;==========
	; flip page
	;==========
flip_page:
	lda	DRAW_PAGE
	beq	draw_page2
draw_page1:
	bit	PAGE2
	lda	#0

	beq	done_flip

draw_page2:
	bit	PAGE1
	lda	#$4

done_flip:
	sta	DRAW_PAGE

	rts