ea81
+// irq1:  	    asl $d019
+// 			inc $d020
+// 			jsr music.play 									// <- Here we get the play address from the sid file
+// 			dec $d020
+// 			jmp $ea81
 
 //---------------------------------------------------------
 			*=music.location "Music"

textscroller.asm

@@ -0,0 +1,107 @@
+
+initScroller:	ldx #40				// init color map
+			lda #01
+			sta $dbc0, x
+			dex
+			bpl initScroller+4
+
+			// sei					// set up interrupt
+			// lda #$7f
+			// sta $dc0d			// turn off the CIA interrupts
+			// sta $dd0d
+			// and $d011			// clear high bit of raster line
+			// sta $d011		
+
+			// ldy #00				// trigger on first scan line
+			// sty $d012
+
+			// lda #<noscroll		// load interrupt address
+			// ldx #>noscroll
+			// sta $0314
+			// stx $0315
+
+			// lda #$01 			// enable raster interrupts
+			// sta $d01a
+			// cli
+			rts					// back to BASIC
+
+noscroll:	lda $d016			// default to no scroll on start of screen
+			and #248			// mask register to maintain higher bits
+			sta $d016
+			ldy #242			// trigger scroll on last character row
+			sty $d012
+			lda #<scroll		// load interrupt address
+			ldx #>scroll
+			sta $0314
+			stx $0315
+			inc $d019			// acknowledge interrupt
+			rts
+
+scroll:		lda $d016			// grab scroll register
+			and #248			// mask lower 3 bits
+			adc offset			// apply scroll
+			sta $d016
+
+			dec smooth			// smooth scroll
+			bne continue
+
+			dec offset			// update scroll
+			bpl resetsmooth
+			lda #07				// reset scroll offset
+			sta offset
+
+shiftrow:	ldx #00 			// shift characters to the left
+			lda $07c1, x
+			sta $07c0, x
+			inx
+			cpx #39
+			bne shiftrow+2
+
+			ldx nextchar		// insert next character
+			lda message, x
+			sta $07e7			
+			inx
+			lda message, x
+			cmp #$ff			// loop message
+			bne resetsmooth-3
+			ldx #00
+			stx nextchar
+
+resetsmooth:	ldx #01				// set smoothing
+			stx smooth			
+
+			ldx offset			// update colour map
+			lda colors, x
+			sta	$dbc0
+			lda colors+8, x
+			sta $dbc1
+			lda colors+16, x
+			sta	$dbe6
+			lda colors+24, x
+			sta $dbe7
+
+continue:	ldy #00				// trigger on first scan line
+			sty $d012
+			lda #<noscroll		// load interrupt address
+			ldx #>noscroll
+			sta $0314
+			stx $0315
+			inc $d019			// acknowledge interrupt
+			rts
+
+offset:		.byte 07 			// start at 7 for left scroll
+smooth:		.byte 01
+nextchar:	.byte 00
+//--= WORLDCLASS DEMO - BY ITEMA 1337 HAX0R CREW - FROYA 2020 =--
+message:	.byte 045, 045, 061, 032, 023, 015, 018, 012 
+			.byte 004, 003, 012, 001, 019, 019, 032, 004 
+			.byte 005, 013, 015, 032, 045, 032, 002, 025 
+			.byte 032, 009, 020, 005, 013, 001, 032, 049
+			.byte 051, 051, 055, 032, 008, 001, 024, 048 
+			.byte 018, 032, 003, 018, 005, 023, 032, 045
+			.byte 032, 006, 018, 015, 025, 001, 032, 050 
+			.byte 048, 050, 048, 032, 061, 045, 045, 255
+colors: 	.byte 00, 00, 00, 00, 06, 06, 06, 06
+			.byte 14, 14, 14, 14, 03, 03, 03, 03
+			.byte 03, 03, 03, 03, 14, 14, 14, 14
+			.byte 06, 06, 06, 06, 00, 00, 00, 00