2 Sep
2006
2 Sep
'06
7:49 a.m.
On Sep 1, 2006, at 11:23 PM, cctalk-request at classiccmp.org wrote:
Date: Fri, 1 Sep 2006 18:21:11 -0700 (PDT)
From: "Zane H. Healy" <healyzh at aracnet.com>
My personal advice, get a C64, or maybe a C64c, skip the C128. I'm
saying
this not because I have anything against the C128, but because it
will be
different from what you remember. Plus as has been pointed out, it
does
take up more desktop space.
My "fondness" for the VIC-20 has been replaced with a "fondness"
for the C64
(a machine I hated when I was using the VIC-20, which was through
mid-1986).
I really want to setup my one nice C64 system, I mean I *REALLY*
want to set
it up. Unfortunatly I don't have the space, and truth be told, the
time. I
also really want to setup an Apple // of some sort, most likely a //
gs, but
there is the same problem.
I need to find a really good excuse to set up one or the other, and
so far I
haven't found one.
Zane
I agree with this, the C64 or a 64C (I had both) represent the height
of Commodore 8-bit, though I have always wanted a 128D. There are
supposedly "mint" in box examples of these on eBay right now. VIC-20
too. The 128 does have the Z-80 for CP/M though, if that interests you.
David
DavidGreelish
classiccomputing.com
The Home of Classic Computing Podcast
and Computer History Nostalgia
2 Sep
2 Sep
10 a.m.
On Saturday 02 September 2006 10:49 am, David Greelish wrote:
Back in the day when I worked on a lot of this stuff, I saw a fair number of
both CP/M boxes and c= stuff, and one time did actually take a few minutes
and boot CP/M on a 128/1571 combo. It ran, and I was able to take some of
the software that I was used to running on other platforms and run it there,
but I was not all that impressed with the way it ran-- it was slow.
People should also be aware of the misleading stuff in the way the speed of
that part is presented. They called it "a 4 MHz Z80" but even though it was
indeed that chip the way they had it configured in there was so tightly
coupled with the rest of the system that it only ran some of the time,
rather than all of the time, giving an effective clock rate of somewhere
around 2.5 MHz.
--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, a critter that can
be killed but can't be tamed. --Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin
> I also really want to setup an Apple // of some
sort, most likely a //
> gs, but there is the same problem.
Hm, I just happen to have a IIgs system I'm not doing anything with...
I need to find
a really good excuse to set up one or the other, and
so far I haven't found one.
Zane
I agree with this, the C64 or a 64C (I had both) represent the height
of Commodore 8-bit, though I have always wanted a 128D. There are
supposedly "mint" in box examples of these on eBay right now. VIC-20
too. The 128 does have the Z-80 for CP/M though, if that interests you. 
11:17 a.m.
Back in the day when I worked on a lot of this stuff,
I saw a fair number of
both CP/M boxes and c= stuff, and one time did actually take a few minutes
and boot CP/M on a 128/1571 combo. It ran, and I was able to take some of
the software that I was used to running on other platforms and run it there,
but I was not all that impressed with the way it ran-- it was slow.
Part of that was the software implementation, however. A number of people have
rewritten portions of the BIOS/BDOS and made some decent speed gains.
Mind you, I think I've used my 128 in its CP/M capacity exactly twice.
--
--------------------------------- personal: http://www.armory.com/~spectre/ ---
Cameron Kaiser * Floodgap Systems * www.floodgap.com * ckaiser at floodgap.com
-- Los Angeles 2001: "Ohmigosh, it's full of *cars!*"
-------------------------
8:56 p.m.
Roy J. Tellason wrote:
People should also be aware of the misleading stuff in
the way the speed of
that part is presented. They called it "a 4 MHz Z80" but even though it was
indeed that chip the way they had it configured in there was so tightly
coupled with the rest of the system that it only ran some of the time,
rather than all of the time, giving an effective clock rate of somewhere
around 2.5 MHz.
Misleading it was, though we should assign blame to the Marketing folks.
When the C128 was being developed, Marketing wanted to hit the business
market (they had tried to position the Plus/4 there and failed).
Someone remember the old C64 CP/M cartridge and decided to play that up
(the C128 was C64 compatible, they reasoned, so the CP/M cart could be
used to offer CP/M support).
The problem was, the CP/M cart sucked, and would only work on the
earliest models of the C64. It was a direct copy of the Apple CP/M
cart, according to some reports, but didn;t take into account the
specifics of the C64 expansion port.
Brian Bagnall documents the specifics in his book, but in general, Bil
Herd got the CP/M cart to work by "accidentally" designing the Z80 into
the motherboard.
However, as the design-in was accidental, there was little time (or
ability) to do a proper design-in. If it had been a sanctioned design,
the full 4MHz would have been offered (and probably more), but CBM was
cheap, and Bil was trying to hit a mandated requirement, not a speedy
CP/M design.
Although the book does not document it, I think Bil had to fight tooth
and nail to keep the accidental work in place.
However, as Bil later notes, the Z80 ended up saving the CBM bacon, as
it was used to deal with badly misbehaving cartridges that did funky
things with the C64 MMU lines, which the C128 could not deal with on
machine startup. Thus, the Z80 actually starts the C128 up, and then
passes control to the 8502 (6502/10 compatible) CPU.
Jim
3 Sep
3 Sep
10:09 a.m.
On Saturday 02 September 2006 11:56 pm, Jim Brain wrote:
Roy J. Tellason wrote:
Oh really? I was wondering what they were trying to do there. I was also of
the impression that the +4 was supposed to be a replacement for the c64, and
that the c16 (which I think I may have seen _one_ of perhaps) was supposed to
replace the vic20. But I'm not really sure.
People should also be aware of the misleading
stuff in the way the speed
of that part is presented. They called it "a 4 MHz Z80" but even though
it was indeed that chip the way they had it configured in there was so
tightly coupled with the rest of the system that it only ran some of the
time, rather than all of the time, giving an effective clock rate of
somewhere around 2.5 MHz.
Misleading it was, though we should assign blame to the Marketing folks.
When the C128 was being developed, Marketing wanted to hit the business
market (they had tried to position the Plus/4 there and failed). Someone remember the old C64 CP/M cartridge and
decided to play that up
(the C128 was C64 compatible, they reasoned, so the CP/M cart could be
used to offer CP/M support).
I read somewhere that the CP/M cartridge never actually worked all that well.
If it worked at all.
The problem was, the CP/M cart sucked, and would only
work on the
earliest models of the C64. It was a direct copy of the Apple CP/M
cart, according to some reports, but didn;t take into account the
specifics of the C64 expansion port.
I have the 64's service manual around here someplace, and maybe I should look
at the differences between the various boards, I don't remember anything in
particular there that would account for this. I do remember a couple of
lines of that port being labeled "Z80" and "DMA", which I never saw
anything
use.
Brian Bagnall documents the specifics in his book, but
in general, Bil
Herd got the CP/M cart to work by "accidentally" designing the Z80 into
the motherboard.
However, as the design-in was accidental, there was little time (or
ability) to do a proper design-in. If it had been a sanctioned design,
the full 4MHz would have been offered (and probably more), but CBM was
cheap, and Bil was trying to hit a mandated requirement, not a speedy
CP/M design.
Although the book does not document it, I think Bil had to fight tooth
and nail to keep the accidental work in place.
However, as Bil later notes, the Z80 ended up saving the CBM bacon, as
it was used to deal with badly misbehaving cartridges that did funky
things with the C64 MMU lines, which the C128 could not deal with on
machine startup. Thus, the Z80 actually starts the C128 up, and then
passes control to the 8502 (6502/10 compatible) CPU.
I also have the 128 manual on hand as well, but never really dug into the
workings of that MMU chip. As a service center and wanting to have a
complete set of spares on hand I did get a hold of some of those, and some
of the PLA chips that were used in the 128, as well as a number of the parts
peculiar to the 1571, and ended up never using any of them. I don't know if
they'd be useful in anything else offhand.
--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, a critter that can
be killed but can't be tamed. --Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin
4 Sep
4 Sep
1:39 p.m.
Roy J. Tellason wrote:
Oh really? I was wondering what they were trying to
do there. I was also of
the impression that the +4 was supposed to be a replacement for the c64, and
that the c16 (which I think I may have seen _one_ of perhaps) was supposed to
replace the vic20. But I'm not really sure.
Originally, it was designed to replace the C116, to hit the TS1000 price
point. Jack wanted a CBM in every house. It was designed in Japan, and
eventually mutated into the C116. For the same price as Clive's TS1K,
it had color and ran a bit faster.
Then, and reports vary as to why, CBM tried to beef it up into an entire
product line. It was designed for absolute low parts count (the design
puts VIC-like sound back in the video, it lacks sprites, etc.) The
CV364 (with the speech synthesizer) would be the top end, with the 264
coming in second. Cameron can provide more detail on when the C16 (116
spec in a VIC/64 case) was added, I think it came later in the process.
In any case, they they then recruited Jim Butterfield to intro the units
at CES 1984. Jack told me he went to the prep meeting, and saw the
machines. He thought they were all nice to fit below the 64 in the
product line. They then informed him that they didn;t want to
cannibalize 64 sales, so they were positioning the +4 series as a
premium business product. Jim thought that was a dumb idea. It tanked,
as it should have.
Herd relates going around during the 84 show and vendors were yelling at
him about the units being incompatible. He assured them not too worry
about porting SW to the unit, as it would die. This is why he fought
hard for the C128 to be compatible with "something"
And the little C116 that originally held so much promise? A small
production was dumped in Japan, where they were not received all that
well. Mine is a prototype unit, which is why it is NTSC. Either
Cameron or Bo Zimmerman has a production unit, which I think is PAL.
I read somewhere that the CP/M cartridge never
actually worked all that well.
If it worked at all.
Correct. Bil Herd notes that the design didn;t fully tristate the
busses, which it needs to do for the VIC to work.
I have the 64's service manual around here
someplace, and maybe I should look
at the differences between the various boards, I don't remember anything in
particular there that would account for this. I do remember a couple of
lines of that port being labeled "Z80" and "DMA", which I never saw
anything
use.
Bil hangs out in comp.sys.amiga.* at times, maybe you can email him.
I've heard from numerous folks that on early boards work, but I never
cared enough to determine why.
I also have the 128 manual on hand as well, but never
really dug into the
workings of that MMU chip. As a service center and wanting to have a
complete set of spares on hand I did get a hold of some of those, and some
of the PLA chips that were used in the 128, as well as a number of the parts
peculiar to the 1571, and ended up never using any of them. I don't know if
they'd be useful in anything else offhand.
Well, technically, I'm talking about the ROMH, ROML, EXROM, etc. lines
of the 64, which would change the memory map. The IC controlling them
is the PLA. Calling it an MMU (given the current usage of the term) is
probably misleading. The C128 has a better attempt at an MMU, where
memory can be programmatically remapped. IN essence, the EXROM, ROMH,
ROML were only intended to be changed upon powerup, but on the 64, they
could be changed at any time to affect the memory map. Some carts would
use this to an advantage. The C128 had issues with this usage of the lines.
Jim
2:05 p.m.
Then, and reports vary as to why, CBM tried to beef it
up into an entire
product line. It was designed for absolute low parts count (the design
puts VIC-like sound back in the video, it lacks sprites, etc.) The
CV364 (with the speech synthesizer) would be the top end, with the 264
coming in second. Cameron can provide more detail on when the C16 (116
spec in a VIC/64 case) was added, I think it came later in the process.
It was a pretty late add in the 264 line. My best guess is Q1 1985.
Here are some more notes on the 264 series:
http://www.floodgap.com/retrobits/ckb/secret/x64.html
And the little C116 that originally held so much
promise? A small
production was dumped in Japan, where they were not received all that
well. Mine is a prototype unit, which is why it is NTSC. Either
Cameron or Bo Zimmerman has a production unit, which I think is PAL.
I have a PAL production unit, but it was converted to NTSC by its previous
owner (a Kernal and crystal swap are all that's necessary; a Kernal from an
NTSC 16 will do nicely); I demoed it at VCF a couple years back.
I hate the 116 keyboard -- it's bad even amongst chiclet keyboards.
Well, technically, I'm talking about the ROMH,
ROML, EXROM, etc. lines
of the 64, which would change the memory map. The IC controlling them
is the PLA. Calling it an MMU (given the current usage of the term) is
probably misleading. The C128 has a better attempt at an MMU, where
memory can be programmatically remapped. IN essence, the EXROM, ROMH,
ROML were only intended to be changed upon powerup, but on the 64, they
could be changed at any time to affect the memory map. Some carts would
use this to an advantage. The C128 had issues with this usage of the lines.
The Magic Voice comes to mind ...
--
--------------------------------- personal: http://www.armory.com/~spectre/ ---
Cameron Kaiser * Floodgap Systems * www.floodgap.com * ckaiser at floodgap.com
-- NO, I'M NOT AN ELITIST...WHY DO YOU ASK, PEASANT? -- Rusty Spoon -----------
2:17 p.m.
On Monday 04 September 2006 04:39 pm, Jim Brain wrote:
Just to clarify, if we're talking about the 128, there was both the 8721 PLA
in there _and_ the 8722 MMU (I hope I got those numbers right).
I also have
the 128 manual on hand as well, but never really dug into
the workings of that MMU chip. As a service center and wanting to have a
complete set of spares on hand I did get a hold of some of those, and
some of the PLA chips that were used in the 128, as well as a number of
the parts peculiar to the 1571, and ended up never using any of them. I
don't know if they'd be useful in anything else offhand.
Well, technically, I'm talking about the ROMH, ROML, EXROM, etc. lines
of the 64, which would change the memory map. The IC controlling them
is the PLA. Calling it an MMU (given the current usage of the term) is
probably misleading. The C128 has a better attempt at an MMU, where memory
can be
programmatically remapped.
Ok, this makes it look like you were referring to the 64 above, which I was
not. When I said "MMU" I was talking about the 128 only.
IN essence, the EXROM, ROMH, ROML were only intended
to be changed upon
powerup, but on the 64, they could be changed at any time to affect the
memory map. Some carts would use this to an advantage. The C128 had issues
with this usage of the lines.
Gotcha.
--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, a critter that can
be killed but can't be tamed. --Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin
3:09 p.m.
I read
somewhere that the CP/M cartridge never actually worked all
that well. If it worked at all.
Correct. Bil Herd notes that the design didn;t fully tristate the
busses, which it needs to do for the VIC to work.
> I have the 64's service manual around here someplace, and maybe I
> should look at the differences between the various boards, I don't
> remember anything in particular there that would account for this. I
> do remember a couple of lines of that port being labeled "Z80" and
> "DMA", which I never saw anything use.
> 
2 Sep
2 Sep
11:36 p.m.
At 1:00 PM -0400 9/2/06, Roy J. Tellason wrote:
Trust me, lack of systems isn't my problem. I have 1 //+, 2-3 //e's,
2-3 //c's, and 2 //gs's (including one with SCSI) :^) Lack of space
(and time) is my problem.
> I also
really want to setup an Apple // of some sort, most likely a //
> gs, but there is the same problem.
Hm, I just happen to have a IIgs system I'm not doing anything with...
> > I need to find a really good excuse to set up one or the other, and
> > so far I haven't found one.
> >
> > Zane Back in the day when I worked on a lot of this stuff,
I saw a fair number of
both CP/M boxes and c= stuff, and one time did actually take a few minutes
and boot CP/M on a 128/1571 combo. It ran, and I was able to take some of
the software that I was used to running on other platforms and run it there,
but I was not all that impressed with the way it ran-- it was slow.
I've had it running on my C128, I wasn't that impressed either. If I
want to run CP/M, I'll break out my Kaypro II.
Zane
--
| Zane H. Healy | UNIX Systems Administrator |
| healyzh at aracnet.com (primary) | OpenVMS Enthusiast |
| MONK::HEALYZH (DECnet) | Classic Computer Collector |
+----------------------------------+----------------------------+
| Empire of the Petal Throne and Traveller Role Playing, |
| PDP-10 Emulation and Zane's Computer Museum. |
| http://www.aracnet.com/~healyzh/ |
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9 comments
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dgreelish＠mac.com -
healyzh＠aracnet.com -
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