FYI:
good Docu on tonight-
PBS:
Dayton Codebreakers
National Cash Register Co. conducts secret experiments to break the
Enigma Code; engineer Joseph R. Desch helps end World War II.
=Dan
--
[ Never put off till tomorrow, What you can do the day after tomorrow ]
[ Pittsburgh ---- http://www2.applegate.org/~ragooman/ ]
Anyone know what this is? Looks like a weird data entry system to key
in data and store it on tape for processing who knows how. Although
the description could just be off...
ebay item # 250164567149
--
"The Direct3D Graphics Pipeline" -- DirectX 9 draft available for download
<http://www.xmission.com/~legalize/book/download/index.html>
Legalize Adulthood! <http://blogs.xmission.com/legalize/>
--------------Original Message:
Date: Wed, 12 Sep 2007 13:31:18 -0500
From: "Ethan Dicks" <ethan.dicks at gmail.com>
Subject: Re: 8-bitters and multi-whatever
On 9/12/07, M H Stein <dm561 at torfree.net> wrote:
>
> From: "Ethan Dicks" <ethan.dicks at gmail.com>
> >Since I couldn't afford an IEEE-488 disk drive, rather than just move
> >files back and forth on tape, basing it upon the cable and software
> >from a contemporary "Byte" magazine, I fabricated my own
> >nybble-with-handshake cable between the user ports of the PET and the
> >C-64, and moved stuff from one to the other over that.
>
> You mean you didn't just make a simple cassette "null modem" cable?
> I still have the 30 footer that connected my upstairs "play" PET to the
> downstairs "work" one. Lots of people (especially schools) "networked"
> them that way in those distant days.
Until you mentioned it now, I never would have thought of it. Back in
the day, I never saw any articles in the journals about that, and
nobody at any of the user-group meetings ever mentioned it or showed
it off, but thinking about it now... I can see how it could work.
Just a passive cable? Do you have any special notes, or was it just
SAVE "FOO", 1 and LOAD "FOO", 1?
-ethan
===================================================
-----------Reply:
Simple as that. Out to In, In to Out, and ground; preferably shielded,
compatible with pretty well all models.
Type LOAD "FOO" on receiving unit, run up/downstairs and type SAVE
"FOO" on the other, using the alternate port on the unit that had a "real"
cassette drive (2001 & VIC20 in my case, with an 8032/8050 and a
massive Centronics 101 printing boat anchor at the other end), then back
down/upstairs to play/work. Remember that an 8050 2FDD was around
$2000+ back then IIRC, so one was enough for me.
In the classrooms they'd have a "hub" (but I don't recall now whether they
were passive or needed amplification). The teacher would tell everyone to
type LOAD "FOO" and when they were ready everyone pressed return and
the teacher would enter the SAVE. If anyone wanted to save their master-
pieces, then one at a time they could send them back to the "server" and
copy to disk.
Since Jack T had his beginnings here in Toronto, Commodore had a pretty
strong presence and when the province decided to put computers into the
classrooms most of them were PETs; 2001s, then 4032s and finally C64s,
although by that time Apples (and clones) were also becoming pretty
commonplace. That's also one of the reasons TPUG (the Toronto PET
Users Group) was so successful and in fact is still active today, not
to mention Jim Butterfield's (another Torontonian) considerable support
and contributions.
mike
The good news is that the symbols (at least for modernish interfaces)
seem to be being standardized. Be nice if they back-standardized though
for things like serial and parallel.
Another issue with words is "which $LANGUAGE" - I remember distinctly
opening up the Volvo service manual and being totally confused by
"bonnet" when I was about 12. I imagine that someone in England would
be even more confused by "hood" (since I think it means the drop-top on
a convertible over there). Symbols are fair in that they are equally
inconvienient for all.
BTW "la computadora" is the standard in Latin America (where the stop
signs are a red octagon with "ALTO" in them).
What I would like to see is connectors designed to be easy to mate. I
dislike struggling with a connector because I'm some small fraction of
an inch off and eventually having to take everything off the machine
and turn it around so I can see what I'm doing. The modular jacks are
good for blind connections, but USB is terrible (and most D-subs are
hard, too. At least 13W3 gives you a tactile method to determine
whether you're right-side up).
------------Original Message:
Date: Wed, 12 Sep 2007 19:56:02 -0400
From: "Roy J. Tellason" <rtellason at verizon.net>
Subject: Re: 8-bitters and multi-whatever
On Wednesday 12 September 2007 19:45, Ensor wrote:
> Hi,
>
> > You don't even need "rs232 levels".
>
> MIDI is a "current loop" interface isn't it?
Yup!
But my point is that in prototyping some small SBC the rs232 stuff is about
the only thing on there typically that needs other than logic power (+5V)
unless there's some analog stuff there on the board that needs it.
MIDI, in every implementation I've ever seen, uses only a 5V supply.
I never did understand why current loops weren't used more...
========================
-----------Reply:
On short runs you can usually get away with TTL levels on RS-232 as long
as you limit the input voltage swing with a resistor and a couple of diodes
or use an optocoupler.
m
>
>Subject: Re: 8-bitters and multi-whatever
> From: "Ethan Dicks" <ethan.dicks at gmail.com>
> Date: Wed, 12 Sep 2007 02:02:57 -0500
> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
>
>On 9/11/07, Allison <ajp166 at bellatlantic.net> wrote:
>> There were a few simple schemes but excluding myself how many hobbiests
>> back then had two or more systems?
>
>In 1982, the year you quoted for those Arcnet networks, at age 16, I
>had 4 systems, a PET, a C-64, a Cosmac Elf, and a PDP-8/L (that I was
>trying to repair - took until 1984, when I finally tracked down a
>printset), but I'll grant you that at the time, the number of folks
>that had multiple systems were probably dwarfed by the number of folks
>who had only one. Of those, due to minimal I/O and/or functionality,
>only the PET and the C-64 were "real" systems.
I knew I couldn't be the only one but I figured not many. I was rare in
I had at least 4 systems that would run CP/M making the need for interchange
more deireable. By that same year I also had COSMAC ELF, SC/MP 8a-500,
National Nibble basic, IMSAI IMP-48, Motorola 6800D1, NEC TK80, and a
LSI-11 with TU58.
I was in contact with enough people that the incidence of multiple machines
was low. the more common case was a apple, TRS-80 or S100 crate with storage
and one or more SBC that might have enough memory for TinyBasic. The exceptions
were usually business or schools.
>Since I couldn't afford an IEEE-488 disk drive, rather than just move
>files back and forth on tape, basing it upon the cable and software
>from a contemporary "Byte" magazine, I fabricated my own
>nybble-with-handshake cable between the user ports of the PET and the
>C-64, and moved stuff from one to the other over that. I might have
>used serial, if I'd had an ACIA-based port for my PET (there were a
>couple that sat in an expansion ROM socket), or if I'd understood more
>about the nature of serial comms and crufted up my own bit-banging
>routines for the PET (the C-64 had that in ROM already). I understood
>parallel communications, so a nybble at a time it was.
Mine started when I needed to get stuff from the various CP/M systems
that even when they had disks were incompatable hard sector to soft
or 8 and 5.25. I started with serial peer to peer as in pipmodem and
similar. Later I did a two system resource sharing that grew to allow
up to a potential 256 systems. In '82 the whole thing peaked with a
multiprocessor S100 crate with intercommunications via pooled memory.
>
>Later, around 1983, when I picked up a VIC-20 on clearance for around
>$70, I would certainly would have liked to have had a Commodore
>network (based around the user port, most likely), but was unaware of
>anything I could build for myself, and certainly couldn't afford any
>of the "disk sharing" hardware I'd seen advertised to share PET disks
>amongst multiple machines.
Likely If i'd had more contact with the non-CP/M s100 world and the
DEC PDP-11 world I'd have evolved things differntly. It didn't hurt
that I'd had prior experience with the BOCES LYRICs PDP-8 and PDP-10
timeshare systems. The S100 world allowed me to venture into a more
hardware intensive world.
>It took me a few more years to learn enough about serial comms and
>computer networking to be able to roll my own hardware and/or
>software, but working for a serial comms networking company had a lot
>to do with that. I would have loved to have been able to buy or build
>something inexpensive, no matter how slow, but even a multi-serial
>solution would have strained my high-school budget, as I presume it
>would have strained most hobbyists' budgets, or perhaps home
>networking would have gotten rolling before the days of Arcnet.
>I think the first network I had any hands-on experience with was
>AppleTalk/LocalTalk, when I helped my mother with a Corvus disk drive
>and a room full of 512K Macs, just before she started her own business
>(fortunately, by the time she did, she could afford a 20MB drive per
>CPU, so the network was for printing only).
By time the Mac hit I'd seeen DECnet and mixed PDP-11 and VAX system
in large networks with remote printing and all the trimmings we see on
the internet.
>AppleTalk was a great step forward for home networking. It's a shame
>that other vendors didn't follow in Apple's footsteps for many years.
>I think I had an Amiga for four or five years before I attempted to
>even do any serial networking (using DNet). It was well after 1990
>before I was able to stick an Amiga on an Ethernet network, and that
>was with a $300 card! (there was a Zorro Arcnet card - the A2060, but
>I knew I wasn't going to bother with Arcnet by that time).
Appletalk was a really good, it's biggest feature is low cost both
in hardware and memory footprint there were peripherals that would
talk on the same net.
All of the things I did and got to see and use colored my perception
of what computers could do. Usually it was far greater than marketed
capability. I'd believed in '83 that if a VAX or PDP-11 could network
around the world a room should be easy enough. Also I'd seen what large
machines could do years before and figured the only differnce doing it
with a micro was either scale or speed. In the span from'82 to '89
with PCs getting faster and Ethernet and internet both catching on
there was a communications explosion. What isn't discussed here
is what the radio amateurs were doing with Packet networks and X.25
protocals. In some cases they were prototyping portable (toteable)
networks.
Allison
Does anyone have the schematic for an 874-D power controller?
Or better yet, a good used circuit breaker?
At least one of the three (ganged) breakers is internally flaky
and will turn off if the handle is pushed upward all the way to
"ON" (they work if the handle row is carefully lifted just far
enough but obviously that is not reliable).
It looks like the (original-type) Heinemann breakers are available
>from Newark, and similar ones from Mouser that will probably fit,
but they are *very* expensive new...
thanks
Charles
>
>Subject: Re: 8-bitters and multi-whatever
> From: "Chuck Guzis" <cclist at sydex.com>
> Date: Thu, 13 Sep 2007 10:15:21 -0700
> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
>
>On 13 Sep 2007 at 13:43, Jules Richardson wrote:
>
>> I suppose I've always seen it as "electronically connected computers" or
>> somesuch - i.e. it doesn't imply anything about what data is shared (or how),
>> just that something *can* be transferred without sneakernetting information
>> around.
>
>So my use of the acoustic-coupled modem out of a TI Silent 700 on my
>MITS Altair 8800 to a CDC 6600 over phone lines was networking in
>1976? I did my source prep and assembly on the mainframe and just
>downloaded my programs to run them. Of course, I had to key in the
>basic terminal/download code via the front panel switches, but that
>wasn't a big deal.
>
>As far as coupling two computers together--well, that's VERY old.
>Goes back to the 1950's at least and probably is older than that.
At that time it was a loose term. Alohanet was one of the first that
really solidified the term and application. Generally there was/are
two basic classes host and client or Peer to Peer. The Altair<>CDC
was more like the first than second.
When I was doing it I had been attempting to have facilities not unlike
VMS/DECnet. The goal was from any one machine I could connect, manage
and use files from another machine and the files could exist on any
enabled machine (that had the requested resource). The goal I achieved
was a diskless machine could boot from one, use files from another and
the actual terminal was connected to a third, plus print to a fourth
machine that had the printer (and could buffer the transfer). The basic
scheme was actually simple but getting CSMA/CD between my ears the hard
part. It was node to node (addressed) conectivity with systems added
to the net able to broadcast it's presence. The only thing was it was
all and only CP/M.
Allison
all caps because it's an acronym...
Jule's Own Version of the International Algorythmic Language developed at SDC in Santa Monica more than a few moons ago
s shumaker
-------------- Original message from "Chuck Guzis" <cclist at sydex.com>: --------------
> I spotted this in my morning news perusal:
>
> "Digitization? The entire network runs on software known as Jovial,
> so old there are only six programmers in the country who know how to
> write it. And incredible as it seems, family minivans with NavStar
> have more sophisticated location guidance than some aircraft."
>
> from: http://www.msnbc.msn.com/id/20724859/
>
> Well, make that seven. I remember JOVIAL (it's all caps BTW).
> Worked on an NWL (or maybe it was NSRDC) project in it. Anyone else?
>
> Cheers,
> Chuck
>
>
From: "Ethan Dicks" <ethan.dicks at gmail.com>
Subject: Re: 8-bitters and multi-whatever
On 9/11/07, Allison <ajp166 at bellatlantic.net> wrote:
> There were a few simple schemes but excluding myself how many hobbiests
> back then had two or more systems?
>In 1982, the year you quoted for those Arcnet networks, at age 16, I
>had 4 systems, a PET, a C-64, a Cosmac Elf, and a PDP-8/L
<snip>
>Of those, due to minimal I/O and/or functionality,
>only the PET and the C-64 were "real" systems.
>Since I couldn't afford an IEEE-488 disk drive, rather than just move
>files back and forth on tape, basing it upon the cable and software
>from a contemporary "Byte" magazine, I fabricated my own
>nybble-with-handshake cable between the user ports of the PET and the
>C-64, and moved stuff from one to the other over that. I might have
>used serial, if I'd had an ACIA-based port for my PET (there were a
>couple that sat in an expansion ROM socket), or if I'd understood more
>about the nature of serial comms and crufted up my own bit-banging
>routines for the PET (the C-64 had that in ROM already). I understood
>parallel communications, so a nybble at a time it was.
--------
You mean you didn't just make a simple cassette "null modem" cable?
I still have the 30 footer that connected my upstairs "play" PET to the
downstairs "work" one. Lots of people (especially schools) "networked"
them that way in those distant days.
mike
