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Bungo Pony
September 17th, 2016, 02:51 PM
33202

So I decided to try tackling the badly abused Kaypro 10. The thing turns on but doesn't display anything. After looking around a bit, someone was obviously hacking away in it. They tried modding it to take a 3 1/2" floppy drive, the Z80 was missing, and they chopped off the header to connect the hard drive.

I swapped the mother board in from my Kaypro II and verified that the power supply is good, and the screen works.

I'm highly suspecting that the Eprom in the picture is not original after comparing pictures on the Internet. I have no clue what this mod is, but I'd love some verification that it's not a real mod and would like to know the purpose of the Eprom. I don't have the ability to burn an Eprom, so I may need to request services from someone, if possible.

Randy McLaughlin
September 17th, 2016, 08:19 PM
There are several sites with Kaypro disk and ROM images like:

http://www.retroarchive.org/maslin/roms/kaypro/index.html

Be sure it's the Z80 that's missing and replace with Z80A or better (4MHZ or better).

To repair messed up hard drive connector - remove the plastic spacer that holds the pins straight will soldering - then heat up one pin at a time and pull out. Use solder wick or solder sucker to clear holes.

There are two motherboards used on Kaypro 10's - the original had no modem - just one four pin phone type connector for keyboard (handset side not phone line size - ie small 4 pin). They newer board - a universal board used in all Z80 Kaypro's at the end had a real-time clock and modem - if it has a battery on it it's for the clock - newer board and remove and the battery before it corrodes the board.

There were lots and lots of ROM's used for Kaypro's - just by non-linear systems, the lots more that were third party. You would have to dump the ROM and look for text in it to know what it's for.


Randy

Bungo Pony
September 17th, 2016, 08:46 PM
Be sure it's the Z80 that's missing and replace with Z80A or better (4MHZ or better).

That may be my error. I stuck a plain ol' Z80 in there. If my Kaypro II has a Z80A, I'll borrow it for testing purposes.


There are two motherboards used on Kaypro 10's - the original had no modem - just one four pin phone type connector for keyboard (handset side not phone line size - ie small 4 pin). They newer board - a universal board used in all Z80 Kaypro's at the end had a real-time clock and modem - if it has a battery on it it's for the clock - newer board and remove and the battery before it corrodes the board.

Mine has no battery, so I guess it's an old style board.


There were lots and lots of ROM's used for Kaypro's - just by non-linear systems, the lots more that were third party. You would have to dump the ROM and look for text in it to know what it's for.

It's getting closer to the point where I should invest in an Eprom burner. I had access to one at my old workplace, but that's absolutely no use to me now :D

I'm guessing someone put something that's third party into the socket since it's a hacked up Eprom with some wiring mod. I'll try the Z80A fix before I start going into burning ROMs.

The floppy drive also doesn't spin, but I'm guessing that's likely a belt issue.

There's also currently no hard drive, but I'll cross that bridge when I get to it. I have some old hard drives kicking around here that should work.

Randy McLaughlin
September 17th, 2016, 08:55 PM
The floppy drive also doesn't spin, but I'm guessing that's likely a belt issue.

There's also currently no hard drive, but I'll cross that bridge when I get to it. I have some old hard drives kicking around here that should work.

The Kaypro 10's Floppy drive was usually direct drive and had no belt. Any PC compatible drive that fits will work, including a 3.5" drive.

The Kaypro 10 uses an MFM drive and has two boards to connect it: The first board is 50 pin to 40 pin and has an address decode to select the next drive 40 pin WD to MFM controller.

If you don't have both these boards then what you have is a floppy based computer.


Randy

Bungo Pony
September 18th, 2016, 03:34 AM
Thanks for your insight.

I was kinda wondering about the hard drive controller. From what I can tell, this is the board that I need to have:

http://www.nightfallcrew.com/wp-content/gallery/non-linear-systems-inc-kaypro-10/IMG_1505.jpg

...and it's not in there. I suppose this Kaypro is just going to sit as a parts computer for the time being until I find another one, or a controller card. My Kaypro II works wonderfully, so I don't really need another floppy-based system.

Too bad :(

Randy McLaughlin
September 18th, 2016, 09:22 AM
Thanks for your insight.

I was kinda wondering about the hard drive controller. From what I can tell, this is the board that I need to have:

http://www.nightfallcrew.com/wp-content/gallery/non-linear-systems-inc-kaypro-10/IMG_1505.jpg

...and it's not in there. I suppose this Kaypro is just going to sit as a parts computer for the time being until I find another one, or a controller card. My Kaypro II works wonderfully, so I don't really need another floppy-based system.

Too bad :(

A kaypro 10 without a hard disk is basically a Kaypro 4'84. It is possible to getting it running as a floppy based system.

The WD controller is very well documented and uses a simple 8 bit interface. If you have the technical skills do what I recommended before - make an emulator:

Using a micro controller make an SD card WD clone - the SD card works with a simple SPI interface that micro-controllers interface to directly. I would use a 40 pin pic so I hade plenty of extra pins for expansion. I would use a pic with at least 32K of program RAM and a few K of RAM so whole sectors can be held in RAM.

Pics can be programmed in ASM, Basic, or C - pick your pic poison ;-)

Start simple and just use first 32K of SD as the hard disk.

Later use the free FAT code to make the hard disk just an image file on a fat disk to make it easy to use a PC.

It should be able to be done in a weekend or two.

Cost for bare parts in $20.00 range - Wiring minimum - Cost of Pic programmer another $20-$80 depending on if you just want to program pics or also handle other devices.

Personally I would include the 50 pin to 40 pin adapter board arranged to it could connect straight to the Kaypro motherboard but easily not include the address decoding circuitry so other WD based older systems could use it also with a 40 pin connector. There were thousands of the WD controllers sold and used in lots of 70's and 80's computers.

My plate is full but I had an interest in doing it myself and I have all the PDF documentation needed.


Randy

Bungo Pony
September 18th, 2016, 03:38 PM
I'm not willing to put that much work into the Kaypro since I haven't even got the motherboard functioning yet. I have a lot of other computers around here that need less work on them (the Amiga 2000 is high priority on my list) and I'd rather put the time into them to get them functioning at 100%.

I'm going to keep my eyes opened for another HD-based Kaypro though. I had a lot of fun restoring the Kaypro II that I unexpectedly ended up with.

geneb
September 20th, 2016, 07:17 AM
You can connect a FreHD via a small adapter board to the controller connection on the K10 motherboard.

g.