< Not everyone has a Quest Elf. I, too, want to go beyond it, but for
< aesthetic reasons, I want to stay close to the original. My vision is
< a compromise between what we had in 1977 and what we would have wanted
< if we could have gotten it for the same price. When I built my Elf, I
< followed a friend's advice and installed a wire-wrap socket for the CPU
< He rolled his own I/O ports, with relay drivers and built a robot. I
< never did add anthing to mine, and quickly ran out of things to do with
Doing all that with a bas elf wasn't hard but very awkward.
It didn't latch the high address so 256bytes were it.
IO was what it was(switches and the Q led)
There was no easy expansion without corrupting the base design
so that some of the simplest programs did not run.
< I always wanted an Elf II, but couldn't afford the board. I wish now I
Same here but at teh time I was into S100 and just wanted to play with the
1802 a tiny bit and that was cheap.
< had saved for it. I got a 32k PET instead. Ah, well; choices. In any
< case, I liked the slots idea on the Elf II, but I don't recall too much
< materializing for it. The Elf II at the Computer Museum of America in
< San Diego has a plexiglass box over the boards and all the slots full.
< One was memory. I don't know about the other two. For that matter, the
Memory, Parrlel ports, serial ports, 1861 video board(may have been a
base level board option). The most highly developed elf was the one from
Netronics (ELF-II)
The VIP had a ram card, rom card, IO card and a sound effects card. Never
saw any of them. They were real easy to make.
My idea of a 1802 system was more like the 1802 Eval board rom RCA that
was unlike the elf series.
My 1802 wish list for the record.
Up to 32kram, 32k rom using standard pinouts so the 32k rom
can be EEpro, Eprom or flash. The 28 pin site can also accept
24 pin devices (6116, 2716, 2732...).
Minimum of one parallel out and one parallel in.
Elf style front pannel for programs with 6 hex leds (address and
data). data input would be toggle switches as they while not
cheap are easy to get and mount.
serial port, bit bashing serial IO gets tiresome and is limited
in speed.
VIP style cassette IO (tape storage)
proto area with holes enough to build a few IO things.
Bus brought to one connector (VIP compatable)
The reason for that is there are Tbasic, Pilot and other languages and
tools that all want more than 256 byts and Q-led.
If some one were to do it a "advanced 1861" in FPGA. the 1861
was a primitive device that did video DMA, With a little design effort
a similar device and be put in FPGA that would provide 256 horizontal
by 128 vertical using 4k of ram as a bit map. This enough to better
graphics and even display 32x16 characters using a 8x8 cell.
Going much further with 1802 is self limiting as it was slow and actually
a crude CPU. It was also like the PDP-8 in that it was blessedly simple.
Allison
Joe,
I wish I were there.
You should hang the DG core plane on the wall. They are great art.
I think all core you get should be kept. Usually there is so much good (old)
gold in them they go to scrap first. While later core planes, including the
DG, didn't use much some of the early examples are spectacular. And, who
knows, someone might want to get an old Nova 800 running again.
The small pizza boxes are Sun compatible X-Window Terminals. Plug in a
multisync SVGA monitor (preferably one good to 1280X1024), PS/2 mouse and
keyboard and you should be able to get it to come up and run digs somewhere in
the windowing system. I say Sun compatible because of the keyboard port. It
would be interesting to know if Sun chips or the 68020/68881 chips were in it.
Usually generic X-Window terminals used Motorola chips. If it had Sun chips it
would be a Sparkstation of some kind. Probably not a Spark though, no SCSI
port.
HDS (Human Designed Systems) made terminals to be hooked up to mainframes.
Almost all terminal makers brought out a X-Window terminals for Ethernet
networks. HDS was well respected, I'm not surprised that some of their
machines got out there. Most X-Window machines had this many ports, Sun
keyboard excluded. They were platform independent, relying on TCP/IP and X-
Windows which usually booted from ROM. This one looks like it would hook up to
any kind of Ethernet you had, keyboard, mouse, parallel printer, modem, serial
tablet, are there any leftover ports, oh yes the Sun Keyboard (or the PC
keyboard if you hooked up a Sun one). My guess is that this is a later
Motorola based X-Window terminal that is nearly plug and play on a Sun Solaris
Ethernet system.
NOTE: X-Window terminals were often crammed full of memory (2 to 16meg
generally), usually SIMS. This often gets stripped first, even before the
surplus shop gets it. Look for signs the case has been opened. If you can,
check the machine yourself. Spark clones have 32 to 64 Megs of Ram, have good
trading value.
the earliest of these are about 10 yrs old so they can be on topic. Let us
know what else you find!
Paxton
PS I see more current info out there after reading the mail. If it is an
intel/TI system those are fairly rare and, I think, worth collecting.
On Nov 25, 23:44, Allison J Parent wrote:
> Front pannels don't work with Z80s if... DRAM depends on the z80 for
> refresh. Reason is the stopped state is a very long wait state.
Do you mean if you execute a HALT instruction? If you do that, the Z80
behaves as if it's continuously executing HALT instructions, performing
repeated bus cycles, including the RFSH signal part.
--
Pete Peter Turnbull
Dept. of Computer Science
University of York
On Nov 26, 0:31, Ethan Dicks wrote:
> I don't think you answered the same question I did. The "essential"
thing
> and the thing that there was only one vote in favor of was having the
2101
> sockets IN ADDITION TO the 62256 socket. So far, only one person, Hans,
> has asserted that the 2101 sockets are a good thing.
Add my name to Hans'. I don't mind if I can only have one or the other at
any given time, but I happen to have a few 2101s and it would be nice to
use them.
> Not everyone has a Quest Elf. I, too, want to go beyond it, but for
> aesthetic reasons, I want to stay close to the original.
That sounds just like my ideal :-)
--
Pete Peter Turnbull
Dept. of Computer Science
University of York
I have managed to find and cobble together enough bits of hardware to have
an operational vaxstation .... I think.
I've never played with one before or even seen one. What now?
The box is a model VS42A and has a 3.5" floppy and 2 X 100Mb internal SCSI
hard drives. It has what looks like 8Mb of RAM to me, whatever is on the
main board plus a 4Mb extension.
On powering up it says KA 42-A v1.3, does a hex countdown and finishes with
a ">>>" prompt.
Command "b" causes it to display ESA0 and stop.
Command "?" gives an error message.
Command "c" causes a drive to start. It then displays an error message "ISP
ERR PC=00000000" and then lists a table I can't decipher that seems to
list drives and includes "VMS/VMB" and "Ultrix" along the top. It then has a
prompt " [ESA0:] >>> ".
At that point command "b" results in a series of errors:
83 BOOT SYS
?41 DEVASSIGN,B
84 FAIL
How can I find out if it has an operating system? or have I already proved
it hasn't?
None of the stuff I have found on the web so far goes this basic.
It looks like it is at least NEARLY 10 years old.
Thanks
Hans Olminkhof
The basic elf was an 8bit address only design. The high order bites were
not latched.
It's memory was 256bytes (2101s) and an optional 32byte fuse prom. When
the prom was enabled it overlayed the first 32 bytes. The upper address
bytes were meaningless as no logic saw them. Very limiting design.
< > > o Circuit to ghost EPROM at $0000 until first address access at
$80
< >
< > I still would go for a better decoding - just the high bit is to short
< > Maybe there are some spare gates to use ?
<
< Wait a minute. We have been having an extensive offline conversation
< and you said that 32K of RAM and 32K of ROM is enough. It can be more o
< of either, at a cost of gates and complexity.
The VIP had 512bytes at 8000 and up to 4k at 0-0fffh/
< > Esential to be as close as possible to the original design.
<
< One vote for, several against or abstaining.
if you stay close to the quest design you cannot have much (and none of
the options) all of the options are desirable as most people added them
somehow or another.
< I'm not inclined to do dual 1852's. We you and I have discussed, the 18
< uses three ports, the switch/display is another port, leaving three lef
< over. While ports are scarce, they are no so scarce as to overshadow th
< benefits of a bit-programmable I/O port.
Use port one to select banks of ports (RCA app note). Then ports are
cheap and it only takes another latch.
ARE 1852 available and what do they offer over a simple cheap port.
< > Data transfer via Q is way more fun (Hi Alison :).
< > And since we don't need high speed transfer (2400 is ridicoulous i
< > we can do 110 :) a complete software solution is a great thing to do.
<
< I have no problems in principle with a software UART, but I do have
< something to say about the speed. 2400 baud is *not* a ridiculous
< speed, especially if you want to talk to an external device that has
< a fixed clock, say, a serial-to-LCD board. The other issue with a
< software UART is timing. If you use a hardware UART, it needs a
< crystal of a particular frequency, but the CPU does not. You can then
< "clock chip" the 1802 up (to use a Mac term) and not recode your serial
< routines.
Use the q led and EF1 for casette port. Uart for TTY/term.
< I still have yet to hear why the 1855 Multiply/Divide Unit is worth
< the real estate. Sure, it's a neat chip, but unless it has a purpose,
< I can't see including it.
Never mind finding it.
< but if I maximize the appeal of the standard I/O ports, I'm likely to se
< a few dozen. If I can't sell 60, I can't afford to invest in 100 PCBs.
And if its only the quest design I have one already. It's appeal wears
off real fast and it's was not designed with expansion in mind.
Allison
< Not trying to be a snob here, but true "Front Panel Theory" can only be
< practiced on a computer where the 'innards' are exposed. Most
< microprocessors are too integrated to support a "real" front panel. This
< one of the reason they died out fairly quickly in the micro world but li
< for quite a while in the mini-world.
Wrong, wrong wrong. They died because of a multitude of things one being
ROM monitor is cheaper to implement than 16-22 switches and more flexible.
That and after you've baned the loader in 5 times and basic still isn't
up and your finder hurt... Plus it made the machine intimidating and
complex looking compared to say a KIM-1
The 8080 altair had one and it was quite useful but there were more
switches and TTL on the board than the CPU, RAM and IO combined!
Allison
< This might be a bit of an odd question, but can anyone point me in the
< right direction to find info on theory of operation of a front panel?
< have a z80 based computer which I built a few years ago (wire-wrapped)
< which uses an eprom for program storage. I would like to add a front
< panel (switches and lights) to it to get better aquainted with the old w
Find a copy of bursky's book The S100 Bus Handbook.
Front pannels don't work with Z80s if... DRAM depends on the z80 for
refresh. Reason is the stopped state is a very long wait state.
theory wise it's farly simple but there are a lot of repeated circuits
as you have to buffer everything and do some work centered around the CPU
timing.
Allison
It's replies like the one below that make my education seem woeful to me.
A
-----Original Message-----
From: Allison J Parent <allisonp(a)world.std.com>
To: Discussion re-collecting of classic computers
<classiccmp(a)u.washington.edu>
Date: Thursday, November 26, 1998 3:54 PM
Subject: Re: Audio Cassette formats; what about ADAM?
>< What about the ADAM computer from Coleco??? It uses a digital tape that
>< holds (around) 256K or so... (Never set mine up yet).
><
>< Is there any way you could run that thang thru an audio player and have
>< PC routine re-digitalize it, or are you stuck with read a thing and
>< serial-send it over to another PC?
>
>No! It's digital saturation like a floppy and the encoding is to the
>flux reversal timing.
>
>Adam is digital stauration recording like a floppy only slower, audio
>tape is audio frequency/phase change and the medium is the linear portion
>of the BH curve. They are very different from each other.
>
>Allison
>
>
