Create 6502-assembly.s

#/6502-assembly.s

@@ -0,0 +1,22 @@
+; goodbyeworld.s for C= 8-bit machines, ca65 assembler format.
+; String printing limited to strings of 256 characters or less.
+ 
+a_cr	= $0d		; Carriage return.
+bsout	= $ffd2		; KERNAL ROM, output a character to current device.
+ 
+	.code
+ 
+	ldx #0		; Starting index 0 in X register.
+printnext:
+	lda text,x	; Get character from string.
+	beq done	; If we read a 0 we're done.
+	jsr bsout	; Output character. 
+	inx		; Increment index to next character.
+	bne printnext	; Repeat if index doesn't overflow to 0.
+done:
+	rts		; Return from subroutine.
+ 
+	.rodata
+ 
+text:
+	.byte	"Hello world!", a_cr, 0