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From: mt87692@lehtori.tut.fi (Mikko Tsokkinen)
Newsgroups: comp.sys.amiga.programmer
Subject: Not working example in HRM 1.3!
Message-ID: <MT87692.91Feb27214136@lehtori.tut.fi>
Date: 27 Feb 91 20:41:36 GMT
Sender: mt87692@cc.tut.fi (Mikko Tsokkinen)
Distribution: comp
Organization: Tampere University of Technology
Lines: 28



 Hello,

 I was programming yesterday evening and noticed a bug in hardware reference
manual. About page 29 in copper section there is a example program making
interrups every 16 scan lines, however it does not work.

code is something like this

dc.w	$0f01,$8f00	; wait for low 4 bits to become true
signal processor (dont remember the opcode)
dc.w	$00e3,$00fe	; wait for line to finish
	   ^^ Now this is wrong, it should be e1. Actually this is proposed
	      to wait for scan line to end but actually it waits for position
	      $8100 . The copper never reaches $e2 in horizontal direction
	      (at least not in my amiga :-) when running in lores noninterlaced
	      pal mode. This information can be by the way read from the blitter
	      section DMA timing diagram.
... rest of the code removed ...

 Now you don't have to waste your time with this nonworking example (very typical
in computer manuals in general:-)

BTW my setup is 1MEG pal agnus, 1M CHIP, 8M FAST etc.

 MIT
-- 
Bubble Bobble