; print "Hello, world" on teletype output
	; using device I/O instructions
	; DG Nova/RDOS

	.titl hello
	.nrel

start:	
dochar:	lda 0,@pmsg	; load ac0 with next word,
	mov# 0,0,snr	; test ac0; skip if nonzero
	  jmp done
	jsr putc	; output first char of word
	movs 0,0	; swap bytes
	jsr putc	; output second char of word
	isz pmsg	; point to next word
	jmp dochar	; go around again

done:	.systm
	.rtn

putc:	skpbz tto	; is tty busy?
	  jmp .-1	; loop until not busy
	doas 0,tto	; output char in ac0
	jmp 0,3		; return from subroutine

pmsg:	.+1
	; note bytes are packed right-to-left by default
	.txt /Hello, world.<15><12>/ ; that's CR, LF
	0 ; flag word to end string
	
	.end start