processor 6502
	org  $7ffe
        word $8000	; load address
; cartridge header (http://swut.net/c64cart-howto.html)
        .byte $09, $80, $25, $80
        .byte $c3, $c2, $cd, $38, $30
        .byte $8e, $16, $d0, $20, $a3, $fd, $20
        .byte $50, $fd, $20, $15, $fd, $20, $5b
        .byte $ff, $58
        .byte $ea, $ea, $ea, $ea, $ea, $ea, $ea
        .byte $ea, $ea, $ea, $ea, $ea
; program start
Temp	equ	$00
Start
	sei		; turn off interrupts
	ldy #0
        sty $d020	; reset border color
Loop
        lda Message,y	; load message byte
        beq EOM		; 0 = end of string
        clc
        adc #$c0	; + 192
        sta $400+41,y	; store to screen
        iny
        bne Loop	; next character
EOM
Wait1
	lda $d011
        bmi Wait1	; wait for line < 256
Wait2
	lda $d012	; get current scanline
Wait3
        cmp $d012
        beq Wait3	; wait for scanline to change
        lsr
        lsr
        clc
        adc Temp
        sta $d020	; set border color
	lda $d011	; get status bits
        bpl Wait2	; repeat until line >= 256
	sty $d020	; reset border color
        dec Temp	; scroll colors
	jmp Wait1	; endless loop
Message
	; PETSCII - http://sta.c64.org/cbm64pet.html
	byte "HELLO`WORLDa"
	byte 0