A few weeks ago, some people in here were talking about putting network
cards in IBM PCs or XTs or something...
As it happens, I ran across a box of 3com 3c503 network cards (AUI and
10BaseT ports, 8 bit ISA card).
If anyone wants one, lemme know, I'm asking $5+shipping, and I'll have
the box with me at Dayton if you want to harass me about them, then.
Pat
--
Purdue University ITAP/RCAC --- http://www.rcac.purdue.edu/
The Computer Refuge --- http://computer-refuge.org
Hi,
I'm looking for Software & Manuals for any of the MUMPS implementations for the PDP-11,
e.g. MUMPS-11, DSM-11 or M/11+.
Can anybody help?
Regards,
Ulli
________________________________
Hi, all,
I was staring at an SBC I have here with a 6MHz Z-80, some ROM, some RAM,
and a 26-pin off-board bus for some Z80-PIO boards (this thing was built
as a multi-parallel-printer switcher). I've been musing about what it
would take to boot CP/M up on this.
For user I/O, I was planning on a console serial port and a
terminal/terminal
emulator. I have IM6402s on hand, but I'd be interested in hearing if
certain other chips are preferred, based on what BIOS code is floating
around out there. I also have a 16550, but I don't think I have any
Z80-SIO chips handy.
For mass storage, I was planning on either Compact Flash or an SD card.
I think I've seen both as I googled around for modern SBCs. Any of the
media I have lying around is plenty large enough (I even have some 4MB
CFs and a 2.5MB full-sized PCMCIA flash card on hand).
I am a little unclear, though, about how traditional CP/M systems
were set up for ROM and RAM. Was it common to use a "shadow ROM"
in low mem at reset, then have the BIOS live at the top of memory?
How did 64K RAM CP/M machines handle the BIOS? Did they temporarily
ghost the ROM on top of RAM until some bit of code could read ROM
and write RAM then bank out the ROM? Since I think I "need" at
least 48K of RAM, I was planning on a pair of 62256s. I could easily
do 56K of RAM low and 8K of ROM high, I think, unless there's some
other arrangement that's obvious to try for a simple design.
I've never tried writing a BIOS for a CP/M machine, but my understanding
is that things are modular enough that once you know what I/O chips
you have and at what I/O addresses, for a straightforward, non-clever
design, the coding is equally straightforward and non-clever (but please
feel free to enlighten me if otherwise).
Thanks for any tips, especially from anyone on the list who has ever
rolled their own CP/M machine.
-ethan
--
Ethan Dicks, A-333-S Current South Pole Weather at 4-May-2008 at 19:40
Z
South Pole Station
PSC 468 Box 400 Temp -74.2 F (-59.0 C) Windchill -105.4 F (-76.4
C)
APO AP 96598 Wind 7.4 kts Grid 77 Barometer 691.6 mb (10194
ft)
Ethan.Dicks at usap.gov <http://www.classiccmp.org/mailman/listinfo/cctalk>
http://penguincentral.com/penguincentral.html
-----REPLY-----
Hi Ethan,
Funny you should mention the subject, I am working on a very similar
project.
Last year, I made a completely home brew Z80 computer with prototype boards.
It is a fun project and you can definitely build your own CP/M computer from
scratch. It really is not that hard.
This year, I am remaking the design using manufactured PCBs.
I recently got my first batch of prototype PCBs and have been building up
and testing them.
So far, I have gotten the CPU, ROM, RAM, UART, and most of the glue logic
working and tested.
It is not complete yet as I still need to wring out much of the hardware and
have not even started on the PPI or RTC.
However, last year I was able to boot the previous system into its monitor
and even boot CP/M.
CP/M used a 32K ROM drive for drive A:, a 448K RAM drive for drive B:. I
implemented an IDE port and a hard disk for drive C:.
Those all worked pretty good. I built but never tested a floppy drive
interface.
The whole system is pretty simple, uses plain 74LSxxx chips, no programmable
parts (except the EPROM) or hard to get parts.
No SMT or funky technologies, just plain through hole DIP chips.
I have all the software and am presently going through the library
reinstalling it on the new system.
So far, I have most of the easy stuff working. I do have the RAMless
monitor working and next will be the regular monitor.
Finally it will be the CP/M system and the RTC software.
Anyway, if your interested, I am keeping a small Google group of files and
photos at:
http://groups.google.com/group/n8vem
Thanks!
Andrew Lynch
As a tangent to the "first" computer on the internet, I reference this
interesting link, showing the IMP log, along with the date and time of
the "birth" of said [I][i]nternet.
See:
http://www.lk.cs.ucla.edu/first_words.html
-eric
At 20:05 -0500 8/17/08, Dave wrote:
> I have to agree there. And $500 for a 7300 is a tad on the high
>side. I had three of them (two 3B1s and a 7300) and reluctantly
>parted with one. I became much less reluctant when the guy offered
>me $300. The first machine is one I will keep even if the prices go
>sky high, as it was given to me years ago by a classiccmp member (hi
>Mark!), although for the life of me I have no clue where the mouse went.
>
> Does anyone have disk images of the 7300/3B1 OS distribution?
Hi Dave, but IIRC, I just put you in contact with Robert, who gave
you one of his. Though he got some of his from me, so it may have
been indirectly one of my machines...
If it were mine, and I'd given it to you, I'd have no objection to
your selling it for as much as you can possibly get for it. My theory
is, the more value it acquires (by somebody paying for it) the less
likely it will be to get scrapped, hence the more likely it'll be to
be preserved. On the other hand, I *know* you are a knowledgeable
collector and know which end of the soldering iron gets hot without
having to grab it, so I'm happy it's in your hands.
One reason for me to take this philosophy is that I don't have time
to do myself the things I'd really like to do with my collection -
like imaging floppies! I have 'em, but not imaged. They are in
climate-controlled storage - that's the best I can say for myself.
I'll hunt for mice. I don't think I kept a spare, but if I did, I'll
let you know.
--
- Mark 210-379-4635
-----------------------------------------------------------------------
Large Asteroids headed toward planets
inhabited by beings that don't have
technology adequate to stop them:
Think of it as Evolution in Fast-Forward.
Does anyone on the list know anything about this? I was given a Mindset
with two plug-in modules:
Mindset Host Adapter Interface Module
Mindset Hard Disk Cartridge
The former has a bus connector at one end and a DB37F on the other. No
disk controller chip, just a bunch of TTL logic. I'm guessing either a
proprietary bus or SCSI managed in software (a la Apple 2 Sider).
The "Hard Disk Cartridge" contains a pair of EPROMs.
Any information appreciated!
Steve
--
http://www.kempa.com/wp/2004/03/09/vinyl-data/
Excerpt:
One strategy that major record companies have been employing lately to
deter downloading is adding bonus computer content to new CD releases. I
recently discovered that this technique is not unique to CD?s, but had in
fact been practiced in the vinyl era as well. That?s right: there were a
handful of records released in the late 70?s and early 80?s that contained
computer programs as part of the audio. This is totally insane, and totally
great.
Most of these programs were written for the Sinclair Spectrum home
computer series. The Sinclair Spectrum was a relatively cheap home computer
system that used a television set as a monitor and loaded programs from
tapes. It thrived in England in the early 80?s:
-----
240. [Literature] "It was the best of times, it was the worst of times,..." --
opening line of Charles Dickens, _A Tale of Two Cities_
--... ...-- -.. . -. ----. --.- --.- -...
tpeters at nospam.mixcom.com (remove "nospam") N9QQB (amateur radio)
"HEY YOU" (loud shouting) WEB: http://www.mixweb.com/tpeters
43? 7' 17.2" N by 88? 6' 28.9" W, Elevation 815', Grid Square EN53wc
WAN/LAN/Telcom Analyst, Tech Writer, MCP, CCNA, Registered Linux User 385531