23 Apr
2026
23 Apr
'26
7:03 a.m.
On Thu, Apr 23, 2026 at 4:46 AM Jim Bender via cctalk
<cctalk(a)classiccmp.org> wrote:
Does anybody here still use Massbus?
Or have a Massbus system you’d like to run, but the idea of dealing with
washing-machine disk drives is a bit less appealing these days?
I have a DR750 in the VAX-11/750 I saved from work 30 years ago - we
used it for a TU78 and we had non-MASSBUS storage (Unibus and a
Systems Industries 9400 on a CMI card that was next to the DR750). I
also have at least one 11/70 that could use MASSBUS devices.
Since Mesa 5I22 cards are now pretty much
unobtainium...
The result is a redesigned D/R board that
accepts a Terasic DE10-Nano directly.
I'm familiar with the DE10 series. I have a couple of DE10-Lite
boards for RL02 emulation. Excellent choice.
If anyone here is still actively using Massbus, has
experience with the
original LCM project, or just has relevant war stories, comments, warnings, or
encouragement, I would be glad to hear them.
I have System Adminstrator-level experience with MASSBUS from the
1980s (connecting and using but not repairing), and no experience with
the LCM project. I can offer encouragement though, and in the far
future, I can offer up a possible test example in the way of an 11/750
with DR750 (it would need to be cleaned and tested first - hasn't been
powered on in many years due to a lack of a 30A socket where it's at).
I would also be happy to avoid the MASSBUS cabling issue by connecting
an emulator right to the 11/750 backplane with short or medium length
40-pin cables (the usual arrangement is short flat cables that go from
the backplane to a standard MASSBUS ZIF connector on the I/O buikhead,
then a fat round cable to the first device). I have at least one
original round MASSBUS cable but if there's no reason to pile it up
behind the machine, so much the better.
I guess that also depends on one's physical arrangement, if it's going
to be CPU + Emulator only or CPU + emulator + real MASSBUS devices
further down the chain.
In my case, I'd only ever have that 11/750 or an 11/70 to worry about,
but this device would also be great for someone with a KS10.
-ethan