View Single Post
Old 14 August 2012, 22:14   #29
Wepl
Moderator
 
Wepl's Avatar
 
Join Date: Nov 2001
Location: Germany
Posts: 869
Quote:
Originally Posted by Asman View Post
Just for clarification. About byte read from custom register ($dff005). If I understand correctly below code
Code:
wait_vb_2
.1	btst	#0,(_custom+vposr+1)
	bne	.1
.2	btst	#0,(_custom+vposr+1)
	beq	.2
	rts
can be changed to (more legal)
Code:
wait_vb_2
	moveq	#1,d0
	lea	(_custom+vposr),a0
.1	move.w	(a0),d1
	and.w	d0,d1
	bne	.1
.2	move.w	(a0),d1
	and.w	d0,d1
	beq	.2
	rts
Any comments are welcome especially If I am wrong.
ok, but what should be the advantage of this?
Wepl is offline  
 
Page generated in 0.04416 seconds with 11 queries