[rescue] Sun 3/80 Schematics

[Chris Hanson]

On Oct 16, 2019, at 10:22 AM, Bill D <dorsey at lila.com> wrote:
>
> Appreciate the suggestion.  Do you have any pointers to available VME stuff
> along these lines I could look at?  Of course I would prefer to use SunOS,
> but older versions of NetBSD are also perfectly acceptable as well.

Sure! I'd start by looking at the CPU cards that NetBSD supports:

http://wiki.netbsd.org/ports/mvme68k/

Obviously more boards have been supported over time so using an older NetBSD
might not be an option with some boards. You'd probably be best off with an
MVME147 (68030) or MVME167 (68040) if you want to use an older NetBSD since
they appear to be well-supported by 1.4 and later. You should be able to find
a '147 or '167 on eBay in the US$100 range with a reasonable amount of
piggybacked memory (32MB) and both models have basic "server" I/O built in
(serial, parallel, SCSI, Ethernet). You can also get just the CPU card and add
the memory separately which might make it easier to get a decent CPU
inexpensively.

There's also the MVME172 if you want a 68060 but the least expensive I've seen
those are several hundred dollars. Once nice thing about the VME gear,
however, is that you can set things up with a '147 or '167 and then swap in a
'172 later... Or even an 88K or PowerPC board!

You'll also need a backplane to plug the card into, to provide it power and
VME I/O. You don't actually need any other cards in the system, but you will
need a backplane with both P1 and P2 connectors, including a *rear* P2
connector, because the CPU card only has the I/O peripherals on it, not the
connectors; those are all sent to the P2 connector. Your backplane will of
course also need a power supply, and to be put in an enclosure.

Finally you'll need a "transition" board and I/O port adapter; you plug the
board into the backside P2 connector, opposite where the CPU card is plugged
in, and it has a cable to a set of I/O ports. The transition cards used by the
'147, '167, and '172 CPU cards are referred to as MVME172X because there are
several different varieties. You should be able to get an MVME172M that has
four serial ports, one parallel port, full-size Centronics SCSI, and AUI
Ethernet for around US$100.

So here's an MVME167 on eBay for US$100:
https://www.ebay.com/itm/192437770699

Here's an MVME712M transition board, unfortunately **without** the necessary
P2 adapter and cabling: https://www.ebay.com/itm/113228349266

The MVME712M's P2 adapter is Motorola part 3496B01A, the cabling is simple and
described in the manual: https://www.ebay.com/itm/143393321621

Or you can buy the 64-conductor ribbon cable between the 712M and P2 adapter
if you don't want to make one: https://www.ebay.com/itm/182382572916 (The
other cable needed is a 50-pin internal SCSI ribbon cable which I suspect you
have a bunch of.)

Here's a full enclosure that contains a three-slot VME backplane and a power
supply: https://www.ebay.com/itm/392239338855

And here's a bigger (8-slot) chassis & backplane only, you'd have to find your
own power supply: https://www.ebay.com/itm/250978115365

For my own 88K system, I have a five-slot version of the full enclosure and
it's light enough to lift with one hand with a couple boards installed, while
also not being flimsy.

  -- Chris