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geneb
November 13th, 2011, 04:05 PM
I recently got a Kaypro 10. The drive has a few bad spots on it, and I suspect over time that this will only become worse. Even if a replacement drive could be found, it will still have the age issue going against it.

Are there any projects out there that seriously working on a device that can be plugged into standard MFM drive controllers like those found on the K10 and other vintage machines of the era?


g.

Chuck(G)
November 13th, 2011, 05:26 PM
One of the problems is the cost. What would you be willing to pay?

There is at least one such product out there--the price is over $1K.

geneb
November 13th, 2011, 05:53 PM
...and that's probably while I'll never solve this problem. I would honestly be shocked if there's actually $1k+ worth of components in the device.

It's really frustrating to not having the ability to design the electronics in order to solve this problem all the while knowing that the people that DO have the knowledge can't be bothered.

g.

Chuck(G)
November 13th, 2011, 06:25 PM
It's not that--and my question was serious. There's a lot of work for one of these--most applications just replace the whole controller and drive. Replacing just the drive is quite a bit more complex. If the community of potential users is very small, there would seem to be very little payoff for whoever did all the hard work. Given the number of other projects, how would you convince someone to take the project on?

If this were my Kaypro, I'd find it easier to devise an add-in and patch the BIOS to use it.

geneb
November 13th, 2011, 06:43 PM
The problem with the K10 and other similar-vintage systems is the controller board isn't a separate board - it's designed into the main board of the machine.

As far as I know, there's no drop-in solution for any of these old machines - I seem to recall something of a CPU socket based IDE controller, but there was so little interest, it never went anywhere. This blows my mind, especially with the apparently large population of the vintage computer crowd that could take advantage of this kind of device.

g.

Chuck(G)
November 13th, 2011, 07:49 PM
The problem with the K10 and other similar-vintage systems is the controller board isn't a separate board - it's designed into the main board of the machine.

I don't have a Kaypro 10 in front of me, but I seem to remember that it uses a separate WD1002 controller board connected to the main board by a 40 pin cable. Easy enough to replace that and the hard drive with something that behaves the same. ISTR that the same controller was used in some of the TRS-80 models.

geneb
November 14th, 2011, 02:31 PM
You're correct Chuck, my apologies:

K10 mainboard:
http://www.geneb.org/k10/k10mb.jpg

K10 drive controller:
http://www.geneb.org/k10/k10wd.jpg

It does leave me wondering the practicality of just building some kind of "fake" CF controller that appears to be the old WD controller...Would give life to a lot of systems I think.

tnx.

g.

Chuck(G)
November 14th, 2011, 02:54 PM
You could probably prototype something out using nothing more complicated than an Arduino.

bluethunder
November 14th, 2011, 04:38 PM
The heath H-8/89 guys have come up with a Z-67 drive replacement, that plugs into the existing controller. I don't know what kind of drive was in those Z-67s though.. The vintage would be right for a MFM though.

*** EDIT ***
Turns out the Z-67 is a SASI drive, so probably no use to you... Neat piece of kit though...

http://koyado.com/Heathkit/Z67-IDE.html

madcrow
November 21st, 2011, 06:32 AM
Have you looked at the HxC Floppy Emulator: http://hxc2001.free.fr/floppy_drive_emulator/

It has both FM and MFM modes and seems to be good enough that it will even work in various synthesizers that used disks in a very non-standard fashion. Source code (including VHDL for the hardware bits) seems to be available, so maybe it could be modified to support MFM hard drives.

NobodyIsHere
November 21st, 2011, 08:12 AM
The problem with the K10 and other similar-vintage systems is the controller board isn't a separate board - it's designed into the main board of the machine.

As far as I know, there's no drop-in solution for any of these old machines - I seem to recall something of a CPU socket based IDE controller, but there was so little interest, it never went anywhere. This blows my mind, especially with the apparently large population of the vintage computer crowd that could take advantage of this kind of device.

g.

Hi
On the N8VEM project we did make an "ECB to Z80 socket shim" board. It allows a machine to use an ECB board like DiskIO or PropIO with a pure socketed Z80 machine. In fact it was tested on a Kaypro 10 and a SpectraVideo 728. It seemed to work well however Chuck is right that the BIOS ROM would need to be patched to enable booting from such a device.

I have the PCBs although the project never really took off. It could easily add IDE, CF, SD or whatever to a "non-expandable" Z80 computer using off the shelf components.

http://n8vem-sbc.pbworks.com/w/browse/#view=ViewFolder&param=MINI%20ECB%20to%20Z80%20socket%20adapters

Thanks!

Andrew Lynch

NobodyIsHere
November 21st, 2011, 08:21 AM
...and that's probably while I'll never solve this problem. I would honestly be shocked if there's actually $1k+ worth of components in the device.

It's really frustrating to not having the ability to design the electronics in order to solve this problem all the while knowing that the people that DO have the knowledge can't be bothered.

g.

Hi,

I don't know who if anyone your comment is aimed at but there have been many "hobbyist" projects for with helping vintage computers. For every XT-IDE success there are many "flops" which died for lack of support.

http://www.vintage-computer.com/vcforum/showthread.php?22906-SCSI-1-to-from-IDE-drive-converter

http://www.vintage-computer.com/vcforum/showthread.php?25644-Another-floppy-simulator

and many others, etc

It is easy to say "why don't *they* do something" but it requires resources and time in addition to just skills. In the end, we are the *they*

I recommend to think twice before pointing fingers and declaring what other hobbyists should be doing in their free time as volunteers to make your hobby more enjoyable.

Thanks!

Andrew Lynch

Chuck(G)
November 21st, 2011, 10:02 AM
Have you looked at the HxC Floppy Emulator: http://hxc2001.free.fr/floppy_drive_emulator/

It has both FM and MFM modes and seems to be good enough that it will even work in various synthesizers that used disks in a very non-standard fashion. Source code (including VHDL for the hardware bits) seems to be available, so maybe it could be modified to support MFM hard drives.

I doubt it--the bitrate of an ST506 hard drive is 5Mb/sec--20 times that of a 360K floppy. The logic of the HxC simply doesn't have the horsepower to do this.

However, replacing the WD1002 controller and associated hard drive is easy--the protocol is essentially 8 data bits+3 address bits plus a couple of handshaking bits. Any medium-speed microcontroller can handle that.