>Megan wrote:
>> well put... I've yet to find a compiler which can produce code which
>> could not then be further optimized in some way by a person well
>> versed in that machine's architecture...
>
>Yes, but if you paid attention to the original claim, you would see that
>I asserted that it was true for horizontal microcode with large amounts
>of data dependency. This is *very* different than trying to compile C
>(or Pascal, or Bliss, or whatever) for a typical architecture (which more
>closely resembles vertical microcode).
>
>One of the systems I microcoded had 512 words of control store (of about
>72 bits each), and running my microprogram source code through the compiler
>produced 514 words of microinstructions. With about two weeks of
>concentrated effort, I was able to eventually squeeze out two
>microinstructions. Total development time: 6 weeks.
>
>If I had tried to write all of the microcode in "assembly", it would have
taken
>me longer to write, and it probably would have been *bigger* on the first
>pass. And I still would have had to spend a lot of time on hand
optimization.
>I think this would have taken at least 12 weeks of development time,
although
>since I didn't do it that way I'll never know.
Your argument, Eric, was that the microcode compiler generated code
that is equally as efficient as that you, or someone else, could have
constructed by hand. Megan in no way implies the use of assembly code.
The microcode compiler would generate an object file, which by your
own admission above, generated more code than could fit in the
memory space available. You accepted her argument that the human
was required to generate code more efficient than that produced by
the microcode compiler. You protest _too loudly_ my friend.
William R. Buckley
DIN41612 connectors are the type used in Multibus-II, VME and SUN, MAC-II's
NuBus, etc. They have a matrix of 3 rows of 32 holes in the socket, of
which you can buy connectors which only have the outer rows populated. This
means that there remain 64 holes, 62 of which would be occupied by a
wire-wrap (2-level) ISA-8-bit connector. This would allow placement of the
"daughter" board close to the S-100 board's surface and permit fitting it
into a single slot of the S-100, provided the end-plate were removed. They
can be had in either straight or right-angle versions, though the
right-angle normally sits on the circuit card while the straight versions
are mounted to the backplane. That's why I suggested that the gender would
have to be reversed.
Dick
-----Original Message-----
From: Dave Dameron <ddameron(a)earthlink.net>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Sunday, April 04, 1999 10:13 PM
Subject: Re: homemade computer for fun and experience...
>Hi all,
>At 10:52 PM 4/3/99 -0700, you wrote:
>>Well . . . I did think one could get two short cards on one S-100. I did
>>have something concrete in mind, too. If one inserts a wire-wrap 62 pin
>>(8-bit ISA) connector into a DIN 41612 right-angle socket
>>>
>What do DIN 41612 connectors look like?
>-Dave
>
>from a post in alt.forsale: original poster is: c-bristol(a)usa.net
(LA., CA)
*** OLD COMPUTER EQUIP. NOT IBM STYLE, UNIX PDP-11, VIC20********
DOCUMENTATION: SOFTWARE: UNIX: full sets of docs for v.6, v.7,
4.1BSD, 4.2BSD, 4.3BSD, SUN OS2, SUN OS3, SunView. About 3 big
file boxes of UNIX docs. Also have distribution tape of v.7
for PDP-11 licensed to me from SCO (Santa Cruz Operation) and the
PDP11 hardware it is licensed for. I paid $1350 to SCO for this
licence and tape, forsale now Cheap! Original v6 Lyons course,
1978?. Bell SysV Driver writing course, 1985.
DOCUMENTATION: SOFTWARE: DEC OS: Heathkit
H-11 paper tape operating system, papertape media and docs,
new, as shipped from Heathkit.
DOCUMENTATION: SOFTWARE: DEC OSs: Full set, RT-11 v2, v3, v4,
partial RSX-11. Also have the software on floppy and RK05, and
the PDP-11's that are licensed to run it. Also Heathkit
H-11 paper tape operating system, media and docs, new.
Also a couple of RSTS/E manuals. Disks also (RX01, RL01,RK05).
RT-11 set, XXDP Diagnostics, on 8" RX01 floppies and paper tape.MOSTLY
SOLD
DOCUMENTATION: SOFTWARE: DEC OSs: Full set, RT-11 v2, v3, v4,
partial RSX-11. Also have the software on floppy and RK05, and
the PDP-11's that are licensed to run it. Cheap! MOSTLY SOLD
DOCUMENTATION: HARDWARE: many DEC PDP-11 docs from
1970-1985 on microfiche. (Have reader too.) MOSTLY SOLD
So I've got a Q-bus system with 64KW (128KB) of RAM that is allegedly an 18
bit backplane. When I'm in ODT I can type:
@177770/
And enter values for 1777772, 1777774, 1777776, and then it wraps around to
000000.
If I start at 200000 it works until 3777777 and then wraps to 2000000. So
it seems to not cross a 64KB boundary. Also the boot area is 177300 ? so it
is in the upper 4K of the 64KB address space, is it legal to have memory
"above" the I/O page?
--Chuck
>> It is clearly the case that automated mechanisms are
>> inferior to a quality human intelligence. For anyone to think otherwise
>> is to relegate decisions of life to a computer program.
>
>We don't need to bring moralizing into the discussion. Most of us already
>relegate a lot of life's decisions, including some life-critical ones, to
>computers every day.
>
>Or are you the kind of person that refuses to buy cars with antilock brake
>systems?
Use of such systems does not imply that I fail to recognise their
limitations.
William R. Buckley
Heads up for you down under.
-------- Original Message --------
Subject: FREE Computers - Especially for collectors! (AUS)
Date: 5 Apr 99 02:48:51 -0900
From: "Lazy Bone" <zhulien(a)alphalink.com.au>
Organization: Badly Configured Clients, Inc.
Newsgroups: alphalink.forsale,comp.os.cpm
I have the following computers to give away if you collect them ASAP -
otherwise I will throw them away:
- Panther 128, 2 x 5.25" FDD, 6502 based, 128kb RAM?
- TRS80 MC10 (appears complete)
- TRS80 COCO
- TRS80 COCO2
- CAT
- Spectravideo SV318, Keyboard, Manual
- Spectravideo SV328, Keyboard, Manual, SV601 Expander, 5.25" FDD (SV902), Cassette
(SV903), CP/M 2.2...
- SONY Hitbit HB75B MSX
- Peach (Hitatchi MB6890) & software
- Atari 800XL
- Spectrum+ (needs keyboard replacement) & software
- Apple 2e, 5.25" FDD, various expansion cards
- Apple 2e clone, 5.25" FDD
- BBC ModelB, Builtin modem & ROM, Colour Monitor, 2 x 5.25" FDD
- Sinclair QL (Telecom ComputerPhone), 2 x microdrives
- Microbee model 2, seikosha printer
- Microbee model 2
- VZ300
- VZ300 (faulty?)
- Sega Master System
- Sega Master System 2
- Sega Megadrive 2
- Nintendo NES
- Sinclair ZX81 in original box missing cables
Since I picked up 40 or so computers from a friend today who is going
abroad, I cannot keep the above because of lack of space. If you want
to collect anything, please ring me ASAP on 03 98131630.
Julian
Well. Over forty messages spawned from this topic. I am very
most certainly grateful to each of you who has taken your time and
expertise to add knowledge to the subject.
I am not going to pursue the 11/73 any longer, because it is
hardly a DEC machine, anyway (physically at any rate) and because I
think that I would be better served by putting the resources into my
11/44. I have two 11/23s which *are* true-DEC, and perhaps these
can be made to hold aloft the LSI banner in my collection.
I definately want the 11/73 for the data on it's HD, tho.
This leaves the 11/43a system and the uVAX II to be made to speak
RL02, and then there's some form of networking between them, and also
to a contemplated 486 or 586 platform dedicated to one of the PDP11
emulators. To this machine I can then install my SCSI 9trk drive, and
do real handy things like CDROM and Media Conversion.
I know the PR1ME 2550 has an ethernet port on it, and a SCSI port,
and it has a Kennedy 9100 native to it...
Sigh. I have an appointment with a friend of mine who is an
electrician, to get an estimate on re-working my pitiful sixties-era
house wiring. If I squeeze every drop out of the taxes this year, it
might just pay for the sub-panel and the conduit run to the Machines.
Yup. I got it *bad*...
Thanks again everyone. I am going to take stock of my DEC module
situation and then put some things up for trade... I'm angling for
an RL02 on the uVAX... hint hint hint.
Ah, damn.. forgot about the MINCs....
Cheerz
John
> Why restrict yourself to PC-clone keyboards? May as well just put a
> serial console port on and ...
>Because, as I have traced around countless motherboards of all
>kinds and found this is far easier to cobble up one using keyboard,
>KB controller stolen from old motherboard, than trying to design
>and build a parallel KB or design an i/o and needed codes for
>terminal.
"Designing an I/O and needed codes for a terminal" is dead simple.
Put in a UART, put in TTL to RS232 or 20mA level translators, and you're
done. Want to output a letter in the console? OUT 00H. Want
to input a character? INP 00H.
Come on guys, I'm *not* trying to be difficult. I'm pointing out
that a serial console interface is:
1. Universal. No need to find a particular keyboard design or a
particular monitor scan rate and/or interface.
2. Easy to build - it's just a UART hooked to an I/O port.
3. Easy to program - heck, with many UART's you get interrupt-driven
input and output for free. And no need to write a terminal emulator!
4. Doesn't take up valuable memory space like memory-mapped video.
5. Gives enormous interfacing flexibility. You can hook it to a terminal,
you can hook it to a ASR-33, you can hook it to your PC-clone,
you can put a modem on it and dial into it. You're in fat city.
In brief, it's the option that gives you the most advantages with the
least effort. A no-brainer!
> I have heard horror stories from some who did the parallel
> kbs and they're no longer made. I could be mistaken.
And I think folks who build video generators will run across the same
problem in the future. The computer will easily outlast several generations
of monitors and keyboards, and you want to be able to still use it
in 20 years, don't you? I can use my 24-year-old S-100 boxes with
serial console interfaces just fine today, just as I can use my 30-year
old PDP-8 with anything that has a serial interface, and I expect that
I'll be able to use them 30 years from now. Do you think you'll be able
to buy new VGA (much less EGA) monitors 20 years from now? Heck, the
FCC has an executive order that NTSC television will be gone and
replaced by HDTV in less than a decade - better start buying up
composite-input monitors now while they're still out there!
--
Tim Shoppa Email: shoppa(a)trailing-edge.com
Trailing Edge Technology WWW: http://www.trailing-edge.com/
7328 Bradley Blvd Voice: 301-767-5917
Bethesda, MD, USA 20817 Fax: 301-767-5927
>> computers, the service representative came to the site, opened a panel
>> on the operator console, and changed the 5 1/4" floppy disk. By doing
>
>I think I read somewhere that the 8" floppy was originally designed for
>this purpose.
This may be. Yet, this was my introduction to the 5 1/4" format. At the
time,
I worked for Remex, a division of EX-CEL-O corporation, and they made
8" and 5 1/4" inch drives. The year, IIRC, was 1977.
William R. Buckley
>>The field guide claims at its top:
>>
>>*This list may always be found on sunsite.unc.edu, in the following
>>*directory:
>>*/pub/academic/computer-science/history/pdp-11/hardware/field-guide.txt
>But for how long will sunsite.unc.edu resolve to metalab.unc.edu?
Probably forever :-). Still, I should fix it up with the new
"sanitized" name.
It was only a few weeks ago that I thoroughly replaced my "triumf.ca"
address on the web pages there...
--
Tim Shoppa Email: shoppa(a)trailing-edge.com
Trailing Edge Technology WWW: http://www.trailing-edge.com/
7328 Bradley Blvd Voice: 301-767-5917
Bethesda, MD, USA 20817 Fax: 301-767-5927
