On 10/9/23 05:50, Johnny Billquist wrote:
>>> Well. I had massbus drives many meters from the main cabinets. Not sure
>>> I'd trust flat cables of that length...
>>
>> The Fujitsu M2351A product specification says the limit for the A cable
>> is 100 feet and the B cable is 50 feet.
>
> Longer than I expected.

Differential signaling.

-Dave

--
Dave McGuire, President/Curator
Large Scale Systems Museum
New Kensington, PA

On 10/9/23 04:03, gah4 wrote:
> Sun used round cables for SMD, at least outside boxes.

They did that so that they could use more economical connectors for
external cabling, DC37 and DB25 connectors.

> They might have been ribbon cables inside.

That is correct.

That memory was refreshed for me recently when I built out a
Sun-3/280 at the museum, running from a pair of 892MB SMD drives. And
an FPA! Such a nice system. I ran the heck out of those back in the
day, and they seem just as nice now.

-Dave

--
Dave McGuire, President/Curator
Large Scale Systems Museum
New Kensington, PA

On Monday, October 9, 2023 at 9:42:13 AM UTC-7, Dave McGuire wrote:

(snip)

> That memory was refreshed for me recently when I built out a
> Sun-3/280 at the museum, running from a pair of 892MB SMD drives. And
> an FPA! Such a nice system. I ran the heck out of those back in the
> day, and they seem just as nice now.

Place I used to work had a Sun 3/260.

At one point, we found that used 4/260 CPU boards were low priced,
and so upgraded the CPU board. I should have kept the old board,
but didn't think about it at the right time.

Not so many years ago, though, I found out about the Sun 3/E.

That is a 6U VME board, much smaller than the 9U boards for
the 3/260 and 4/260 CPU. Also, a SCSI/Ethernet 6U board,
and a VME backplane and power supply. Instead of finding
a SCSI disk, I got it running diskless. That came out late
in the Sun 3 days, meant for embedded systems.

Later, I found a 6U Sun 4 board, but didn't get around to
configuring that one.

The backplane and power supply had two independent
sets of three slots. I could run both a Sun 3 and Sun 4
system at the same time.