29 Dec
2008
29 Dec
'08
11:52 a.m.
And since some have mentioned it, there was a 3rd party upgrade to the
11/70 which replaced the whole memory system with a few cards in the CPU
box, which turned all memory into cache.
This was by a company called SETASI, and the product was the hypercache.
They actually had two products. HC-70 was the hypercache, and then you
had something called the PEP-70 as well. It appears they could be used
together, but I don't know if one was required for the other, or if they
were related in any way, and if so how.
(SETASI also did other stuff, such as a SCSI adapted for massbus, which
was pretty nice, and usable both on 16-bit and 36-bit machines.)
Johnny
29 Dec
29 Dec
6:51 p.m.
On Mon, Dec 29, 2008 at 6:52 AM, Johnny Billquist <bqt at softjar.se> wrote:
And since some have mentioned it, there was a 3rd
party upgrade to the 11/70
which replaced the whole memory system with a few cards in the CPU box,
which turned all memory into cache.
This was by a company called SETASI, and the product was the hypercache.
They actually had two products. HC-70 was the hypercache, and then you had
something called the PEP-70 as well. It appears they could be used together,
but I don't know if one was required for the other, or if they were related
in any way, and if so how.
Once I got the keyword "PEP-70", I easily found the previously
mentioned install guide. It appears that the products are usable
singly or combined. Since I don't really care about squeezing extra
CPU performance, I wouldn't personally hold out for the hypercache,
but replacing an MK-11 loaded with 16 256K cards with a single card is
enticing.
(SETASI also did other stuff, such as a SCSI adapted
for massbus, which was
pretty nice, and usable both on 16-bit and 36-bit machines.)
Neat. I've never seen any of that - I've only played with real DEC
peripherals on MASSBUS.
-ethan
10:36 p.m.
On Mon, Dec 29, 2008 at 4:54 PM, Alexandre Souza
<alexandre-listas at e-secure.com.br> wrote:
How hard? Not particularly... in this case, I'd use the same SRAMs
that Bob Armstrong did with the SBC6120 RAM disk - JEDEC pinout,
512Kx8. You'd need 4-wide for the data, and 5-wide if you wanted to
not fake the ECC (the real boards are 39-bits wide). There's one free
slot in the 11/70 CPU backplane (where the PEP-70 goes), and as I
think someone (Guy?) pointed out, it only gets power and ground from
the backplane - all the signals come in on ribbon cables from the
cache cards, so a quad-height (or dual-height?) card would be enough.
I don't know the memory cycle time of the 11/70 (or the 11/730 or
11/750), but the MS730AA should be identical to the MS750AA and
identical to what goes in the MK11, unless I'm really mistaken (the
MS730CA and MS750CA 1MB cards are also the same as each other - I've
moved them from machine to machine). The DRAMs in all of these are
ordinary 16-pin DRAMs of late 1970s vintage, so like the 4096 and
4116, AFAIK, but the printset will confirm that (and they happen to be
same chips used in the MS8AA and MS8CA and MS8DJ 16K, 32K and 128K
boards for the PDP-8/a). These are glacially slow by modern
standards, 120ns to 150ns, so I don't think SRAM access times would be
a factor.
You'd need 8 of those chips (or 10 for ECC) to completely fill the
11/70s memory space, wired as two banks of 4 (or 5). That's not much
room, even for DIP parts. I suppose if you wanted to try a
dual-height card, it might be necessary to stay at the quad-height
card size, but with SMT RAM, I don't see why you couldn't go with
dual-height (just remember to get 5V RAMs to simplify things).
That's all fairly trivial stuff to do with the RAM field. With the
quantities involved, buffering isn't a big issue, and neither is
select logic. What I do not know the first thing about, though, is
what sort of logic needs to be there to implement even a fake ECC
scheme, including, probably, CSR registers, etc. Unlike DIMMs in a
PC, PDP-11 memory isn't just a passive field of chips; it's "active"
to various degrees, Bust out the docs for any Unibus memory card and
browse around the schematic - there's lots going on, and not just DRAM
refresh.
I do not know nearly enough to contemplate designing a board to
imitate the entire MK11 and a stack of memory. The memory is the
simple part. The idea of mating a RAM field with a Spartan 3 FPGA
sounds entirely workable, but I wouldn't know how to bring it all
together nor what to stuff in the FPGA to make it all magically work.
I do find the idea enticing. I'm not the guy to make it happen. I
could build one, but someone else will have to design it.
In the meantime, similarly, a 4MB card for the KA730 would be nice -
I know that never existed in real life. If there's a chance of
getting one up to 7MB or 8MB, it would take new memory to try.
-ethan
-ethan
but replacing
an MK-11 loaded with 16 256K cards with a single card is
enticing.
Ethan, how hard it is to create a wire-up (or like) board with some PC
SRAMs? 
10:44 p.m.
I do not know nearly enough to contemplate designing a
board to
imitate the entire MK11 and a stack of memory. The memory is the
simple part. The idea of mating a RAM field with a Spartan 3 FPGA
sounds entirely workable, but I wouldn't know how to bring it all
together nor what to stuff in the FPGA to make it all magically work.
Nor do I, but it would be something interesting :o)
The SBC6120 is a **real nice** SBC, wish I had saved a T-11 (was it?)
processor from many of the arcade boards I saw going to trash...I do not
even know how to operate a PDP, but it would be something fun to learn :o)
Ok, I know the ersatz-11, but this is not hardware... :o)
Alexandre, the hardware lover :D
10:52 p.m.
Alexandre Souza wrote:
The SBC6120 is a **real nice** SBC, wish I had
saved a T-11 (was it?)
processor from many of the arcade boards I saw going to trash...I do not
even know how to operate a PDP, but it would be something fun to learn :o)
I think I asked the question a couple of years ago, about which
"classic" non-typical CPUs turned up in arcade machines. I seem to
recall someone saying that the T-11 was used in Paperboy.
Gordon
30 Dec
30 Dec
2:51 p.m.
I think I asked the question a couple of years ago,
about which
"classic" non-typical CPUs turned up in arcade machines. I seem to
recall someone saying that the T-11 was used in Paperboy.
If I'm not mistaken, paperboy and 720.
Somewhere, in the MAME site or docs, there is a complete list of
processors used in all games
29 Dec
29 Dec
10:54 p.m.
On Mon, 29 Dec 2008, Alexandre Souza wrote:
If you don't have an SBC6120, you can get in on the new run announced a
couple days ago. Bob apparently found some NOS processor chips. See the
sparetimegizmos mailing list for more info.
--
David Griffith
dgriffi at cs.csubak.edu
A: Because it fouls the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing in e-mail?
I do not know
nearly enough to contemplate designing a board to
imitate the entire MK11 and a stack of memory. The memory is the
simple part. The idea of mating a RAM field with a Spartan 3 FPGA
sounds entirely workable, but I wouldn't know how to bring it all
together nor what to stuff in the FPGA to make it all magically work.
Nor do I, but it would be something interesting :o)
The SBC6120 is a **real nice** SBC, wish I had saved a T-11 (was it?)
processor from many of the arcade boards I saw going to trash...I do not even
know how to operate a PDP, but it would be something fun to learn :o)
30 Dec
30 Dec
3:20 p.m.
If you don't have an SBC6120, you can get in on
the new run announced a
couple days ago. Bob apparently found some NOS processor chips. See the
sparetimegizmos mailing list for more info.
Those are good news! Take a look there, but too expensive for a
third-worlder to play at home. If I can find a HD6120 chip around (I've seen
it somewhere...but...WHERE? :oO) I'll build one :o) The PC Board has a very
fair price :oD
BTW, what about a list of what gadget uses these old processors? It
sould be great to find old chips for cheap :oD
29 Dec
29 Dec
11:02 p.m.
On Dec 29, 2008, at 2:44 PM, Alexandre Souza wrote:
If there's enough interest, I'll try for it since I'm doing a unibus
memory board (a multifunction board) with an FPGA for everything but
the memory and interfaces. I'd have to look at the interface from the
cache boards, but I might be tempted to use SSRAMs since they can be
obtained in wide bit widths (36 bits) in a single chip and aren't too
difficult to interface to (timing wise). I know that they come in
512K x 36 since I'm considering that for another project. So that
would only require 2 parts for the entire memory array (4MB). If ECC
were required, there'd be a bit more involved and I'd have to look to
see what was available.
However, I'm swamped with my real job and haven't had a lot of time
(read none) to spend on this stuff. I've already done the schematic
capture for the Unibus interface and level shifters and I'm about
15-20% done coding up the verilog for the FPGA. I've done all of the
high level design, memory timing and unibus address decode. The rest
is the internal interconnect, serial, unibus state machine and
configuration state machine plus the individual unibus devices
(memory, KW11L, ROMs, 2 SLUs).
TTFN - Guy
I do not know
nearly enough to contemplate designing a board to
imitate the entire MK11 and a stack of memory. The memory is the
simple part. The idea of mating a RAM field with a Spartan 3 FPGA
sounds entirely workable, but I wouldn't know how to bring it all
together nor what to stuff in the FPGA to make it all magically work.
Nor do I, but it would be something interesting :o)
30 Dec
30 Dec
12:30 a.m.
On Mon, Dec 29, 2008 at 6:02 PM, Guy Sotomayor <ggs at shiresoft.com> wrote:
If there's enough interest, I'll try for it
since I'm doing a unibus memory
board (a multifunction board) with an FPGA for everything but the memory and
interfaces. I'd have to look at the interface from the cache boards, but I
might be tempted to use SSRAMs since they can be obtained in wide bit widths
(36 bits) in a single chip and aren't too difficult to interface to (timing
wise). I know that they come in 512K x 36 since I'm considering that for
another project. So that would only require 2 parts for the entire memory
array (4MB).
Handy.
If ECC were required, there'd be a bit more
involved and I'd
have to look to see what was available.
My personal thought was that one could get away with simulated ECC
(enough to fool what the OS is expecting) or I do know that one can do
some form of ECC with 36 bits per word - I have an Alpha board that
does it (36-bit-wide 72-pin SIMMs).
However, I'm swamped with my real job and
haven't had a lot of time (read
none) to spend on this stuff.
Understandable.
I've already done the schematic capture for
the Unibus interface and level shifters and I'm about 15-20% done coding up
the verilog for the FPGA. I've done all of the high level design, memory
timing and unibus address decode. The rest is the internal interconnect,
serial, unibus state machine and configuration state machine plus the
individual unibus devices (memory, KW11L, ROMs, 2 SLUs).
Cool.
Speaking only for myself, a modern Unibus board is more interesting
than a board that only works in 11/70s. The number of 11/70s running
in hobbyists' hands is tiny compared to the overall number of lesser
Unibus machines. And since many of those lesser machines might not
have a full load of memory, the impact of changing from old to new is
greater. My 11/70s have full MK11s - the idea of running without an
MK11 is about space (second rack) and power consumption and
maintainability. If I had run across an 11/70 CPU only that had lost
the MK-11 some time back, I might feel differently, but I think the
ratio of 11/70s with no memory to ones that are complete is rather
small.
I look forward to hearing more about, then buying, your universal
memory board. I'm not sure I could afford a modern PEP-70
replacement, let alone two.
-ethan
10:18 a.m.
On Mon, 29 Dec 2008 20:44:17 -0200
"Alexandre Souza" <alexandre-listas at e-secure.com.br> wrote:
The SBC6120 is a **real nice** SBC, wish I had saved a
T-11 (was it?)
The T11 is a PDP-11, the SBC6120 is a PDP-8.
--
tsch??,
Jochen
Homepage: http://www.unixag-kl.fh-kl.de/~jkunz/
7:09 p.m.
The SBC6120 is a **real nice** SBC, wish I had
saved a T-11 (was it?)
processor from many of the arcade boards I saw going to trash...I do not
even know how to operate a PDP, but it would be something fun to learn :o)
A real Unibus PDP11, built from TTL and with a lights-n-switches front
panel is a lot more fun :-)
One unexpected (at least to me) place where the T11 turns up is in the
VT240 terminal. I thought those were relatively easy to find and not much
desired. I know nobofy bid against me when I bought one on E-bay a year or
so back.
-tony
7:43 p.m.
On Dec 30, 2008, at 2:09 PM, Tony Duell wrote:
One unexpected (at least to me) place where the T11
turns up is in the
VT240 terminal. I thought those were relatively easy to find and
not much
desired. I know nobofy bid against me when I bought one on E-bay a
year or
so back.
I dearly love VT240s. I suspect the lack of demand is more a
matter of surplus of supply...there are a LOT of them out there. A
surplus dealer in the Washington DC area whose facility I used to
frequent had quite a few...on three separate occasions he received
shipments of HUNDREDS of them. I grabbed a couple; now in hindsight
I regret not having grabbed more.
-Dave
--
Dave McGuire
Port Charlotte, FL
8:29 p.m.
On Tue, Dec 30, 2008 at 2:09 PM, Tony Duell <ard at p850ug1.demon.co.uk> wrote:
A real Unibus PDP11, built from TTL and with a
lights-n-switches front
panel is a lot more fun :-)
Yep... I still gotta restore a chopped-up 11/20 I rescued, one of
these days. It needs a lot of work, but I think I have +95% of the
parts.
One unexpected (at least to me) place where the T11
turns up is in the
VT240 terminal. I thought those were relatively easy to find and not much
desired. I know nobofy bid against me when I bought one on E-bay a year or
so back.
I've had a VT240 for a while - I liked my VT220 more (lighter,
smaller, and I didn't _need_ the graphics, but they were fun to play
with), but I couldn't argue with the price: I worked for a guy doing
DEC stuff at the time, and he gave me two and said if I got them both
working, I could keep one... a couple of EIA line receivers and power
switches later, I was all set.
-ethan
8:38 p.m.
On Tuesday 30 December 2008, Tony Duell wrote:
One unexpected (at least to me) place where the T11
turns up is in
the VT240 terminal. I thought those were relatively easy to find and
not much desired. I know nobofy bid against me when I bought one on
E-bay a year or so back.
Yep, I've got a few, and I don't think I've paid more than $10 (maybe
$15 with shipping) for any of them. I was thinking about reusing the
T-11 for some sort of project (or figuring out enough of the hardware
to turn it into a minimal "pdp-11".) I thought that it'd be fun to run
RT-11 (or something) on a VT240, and hook another terminal up to it for
a console. :) Unfortunately, other projects, and the probable
difficulty kept me from working much on it.
Pat
--
Purdue University Research Computing --- http://www.rcac.purdue.edu/
The Computer Refuge --- http://computer-refuge.org
11:11 p.m.
Tony Duell wrote:
One unexpected (at least to me) place where the T11 turns up is in the
VT240 terminal. I thought those were relatively easy to find and not much
desired. I know nobofy bid against me when I bought one on E-bay a year or
so back.
They are also on the rqdx3, and there are many more rqdx3 still out
there then rd54 ;-)
5859
days inactive
5860
days old
18 comments
11 participants
participants (11)
-
alexandre-listas＠e-secure.com.br -
ard＠p850ug1.demon.co.uk -
bqt＠softjar.se -
dgriffi＠cs.csubak.edu -
emu＠e-bbes.com -
ethan.dicks＠gmail.com -
ggs＠shiresoft.com -
gordonjcp＠gjcp.net -
jkunz＠unixag-kl.fh-kl.de -
mcguire＠neurotica.com -
pat＠computer-refuge.org