Does anyone have information on undocumented 8080 instructions? There's
plenty of information out there about undocumented Z-80 and 8085
instructions, but I haven't found anything on the 8080.
Some of the non-Intel 8080 and 8080-compatible parts were independent
designs, rather than licensed second-sources using Intel-provided masks,
so those might have different behavior for the undocumented opcodes.
Thanks,
Eric
------------Original Message:
Date: Fri, 24 Dec 2010 18:19:41 -0800 (PST)
From: Fred Cisin <cisin at xenosoft.com>
Subject: Re: C64-C128 CP-M Cartridge Interest
<snippage>
It's too bad that nobody brought up CP/M on the Kyoceras (Radio Shack
model 100, Nec 8200, etc). THAT would have been a project.
Or on the Epson RC20!
------------Reply:
As you've read elsewhere Allison did indeed do just that, and some folks in
the Club100 group have also (sporadically) been working on this for a while.
mike
Is there anyone out there that can BURN a 2708 EPROM for me.
My Data I/O System-19 W/UNIPAK is DAS Kaput. It will not burn me a good
prom. Not Sure why though. My Fault ????
I am trying to add some code to Dave Dunfields Monitor to find out why
the 2708 that Andrew burnt is malfunctioning on my N*.
I have tried to add several lines of code but the resulting Prom just
doesn't perform the way the Andrew Prom does.
I am using a SOL-20 System/Bus Probe that will Single Step the N* CPU so
I can then track the code and its execution.
I can see the results of the OUT 3 & 2 Instructions but not the IN 2.
I am going to add jumpers to the Probe to display "Data In" as well as
the existing "Data Out" and that might help.
I have at least 5 2708's and can mail one out then I can sent the Code
as an attachment.
ALSO is there anyone out there using Dave's Monitor Mapped at "0000"
that would be willing to test the 2708 that I have; that works somewhat;
that way I could determine if the Fault is in the N* or in the Code itself.
Since I can't burn a New Prom I am up the creek without a Paddle so to
speak.
TIA
Bob in Wisconsin
C64-C128 CP-M Cartridge Interest
Jim Brain brain at jbrain.com
<mailto:cctalk%40classiccmp.org?Subject=Re%3A%20C64-C128%20CP-M%20Cartridge%
20Interest&In-Reply-To=%3C4D1631AE.3080201%40jbrain.com%3E>
Sat Dec 25 12:02:22 CST 2010
[snip]
Yep. No offense to the list participants, but I gave up on selling
kits. Given the hobbyist nature of my work, kits required too much of
my limited hobbyist time. Given the assembled nature of the unit, I can
use extremely large density devices with no issues.
[snip]
> I am not familiar with the SuperCPU but based on quick web search it
appears
> to be roughly Eurocard sized. Good luck with your project.
It is rather large as well. Though, with today's integration options,
it too could be constructed in the smaller space of a CBM game
cartridge. In fact, it would have to be to bring the cost to something
reasonably. People was apprehensive about a $300.00 20MHz accelerator
in the late '90s, there's no way they'd pay that much now.
Jim
-----REPLY-----
Hi Jim,
I can certainly relate. For the N8VEM project, I have never offered kits
and probably won't ever. All I offer is the PCB, schematics, PCB layout,
and a parts list. I encourage people to make their own boards and only
rarely supply some hard to get parts on an exception only basis. Commonly
available parts are entirely up to the builder to source and supply.
If you have the pre-made PCB and a parts list what is the difference between
that and a kit? You get the PCB and then order the parts from Jameco. Dump
all the parts on your workbench and call it a kit! Read the schematic and
follow the PCB layout. It doesn't get much easier than that!
Making kits is going to eat up all of your time and money with little or no
return and huge frustration. It just isn't practical IMO and can scarcely
be called "homebrew computing" when all the parts arrive in one bag.
Admittedly, using a pre-made PCB is a bit of a stretch too but it is a
reasonable compromise to get more hobbyists involved. I think the PCB is
the biggest barrier to entry (perf board wire wrap, point to point
soldering, or pre-made PCBs) for new hobbyists to homebrew computing.
I certainly wish you the best of luck with your project if you decide to do
it. There doesn't seem to be a huge groundswell of interest here but it is
hard to make any reliable judgement based on comments on CCTALK though.
Maybe spin up a few prototype boards and sprinkle them to some experienced
builders and see what sort of reaction it generates would be a good market
research? That's what I do.
Thanks and have a nice day!
Andrew Lynch
PS, I just got word that one of the N8VEM builder who is lead on the S-100
68K CPU board has completed assembly of the first unit. No test yet but
things are certainly looking good. I am very excited about the S-100 68K
CPU board. Hopefully build and test goes OK and we can release that board
before too long.
FWIW...
From: allison <ajp166 at verizon.net>
> Minimal system:
>
> 8080, 8085, NsC800, Z80, or Z180 cpu. The prefered CPU is z80 as
> it's easy to interface and there are some CP/M apps that require it.
>
> 64K ram, (technically cp/m runs in 20k or more but useful apps are
> minimally 48K)
>
> Boot rom(eprom/flash) that maps out of the 0000h startup address
>
> Mass storage, this can be floppy, CF, SD, Or some form of rom/ram to
> look like disk.
>
> User IO, typically a serial line for a terminal can be a memory mapped video
> and keyboard or similar.
>
For my high school senior project, I designed and built essentially this, significantly over 20 years ago. Z80, 64k RAM (4 x 16Kx8), serial port, simple relocating boot ROM, relevant CBIOS, floppy. I had a TRS-80 4P running Montezuma CP/M (thanks, Dad) to write code on and a random EPROM writer to program 2764s. Got it to boot CP/M in a semester, working an hour or more daily, 5 days a week. I'd also generally figured out how to interface, for local reasons, to STD-Bus for expansion, but never actually implimented it. Had an Intel bubble memory dev kit (128k), but also never got around to it.
Went to college, had Vaxen, 3B2s and early Suns with Unix and C, with a sprinkle of Pascal, Modula-2 & Ada followed by Symbolics and Xerox AI machines. And I relized how much more interested I was in solving big problems than figuring out what problems I could fit into tiny computers, and never looked back. Maybe I'll see if I can find the remaining bits and notes in the basement one day.
Point being, it's an imminently doable project, of variable utility these days, and there's a ton of existing work that can be leveraged.
KJ
Not much of a chance, but I thought I'd try.
Corvus released a special version of the transporter firmware that
went in a piggyback EPROM on the microcontroller.
I've been looking for the code for a LONG time. It is mostly useful
for packet sniffing.
holidays and stuff
Alexandre Souza - Listas pu1bzz.listas at gmail.com
<mailto:cctalk%40classiccmp.org?Subject=Re%3A%20holidays%20and%20stuff&In-Re
ply-To=%3C8ACC14CA48B347038CC2D8CFB528832B%40portajara%3E>
Sat Dec 25 11:52:54 CST 2010
[snip]
> Pics! MSX stuff isn't terribly common here, in my experience.
Well, these are not THE 2.0 I got today, but all photos are mine, with
my old MSXes:
http://msxpro.com/acvs2.0.htmlhttp://msxpro.com/kitddx.htmlhttp://msxpro.com/kitddx2-2p_as.html
And lots of MSX things (most did by me, or by Luciano Sturaro, the owner
of the site):
http://msxpro.com/projetos.html
Of course, there is always my site, with lots of photos:
http://tabalabs.com.br
Want more? :oD
-----REPLY-----
Hi Alexandre,
We are working on an N8VEM home computer design which will be BIOS
compatible with MSX-1. The hardware is somewhat compatible but we are
making some changes due to parts obsolescence, etc. For example replacing
the parallel matrix keyboard with a PS/2 keyboard port, adding IDE, SD, and
floppy controller, etc. One of the builders has demonstrated the MSX CBIOS
using the N8VEM SBC and SCG (sprite color graphics and sound board). That
will be the basis for the new home computer except it will be based on the
Z8S180, 1MB SRAM, 512K Flash ROM, TMS9918 VDP, AY-3-8910, and various IO
ports. The MSX CBIOS is in the MSX BIOS folder.
If you are interested in working on a homebrew MSX computer please stop by
the N8VEM project. There is a folder on the N8VEM wiki called "home
computer" with the schematics and PCB layout. The prototype PCB is in trace
route optimization right now and once some of the other projects clear out I
am planning on a small run of prototype PCBs for initial build and test.
Probably in a couple of months or so.
Thanks and have happy holidays!
Andrew Lynch
C64/C128 CP/M Cartridge Interest?
Jim Brain brain at jbrain.com
<mailto:cctalk%40classiccmp.org?Subject=Re%3A%20C64/C128%20CP/M%20Cartridge%
20Interest%3F&In-Reply-To=%3C4D157503.4070909%40jbrain.com%3E>
Fri Dec 24 22:37:23 CST 2010
[snip]
>
> N8VEM is a good candidate...
A couple of reasons:
* N8VEM, while a great solution, is enormous. There are many closet
C128 CP/M users, and they'd never go for such a huge addition to
their setup. A cartridge form factor, easy decision. Others
would scoff at relegating their C128 as a dumb terminal to another
machine (for instance, they could easily do the same thing by
running a CP/M emu on their PC and connecting the C128 to the PC
via a null modem cable). It's perception.
* There is more to a C128 CP/M cartridge than just using the C128 as
a dumb terminal. Some C128 CP/M apps might take advantage of the
functions in the C128 itself, like the 40 column screen and such.
Thus, memory mirroring and such would be useful. I didn't bring
it up initially, because A) not sure if apps did that. B) I just
wanted to start small, and thought that interfacing the Z80 to the
CBM bus would be a good start
* I theorized that a tiny CP/M board might be of use where N8VEM was
too big or too expansive.
* I so want to start learning Verilog. I thought, if I got a
basic environment going, I could then take a look at virtualizing
the pieces to an FPGA connected to the C128/C64. But, since I
know little of Z80 and CP/M (having used it long ago), I thought
going to FPGAs from nothing was too large a leap.
* The next step after that is an accelerated CP/M. This plays in
with my hope to obtain the rights to the SuperCPU for the
C64/C128. It lacked accelerated Z80/CP/M compatibility, which I
thought I could add, though maybe not.
I'm gathering from the results that there might not be the interest I
had theorized, which is fine. But, I thought I'd at least ask.
Jim
[snip]
-----REPLY-----
Hi Jim,
I gather the form factor you have in mind is the classic C64 game cartridge?
The CP/M cartridge I recall from the 1980's was much larger than a game
cartridge so that's were I was coming from. I've never heard a Eurocard
board (160x100mm) described as "enormous" but clearly you are thinking about
a much smaller board than I was.
I suppose such a cartridge is possible but it would require a few very dense
parts. Probably a CPLD at a minimum probably a FGPA with fine pitch SMT
connections. At least to me, you would need a four chip minimum a Z80,
SRAM, Flash ROM, and glue logic. Maybe less if you can blow a Z80 core into
an FPGA which is possible I believe. All in SMT QFP packaging to get the
density to fit multiple chips into a 2"x3" PCB. It sounds more like a
commercial product than a hobbyist project to me though.
Actually, the C64 ECB bridge approach idea is not using the C64/C128 as only
dumb terminal. It would be 3 or so general purpose IO ports. Then the
C64/C128 could serve IO to the Z80 when it is running. The Z80 sends an IO
request to the C64 which passes status and data back. The 6510 would run an
IO server program and the Z80 would be its client. Assuming an interrupt
driven design the IO processor (6510) could serve the Z80 IO as a
"background" task to a limited extent.
This is how the N8VEM SBC with the 6809/6802/6502 host processor works. The
6809 runs independently but passes its IO requests to the Z80 which serves
terminal IO, disk IO, parallel port, video or whatever. It fully utilitizes
the Z80 and 6809 as a dual independent processors with their own RAM/ROM.
However the 6809 host processor can be optionally upgraded to include its
own unique IO set for more independence or as stand alone mode.
I am not familiar with the SuperCPU but based on quick web search it appears
to be roughly Eurocard sized. Good luck with your project.
Thanks and have a nice day!
Andrew Lynch
PS, we had a builder recently who crafted his own N8VEM SBC using a CPLD
design. Basically it was all the large IC s (CPU, RAM, ROM, UART, PPI) and
one large CPLD. It seemed to work well enough too. I was considering doing
something similar on the N8VEM home computer project since it is limited to
60 square inches. However, we seemed to have resolved the PCB layout issues
using regular PTH DIP/PLCC 2 layer PCB construction.
