Hello 6502 Assembly

After many false starts (since age 12), I've finally managed to compile and run a machine language program on my Commodore 64. The code below is in ACME assembly language and displays the "Hello World!" in the middle of the screen. Nothing ground breaking, but it's a required first step to verify that I have all my tools setup and working.

	!cpu 6502
	!to "build/hello.prg",cbm
	* = $0801 ; BASIC starts at #2049
	!byte $0d,$08,$dc,$07,$9e,$20,$34,$39 ; BASIC to load $c000
	!byte $31,$35,$32,$00,$00,$00 ; inserts BASIC line: 2012 SYS 49152
	* = $c000 ; start address for 6502 code
	JSR $E544
	loop jsr init_text ; write line of text
	jmp loop ; infinite loop
	message !scr " hello world! " ;40 cols of text
	init_text ldx #$00 ; init X-Register with $00
	loop_text lda message,x ; read characters from message text...
	sta $0590,x ; ...and place it into screen screen memory
	inx ; increment to next character
	cpx #$28 ; false if != 40
	bne loop_text ; loop if false
	rts

view raw hello.asm hosted with ❤ by GitHub

Anyone looking to cross-develop for the Commodore 64 on OS X should have a look at Dust. Now, let's see if I can make this thing beep...