Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!helios!bcm!dimacs.rutgers.edu!seismo!uunet!cbmvax!ken From: ken@cbmvax.commodore.com (Ken Farinsky - CATS) Newsgroups: comp.sys.amiga.programmer Subject: Re: Not working example in HRM 1.3! Message-ID: <19396@cbmvax.commodore.com> Date: 1 Mar 91 21:29:04 GMT References: Reply-To: ken@cbmvax.commodore.com (Ken Farinsky - CATS) Distribution: comp Organization: Commodore, West Chester, PA Lines: 27 In article mt87692@lehtori.tut.fi (Mikko Tsokkinen) writes: > 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 ... Well, you're half right and we're half right. As far as I know, this code was tested and works on an NTSC Amiga. However, talking with the author, your answer sounds right for a PAL machine. We'll look into this for the next rev of the hardware manual. -- -- Ken Farinsky - CATS - (215) 431-9421 - Commodore Business Machines uucp: ken@cbmvax.commodore.com or ...{uunet,rutgers}!cbmvax!ken bix: kfarinsky