Re: MASSBUS disk emulator (Was: Unibus controller for MFM disks)

2016-10-19 Thread Noel Chiappa
> From: Rich Alderson

> Yes, the d/r card is strictly level conversion, and the microcode in
> the Xilinx does all the Massbus protocol.

So if you don't mind continuing to indulge my curiousity (thanks for all the
indulgence so far :-), is the D/R card a daughtercard that mounts on the Mesa
(my guess)?

Noel


Re: 2020 Power consumption [Was: Re: MASSBUS disk emulator (Was: Unibus controller for MFM disks)]

2016-10-19 Thread Mike Ross
On Wed, Oct 19, 2016 at 7:44 PM, Pontus Pihlgren  wrote:
> On Tue, Oct 18, 2016 at 06:26:06PM +, Rich Alderson wrote:
>>
>> There have been 2 generations of Massbus Disk Emulator (MDE) at LCM.  The
>> one of which people have seen pictures was the first generation, created
>> when there were only 2 people working on the collection which became the
>> museum years later.
>>
>
> Ah, thanks for clarifying :)
>
> Somewhat related, how much power does a 2020 draw on average?
>
> /P

Bye some enormous coincidence I was just looking through some DEC
pdp-10 brochures I have.

DEC advertised the 2020 as drawing no more power that a hairdryer; the
quoted figure was 1400w as I recall.

Mike

http://www.corestore.org
'No greater love hath a man than he lay down his life for his brother.
Not for millions, not for glory, not for fame.
For one person, in the dark, where no one will ever know or see.'


Re: 2020 Power consumption [Was: Re: MASSBUS disk emulator (Was: Unibus controller for MFM disks)]

2016-10-19 Thread Paul Anderson
That should be in the site prep documents, or the installing documentation.

On Wed, Oct 19, 2016 at 1:44 AM, Pontus Pihlgren 
wrote:

> On Tue, Oct 18, 2016 at 06:26:06PM +, Rich Alderson wrote:
> >
> > There have been 2 generations of Massbus Disk Emulator (MDE) at LCM.  The
> > one of which people have seen pictures was the first generation, created
> > when there were only 2 people working on the collection which became the
> > museum years later.
> >
>
> Ah, thanks for clarifying :)
>
> Somewhat related, how much power does a 2020 draw on average?
>
> /P
>


2020 Power consumption [Was: Re: MASSBUS disk emulator (Was: Unibus controller for MFM disks)]

2016-10-19 Thread Pontus Pihlgren
On Tue, Oct 18, 2016 at 06:26:06PM +, Rich Alderson wrote:
>
> There have been 2 generations of Massbus Disk Emulator (MDE) at LCM.  The
> one of which people have seen pictures was the first generation, created
> when there were only 2 people working on the collection which became the
> museum years later.
> 

Ah, thanks for clarifying :)

Somewhat related, how much power does a 2020 draw on average?

/P


RE: MASSBUS disk emulator (Was: Unibus controller for MFM disks)

2016-10-18 Thread Rich Alderson
From: Noel Chiappa
Sent: Tuesday, October 18, 2016 11:51 AM

>> From: Rich Alderson

>> Data was transferred via FTP over a 100baseT crossover cable connected
>> to a Slackware server; the Rabbit was able to keep up with 4 drives at
>> this speed

> Were the bits actually stored on the Slackware server, or was it just used
> to put bits on the 'drive' to start with? If the latter, what were the
> actual bits stored on? (I know, not that relevant, since this is the prior
> rev, but I'm curious.)

Stored on a big honking JBOD array (set up as RAID 5 in Linux), since an
RP06 stored as described is nigh on 900MB, and served up on that FTP link
from Slackware.

>> a Mesa 5i22 Anything I/O card (includes a Xilinx Spartan-III FPGA) that
>> plugs directly into the PCI bus in a server-class X86-64 box, and used
>> a revision of a separate driver/receiver card designed for MDE 1.0 to
>> connect to the Massbus

> Let me make sure I understand this; was there some sort of cable or
> somehow a connection from the Mesa 5i22 directly to the driver/receiver
> card, which was purely 'level conversion', with the Mesa doing the
> 'protocol' on the MASSBUS?  (I.e. they didn't communicate over the PCI
> bus?)

Yes, the d/r card is strictly level conversion, and the microcode in the
Xilinx does all the Massbus protocol.

>> a control program for the PC side which runs under Windows 2008/2012
>> Server.

> So the actual bits are stored on something (disk?) controlled by the PC?

Again using RAID 5 arrays on the PC servers, but PCI makes it a lot faster
than Ethernet.

Rich


Rich Alderson
Vintage Computing Sr. Systems Engineer
Living Computer Museum
2245 1st Avenue S
Seattle, WA 98134

mailto:ri...@livingcomputermuseum.org

http://www.LivingComputerMuseum.org/


Re: MASSBUS disk emulator (Was: Unibus controller for MFM disks)

2016-10-18 Thread Ethan Dicks
On Tue, Oct 18, 2016 at 11:33 AM, Ethan Dicks  wrote:
> I would consider one for my VAX/11-750 since Unibus disk emulation
> solutions aren't plentiful (but I think I'd have to get a DR750
> (L0014) first).

Correction: RH750 (L0007).  The DR750 is a CMI-bus "interprocessor interface".

-ethan


Re: MASSBUS disk emulator (Was: Unibus controller for MFM disks)

2016-10-18 Thread Ethan Dicks
On Tue, Oct 18, 2016 at 9:39 AM, Noel Chiappa  wrote:
> > From: Paul Birkel
>
> > Maybe there are three ribbon cables back there
>
> We _definitely_ need to put these things in 'production'.

I would consider one for my VAX/11-750 since Unibus disk emulation
solutions aren't plentiful (but I think I'd have to get a DR750
(L0014) first).

-ethan


Re: MASSBUS disk emulator (Was: Unibus controller for MFM disks)

2016-10-18 Thread Noel Chiappa
> From: Paul Birkel

> Maybe there are three ribbon cables back there

Sure looks like it, and running to a standard MASSBUS connector, to boot.
(Not that I have any use for the latter - absolutely no MASSBUS cables at
all. But one could just run flat cables from this, to one's RH11/RH70.)

I don't see a second MASSBUS connector, wonder what they do about
termination? Maybe it's onboard? So I guess one could only have one
of these things per MASSBUS port? Not really a problem, of course! ;-)

We _definitely_ need to put these things in 'production'.

Noel


RE: MASSBUS disk emulator (Was: Unibus controller for MFM disks)

2016-10-18 Thread Paul Birkel
-Original Message-
From: cctalk [mailto:cctalk-boun...@classiccmp.org] On Behalf Of Pontus
Pihlgren
Sent: Tuesday, October 18, 2016 1:58 AM
To: General Discussion: On-Topic and Off-Topic Posts
Cc: j...@mercury.lcs.mit.edu
Subject: Re: MASSBUS disk emulator (Was: Unibus controller for MFM disks)

On Mon, Oct 17, 2016 at 10:20:58PM -0400, Noel Chiappa wrote:
> > From: Ian S. King
> 
> >> Does anyone know anything about the status of the plans to
open-source
> >> it?
> 
> > I've made some inquries, stay tuned
> 
> OK, thanks!
> 
> >> Can you briefly describe what it was? 
> 
> I'm still curious about what it was: was it a stand-alone board with a 
> separate power supply, or did it plug into some sort of backplane? Did 
> it use something like SD cards for storage? And what was the MASSBUS 
> connection
> like: a set of 3 Berg headers into which one plugged the flat cables, 
> or was there some oddball connector that wound up connected to a 
> standard MASSBUS connector?
> 
>   Noel

I recall seing a picture of it long ago in someones online album. It was a
separate 19 inch box a few RUs high with at least one pcb and a jumble of
wires :) Obviously in some sort of development stage and I'm not sure it was
working at that point.

I think it might even be the compaq rackbox shown here:

http://www.panix.com/~alderson/LivingComputerMuseum/07_Storage_comparison_in
_open_space.jpg

Of course this is just speculation :)

/P

--

Maybe there are three ribbon cables back there 

What is the big white disk (platters plus heads?) near the front end of the
table?

-
paul



Re: MASSBUS disk emulator (Was: Unibus controller for MFM disks)

2016-10-17 Thread Ian S. King
I've made some inquries, stay tuned

On Mon, Oct 17, 2016 at 1:09 PM, Pontus Pihlgren 
wrote:

> On Mon, Oct 17, 2016 at 12:16:10PM -0400, Noel Chiappa wrote:
> > > From: Ian S. King
> >
> > > When I left in 2014, LCM's Massbus disk emulator was working quite
> well
> > > indeed, and was running in 'production' ... ISTR the plan was
> always to
> > > open-source the hardware and firmware, too.
> >
> > I'm interested in this (as I suspect are lots of other people with
> machines
> > that can use MASSBUS disks). Can you briefly describe what it was? Does
> > anyone know anything about the status of the plans to open-source it?
> >
> >   Noel
>
>
> Yes! While I intend to get my Massbus disks running. An emulator would
> be a great stepping stone.
>
> /P
>



-- 
Ian S. King, MSIS, MSCS, Ph.D. Candidate
The Information School 
Dissertation: "Why the Conversation Mattered: Constructing a Sociotechnical
Narrative Through a Design Lens

Archivist, Voices From the Rwanda Tribunal 
Value Sensitive Design Research Lab 

University of Washington

There is an old Vulcan saying: "Only Nixon could go to China."


Re: MASSBUS disk emulator (Was: Unibus controller for MFM disks)

2016-10-17 Thread Pontus Pihlgren
On Mon, Oct 17, 2016 at 12:16:10PM -0400, Noel Chiappa wrote:
> > From: Ian S. King
> 
> > When I left in 2014, LCM's Massbus disk emulator was working quite well
> > indeed, and was running in 'production' ... ISTR the plan was always to
> > open-source the hardware and firmware, too.
> 
> I'm interested in this (as I suspect are lots of other people with machines
> that can use MASSBUS disks). Can you briefly describe what it was? Does
> anyone know anything about the status of the plans to open-source it?
> 
>   Noel


Yes! While I intend to get my Massbus disks running. An emulator would 
be a great stepping stone.

/P