Differences between Kaypro II and Kaypro 2?

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dun...@yahoo.com

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Jun 18, 2005, 7:30:03 AM6/18/05
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I noticed a Kaypro 2 for auction on eBay:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=4193&item=5209743159&rd=1&ssPageName=WDVW

and was wondering how this system differs from the Kaypro II?

Will CP/M and Boot system disks for the Kaypro II work on the Kaypro 2?
(and vice versa)

Paul

fugu fred

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Jun 18, 2005, 8:53:52 AM6/18/05
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Looking at the back it looks like it might be a "Kaypro 2X".

I can't help answer your compatibility question but here's some
information that might help.

Slightly edited quotes from old-computers.com : "The Kaypro 2x was one
of the last models Kaypro produced. Size and appearence were the same as
the first Kaypro II, but Internal hardware was inspired by the Kaypro
10. It came with a 4 MHz Z80A processor, dual slimline 400 KB floppy
drives, a built-in 300 baud modem, two serial ports and a full set of
Micropro software (WordStar, CalcStar, DataStar)."

History of the Keypro II/2 names.

"Kaypro II released in 1982, no graphic features, it can display 80 x 24
characters. There are two single-sided / double-density full-heigth
5.25'' disk-drives (190k each).

In 1984 a new Kaypro 2 (refered as Kaypro 2'84) is introduced. It has
two SS/DD half-height floppy drives, a Z-80A running at 4.0 MHz, 2
serial ports and rudimentary graphics (through graphic characters).

The same year, the Kaypro 2X is released. Very similar to a Kaypro 2'84
but with DS/DD half-height drives.

Still in 1984, in order to be compatible with IBM software, a special
version was marketed with an Intel 8088 CPU instead of the Z80A. It was
called the Kaypro II Plus 88!

In 1985 another Kaypro 2 refered as "New 2" is sold. It is basically an
old 2X motherboard, with one or two DS/DD floppy drives, but no 300 baud
modem previously found on the 2X. It comes with just CP/M and Wordstar
for software.

And to spice up a bit things, Kaypro decides to rename its Kaypro 4'84
as Kaypro 2X (sometimes also known as 2X MTC), thus dropping the
previous 2X model!"


So, the "Keypro 2" on ebay could be a Keypro 2'84, a Keypro 2X, a "New
2" or a the later Kaypro 4'84 depending on what's in the box.

Regards,
fugu

dun...@yahoo.com

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Jun 18, 2005, 10:30:05 AM6/18/05
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Yeah, that's pretty confusing. I would be nice if the seller said which
Kaypro it was for sure, and if Kaypro II software (boot disk and CP/M)
was compatible with the unit.

Paul

Randy McLaughlin

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Jun 19, 2005, 7:01:51 PM6/19/05
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<dun...@yahoo.com> wrote in message
news:1119105004.9...@g49g2000cwa.googlegroups.com...

It gets a little confusing but with Kaypro's there are two major factors:

Boot ROM number and whether is Single Sided or Double Sided drives.

At the end if the Kaypro they finally developed a "Universal ROM" where any
changes were transparent since all entry points were fixed.

A Kaypro II is totally different than a Kaypro 2. The earlier computers
(often referred to as 83's) had one type of motherboard and the later
computers (the 84's) had another. The boot ROM from an 83 could not work in
an 84 and vice versa.

As long as you kept the ROM with its corresponding boot disk you are OK. I
am not sure how many different versions there were, Don Maslin knew.

I have several new items including boot disk images to post on my website,
if anyone has boot disks (Kaypro or not) that I don't have please contact me
off list at randy at s100-manuals dot com.


Randy
www.s100-manuals.com


William Hostman

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May 1, 2022, 2:49:29 AMMay 1
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in a word, no.
THis is because CP/M boot disks are machine specific in ways that most later OSs aren't...
There are >= 4 models of "Kaypro 2" and >=2 of "Kaypro II".
The "Kaypro II" is a CP/M focused text-mode only machine. z80, dual floppies in low size, full height. I should have one somewhere. I used it a lot in high school. 1 Serial, 1 Parallel.
The "Kaypro 2" is a CP/M focused text mode machine, but with better characters including graphics characters, better floppies, a faster z80.
The "Kaypro 2X (1984)" is an even more plussed up drives and a second serial port.
The "Kaypro II Plus" is essentially an 8088 version of the Kaypro 2X
The "Kayppro 2X (85)" is a kaypro 4X from 1984, rebadged and repriced. I know that this model sometimes was running MS-DOS; I had to help Friar Kent learn MS-DOS on his after he upgraded from an old 2.

Note that some dealers made motherboard and/or drive replacements available back in the day; I think dad had the roms upgraded on the II. (He upgraded to a 286 not long after... I "upgraded" to an Apple //e...)

Douglas Miller

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May 1, 2022, 8:26:52 AMMay 1
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On Sunday, May 1, 2022 at 1:49:29 AM UTC-5, William Hostman wrote:
> On Saturday, June 18, 2005 at 4:30:03 AM UTC-7, dun...@yahoo.com wrote:
> > I noticed a Kaypro 2 for auction on eBay:
> > http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=4193&item=5209743159&rd=1&ssPageName=WDVW
> > and was wondering how this system differs from the Kaypro II?
> > Will CP/M and Boot system disks for the Kaypro II work on the Kaypro 2?
> > (and vice versa)
> > Paul
> in a word, no.
> >...
Actually, the booting of CP/M versions on Kaypro's depends on (is tied to) the ROM version. Kaypro II/IV had significantly different hardware than all later models, and so the ROMs that could run there are limited. The Kaypro Technical Manual has a table to show ROM versions and compatible CP/M versions.

However, the basic CP/M file format did not change, aside from single/double sided disks/drives. There should be a fair amount of backwards compatibility maintained (you should be able to read files from a Kaypro II disk on a Kaypro 2X system, for example).

Mark Lawler

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May 2, 2022, 11:05:03 AMMay 2
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I used to work at a Kapro dealership while in college doing both programming and repairs on all the models. There was a point in time where there was really no difference between the single sided and double sided floppy machines that shipped from the factory. Okay, there was actually one difference: the jumper settings on each of the drives to select between single sided and double sided. Bought a machine with single sided floppies? Open the case and inspect the drives to see if your free upgrade is simply a matter of moving a jumper on each drive...

Best,
-Mark

Douglas Miller

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May 2, 2022, 6:09:46 PMMay 2
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On Monday, May 2, 2022 at 10:05:03 AM UTC-5, marksl...@gmail.com wrote:
> ... There was a point in time where there was really no difference between the single sided and double sided floppy machines that shipped from the factory. Okay, there was actually one difference: the jumper settings on each of the drives to select between single sided and double sided. Bought a machine with single sided floppies? Open the case and inspect the drives to see if your free upgrade is simply a matter of moving a jumper on each drive...
>
> Best,
> -Mark

That sounds a bit odd to me. I don't recall ever seeing a double-sided drive with a jumper to disable the second head. It was simply up to the computer whether the second head/side was ever selected.

The first-generation Kaypro II mainboard did not even connect to the drive side-select signal, so no matter what drives, ROM, or CP/M you had you would only get single-sided operation.

Starting with the Kaypro II/4 mainboad, side-select was connected and the ROMs all checked media to see if it was (formattted) double or single-sided. If the machine had single-sided drives, you could never detect double-sided (formatted) media. If the machine had double-sided drives, you got double-sided simply by formatting media as double-sided. No jumpers. No crippled features. Kaypro seems to have quickly abandoned single-sided drives, like the rest of the industry, and except for the gen-1 Kaypro II they could seamlessly just build systems with double-sided drives and the capability was automatically detected. My "2X" is likely an example of that: The case says the model is "2" (presumably 2/84) but the back panel has an "X" sticker next to the "2". This would be consistent with it originally being a 2/84 but finally shipped with double-sided drives.

Mark Lawler

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May 2, 2022, 8:02:50 PMMay 2
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May sound odd, but there was a period of time where the owner of the dealership had me cracking open the cases, removing the drives, moving the jumpers on the drives, remounting them, and putting the case back on... The dealer I was employed at? Systems Technology Automated Resources. I saved up and later purchased a Kaypro 4 for myself, using it all through college while still working there.

Best,
-Mark

dxforth

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May 2, 2022, 9:50:08 PMMay 2
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On 3/05/2022 10:02, Mark Lawler wrote:
> ...
> May sound odd, but there was a period of time where the owner of the dealership had me cracking open the cases, removing the drives, moving the jumpers on the drives, remounting them, and putting the case back on...

There were similar stories about memory upgrades for PET computers. Customers
could save money by buying a smaller-memory PET and installing the missing ram
chips themselves as different models began using a common motherboard. There
was even a claim of dealers or factory drilling holes in the motherboard so as
to circumvent that. Strange days indeed.
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