Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!cs.utexas.edu!swrinde!kent
From: kent@swrinde.nde.swri.edu (Kent D. Polk)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Real World Amigas?
Message-ID: <17837@swrinde.nde.swri.edu>
Date: 28 Jun 89 17:34:09 GMT
References: <3182@shlump.dec.com>
Reply-To: kent@swrinde.UUCP (Kent D. Polk)
Organization: Southwest Research Institute, San Antonio, Texas
Lines: 54

In article <3182@shlump.dec.com> balzer@frambo.dec.com (Christian Balzer) writes:
>>(Q: about ASDG GPIB Board by me)
>To my greatest surprise I do have such info. The ASDG TwinX/GPIB board
>will NOT support DMA. However you can have the DMA request trigger an
>interrupt.

Hmmm, the product sheet from ASDG indicates a Programmed I/O rate of 70
Kbytes/Second(Typ.) and a DMA I/O rate of 300 Kbytes/Second(Typ.).
Also, indicates a SBX Compliance of "D8 DMA (Eight Bit Module With DMA
Support)". Sounds to me like the iSBX module supports DMA ??

>>Q: ASDG TwinX boards: Since I haven't tried to access custom hardware
>>the system, does ASDG provide software to access TwinX modules?  Can
>>one purchase driver source code?
>Dunno, you might wanna ask Aaron Avery (aaron@madnix.UUCP) or even
>Perry K. himself. ASDG sells you a driver (GPIB.library) with the
>stuff, though.

What kind of functions are provided?  I still haven't gotten around to
writing a letter request. I kinda was hoping they would respond to my
telephone and email requests.

>>Q: What modes of access to the PC bus are available from the Amiga
>>side? Do I have to involve the 80xx.x in the process, or can I read the
>>AT bus directly?
>
>Nope, the AT bus only shares the power with the rest of the Amiga. You
>must either use a CBM Bridgeboard or wait for that dumb but fast and
>cheap connection bridge that was proposed here some months ago.
>But with your knowledge and resources a "dumb" bridge should be nooo
>problem. (Thus spoke the softhead and quickly fleed. :-)

I have trouble believing it would be easy since the PC boards don't
expect a synchronous bus & one would have to account for board timing
problems with the interface.  Actually, if the project comes up, I
might have our hardware guys take a look at such. Looks like I ought to
start collecting the information.

On the other hand, having a 80xx out there pre-processing the data has
it's advantages also. I've done this type of stuff on a PC - utilizing
8088's on peripheral boards with shared buffers for commands/data to be
exchanged between the processors. Kind of a cludge getting things
started up though. Does the new BridgeBoard software have adequate
support for inter-system communications such as this? Is it fast?

Thanks,

=======================================================
       Kent Polk - Southwest Research Institute
 {cs.utexas.edu, gatech!petro sun!texsun}!swrinde!kent
              kent@swrinde.nde.swri.edu
-------------------------------------------------------
       "Anything worth doing is worth overdoing"
=======================================================