Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!cs.utexas.edu!uunet!mcvax!ukc!axion!iwarner
From: iwarner@zaphod.axion.bt.co.uk (Ivan Warner,G44 SSTF,6632,)
Newsgroups: comp.sys.atari.8bit
Subject: Re: DataQue Turbo-816 Speed
Message-ID: <1711@zaphod.axion.bt.co.uk>
Date: 5 Jun 89 13:19:35 GMT
References: <3753@udccvax1.acs.udel.EDU>
Sender: news@axion.bt.co.uk
Reply-To: iwarner@zaphod.axion.bt.co.uk
Lines: 46

From article <3753@udccvax1.acs.udel.EDU>, by gdtltr@vax1.acs.udel.EDU (Gary D Duzan):
 
>    Please do not publish the following information anywhere outside USENET
> (i.e. newsletters or pay systems. I guess BBS's are ok, though.)
>    I had a chat with Chuck Steinman on the DataQue support BBS, and he was
> very helpful in answering my questions. It seems that the 65816 processor
> used in the Turbo 816 is rated for 5 Mhz, though it appears it would probably
> handle 8 Mhz. However, due to restrictions placed by the RAM on the
> motherboard and some of the support chips (Pokey was mentioned), the Turbo
> will be running at the normal 1.79 Mhz. { This may sound very limiting, but the
> 65816 in native mode will still be a good bit faster due to its ability to
> handle 16 bit data chunks. More advanced features of the 65816 help as well
> (there are two commands to move blocks of memory.) } DataQue is working on
> this problem and will probably release an accelerator board in the future to
> increase the speed closer to the chip's limit.
>    (Info in {} above is my own, not Chuck's.)
 
 
> 					Gary Duzan
> 					Time  Lord
> 				    Third Regeneration
> 				 Atari Enthusiast Extreme


	Could you post some more information about the DataQue Turbo-816,
as this is the first I've heard of it.

	From what you say, can I assume that it is a board that runs
standard Atari/6502 software, but using the 65816 instead of a 6502 ??

	I am interested because the final year project of my degree was
to add a 65816 2nd processor to an Atari 800XL. I ran the 65816 at 2.5MHz,
as I was not constrained by the graphics chips (Antic,GTIA) which require
the Atari to run at 1.79MHz. This meant that graphics progs would not work
unmodified, but stuff like BASIC, and Assemblers would.
The software ran twice as fast on the 65816 as on the 800XL (because the
6502 on the 800XL is slowed down by DMA performed by Antic).

	I connected the two together using the 800XL's parallel port. Any
I/O operations (such as screen, keyboard and disc accesses) were passed
across the parallel port to be handled by the 800XL. Thus the 65816
took over the role as main processor, and the 800XL was an intelligent
terminal to it.


		Ivan Warner