[comp.sys.atari.st.tech] TT VME Bus

mts10271@uxa.cso.uiuc.edu (Michael T Stepniczka) (05/16/91)

	I was wondering if it is possible to add more than one card to
the TT's VME slot.  If not, is there any way to add stronger drivers
or an external card cage?  (I want to buy a TT at the end of the summer
and plan to design a card for it in one of my lab classes. I hope it's
more expandable than previous Atari systems! :-))
	Thanks for any info!

					Michael Stepniczka
					mts10271@uxa.cso.uiuc.edu

P.S.	Thanks to those who replied to my rsrc_gaddr() posting- it's all
	clear now.

carter@cat23.cs.wisc.edu (Gregory Carter) (05/16/91)

In article <1991May16.065921.26031@ux1.cso.uiuc.edu> mts10271@uxa.cso.uiuc.edu (Michael T Stepniczka) writes:
>
>	I was wondering if it is possible to add more than one card to
>the TT's VME slot.  If not, is there any way to add stronger drivers
>or an external card cage?  (I want to buy a TT at the end of the summer
>and plan to design a card for it in one of my lab classes. I hope it's
>more expandable than previous Atari systems! :-))
>	Thanks for any info!
>
>					Michael Stepniczka
>					mts10271@uxa.cso.uiuc.edu
>
>P.S.	Thanks to those who replied to my rsrc_gaddr() posting- it's all
>	clear now.

I made a rather large technical post on the VME capabilities of the MEGA STE
and TT machine a while back.

However, a german company makes an extended card cage for the TT/MEGA STE
and VME cards for graphics and cpu accelerators.  It was shown at the last
CeBit show, I think.

So yes, you can have more than one card with the addition of an external
cage.

However, don't expect to see anything like that here in the US. :(

--Gregory

baffoni@aludra.usc.edu (Juxtaposer) (05/17/91)

In article <1991May16.163752.24994@daffy.cs.wisc.edu> carter@cat23.cs.wisc.edu (Gregory Carter) writes:
<stuff deleted>
>
>However, a german company makes an extended card cage for the TT/MEGA STE
>and VME cards for graphics and cpu accelerators.  It was shown at the last
>CeBit show, I think.

	Is it possible/have they already made  an accelerator card that  uses
the buslines available on the VME/Atari (TT/mega)bus slots?  Like for instance 
a 68040 board that takes over the machine (I've seen stuff like that for the 
Mac and thought you might be able to do the same thing) and delegates the on
board cpu as an I/O handler (and other CPU wasting projects).  However, I could
be mistaken (_I_ don't use 'em, let alone build 'em), but would something like
that be possible for the TT?  Dave Small has already shown that it's possible
for the ST...:)

>However, don't expect to see anything like that here in the US. :(
<sigh>
>
>--Gregory

-Mike

apratt@atari.UUCP (Allan Pratt) (05/21/91)

baffoni@aludra.usc.edu (Juxtaposer) writes:
>	Is it possible [to make]  an accelerator card that  uses
>the buslines available on the VME/Atari (TT/mega)bus slots?  Like for instance 
>a 68040 board that takes over the machine and delegates the on
>board cpu as an I/O handler ... ?

No, it's not, because the things that can go on the VME bus in the TT can't
be bus masters.  The TT's VME bus is slave-only, meaning the motherboard
can instigate an access to the VME board, but not the other way around. It
is not unreasonable to suppose that future Atari machines may have
full-blown VME where the VME boards can be bus masters, and then you could
do this.

>Dave Small has already shown that it's possible
>for the ST...:)

No, he shows that it's possible to wire a 68030 into the ST.  I don't know
how he tells the 68000 to go to sleep; maybe you have to cut the whole
thing loose, maybe you just have to cut a few traces (like power and
ground :-) to get it out of the circuit.

============================================
Opinions expressed above do not necessarily	-- Allan Pratt, Atari Corp.
reflect those of Atari Corp. or anyone else.	  ...ames!atari!apratt