OT: A call to arms (sort of) - test-drb@ccmp.vtda.org

5 Jul 1999

It's true there are  lots of VME boards around.  There just aren't many
cheap ones.

The connector doesn't define the bus standard being used.  TI used a 100-pin
edge connector for some of thir 99xx development systems.  Multibus-II and
VME look pretty similar.  NuBUS, as Tony pointed out, certainly used the DIN
connector and used a form factor not too different from the ISA.

As I said before, you could use a modified version of whatever bus you
almost like, then call it whatever you like, but not what it specifically
isn't.

Dick

-----Original Message-----
From: CLASSICCMP(a)trailing-edge.com &lt;CLASSICCMP(a)trailing-edge.com&gt;
To: Discussion re-collecting of classic computers
&lt;classiccmp(a)u.washington.edu&gt;
Date: Monday, July 05, 1999 7:43 AM
Subject: Re: OT: A call to arms (sort of)

...
 >On Sun, 4 Jul 1999, Richard Erlacher wrote:
>>If I were using the DIN connectors, I'd get a standard out, read and
>>understand it, and then use it, calling it VME, its rightful name.
>>Unfortunately, I'd not be able to get a two-port serial board or a LAN
board
...
  >for VME
from the local thrift store. 
 I don't get it...are you saying that the
connector somehow determines the
bus? An bus could in theory be compatible with ISA and use some other
connector, and still be ISA for the most part. 
I suspect that it's just Dick on one of his rants these days.  VME
boards are extremely plentiful these days, as are prototyping boards
with the connectors.

Of course, there are cases where the same connector was used on two
different busses.  The connector and card size of the Motorola EXORcisor
system is remarkably similar to the S-100 bus (to the point where I've
actually mistaken one for the other until I got up close and looked.)
And the 44-conductor-edge-connector design has been used in so many
instruments and machines that it is completely "generic".

There are *many* ISA-compatible busses in use in the embedded systems
world that use "different" connectors.  Some of these are proprietary,
meaning they're only used by one company, others are much more widespread
(like the PC/104 bus).  OK, there are some drive differenences between
PC/104 and ISA, but that's an "improvement" for the application.  See
http://www.pc104.com/ for a PC/104 FAQ.  PC/104 was originated by Ampro,
a maker of classic computers, so I feel justified in mentioning it here :-).
...

--
 Tim Shoppa                        Email: shoppa(a)trailing-edge.com
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