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8032-sk keyboard mod?

E

Elvi

Experienced Member
Joined
Nov 23, 2011
Messages
275
Location
Munsala, Finland
is there anyway to take a more modern keyboard like say a din or ps/2 variant and mod it so it would work for the 8032-sk?
i'm missing the keyboard for this computer so that's why i'm asking.
 
Hi Elvi,

I have something that may help you,
It's a microcontroller circuit that reads from a PS/2 keyboard and outputs characters in parallel ascii, which I believe is close to what the PET keyboards do. I'll check to see if I can find some specifics about this. What type of connector is on the PET for the keyboard?
 
Ok, just checked a PET schematic here:
http://www.zimmers.net/anonftp/pub/cbm/schematics/computers/pet/2001N/320349-3.gif

Looks like the "KIN" is a keyboard row number presented by the PIA chip. Then the keyboard presents its data on D0-7. I'm not sure what "DIAG" is yet.
Appears to not be terribly complicated so I can modify the PS2-ASCII circuit to handle this. I'm guessing that the 8032SK keyboard is the same as the regular 8032 keyboard, someone please correct me if not. When I get a chance I'll dig out the PS2 adapter and hack around with it.
 
Yes, the 8032-SK keyboard is identical to a 8032 keyboard. The DB25 is wired 1:1 compared to the internal connector, possibly with a few pins unused. I once made an "adaptor", using a spare 8032 keyboard with a 8032-SK computer.
 
Great, then it shouldn't be too difficult to modify my PS2-ASCII adaptor to work with a PET. I'll take a look and keep you posted..
 
gubbish said:
Great, then it shouldn't be too difficult to modify my PS2-ASCII adaptor to work with a PET. I'll take a look and keep you posted..
Click to expand...
It might not be as easy as you think, but I'm certainly very interested to see how you make out; I've been thinking of building something similar with oldskool TTL & EPROMs.

I'm not sure what the current status is, but Jim Brain sells a unit like this:

http://store.go4retro.com/c-key-keyboard-adapter/

AFAIK it works, but the firmware isn't quite there and it's not conveniently programmable so he's working on a better (USB) version.

FWIW he also sells a PS/2 to ASCII parallel/rs-232 encoder like yours:

http://store.go4retro.com/ps-2-keyboard-encoder/

Good luck; can't wait to see how it goes.

mike
 
Thanks Mike,

the c-key adapter actually looks like it would do most of what we're talking about - it doesn't mention support for PET and I'm not sure if the commodore keyboards are the same on C64/128 and PET..
There will undoubtedly be a few gotchas in building this but that's all part of the fun..

Always useful to have some PS2 to ASCII converters around, due to the frequency of old computers with bum keyboards. Keyboard restoration is fun but time consuming, sometimes you just want to see some characters on the screen.

Will keep ya posted..
- Mike
 
The pet machines have a simple passive 8x10 key matrix. It does not use any form of ASCII output. Basically the row is selected using a 4 bit binary number, which is fed to a 4-to-10 decoder to select one of the 10 rows. Then the 8 columns are read at the same time to determine which keys are down. There were two different versions - graphic and business. Most 40 column pets used the graphic keyboard and 80 column pets used the business keyboard.

The keyboard matrix is in the pet editor rom. It is possible to connect almost any passive matrix keyboard (like the c128d or c64 keyboard) but you would need to modify the rom for the correct matrix. A ps2 to ASCII converter will not work unless you re-write the keyboard scanning routines in the editor rom. A ps2/USB keyboard to matrix converter will work if modified to support the pet matrix.

Steve

Steve
 
Thanks Steve,

Very useful info,
Basically I'll be able to use the PS2 part of the code for the PS2-ASCII converter to read from the PS2 keyboard, but will need to change the output part. Basically ASCII will be replaced with the PET keyboard matrix, and it will need to read the row number from the KIN inputs. Looks like we would also need a switch to select what keyboard we want to emulate, business or graphic.. This could be expanded to work as an emulator for most any passive matrix keyboard, if desired.
 
lol all this is allready going over my head, sounds like it's more hassle than it's worth, would be easier to find a 8032 or -sk keyboard... someday.
 
Haha, no worries. Due to my own obsessive nature I'll most likely go forward with building a PS2-to-PET keyboard adapter, since I've been wanting to do that anyway.. I'm hoping to use a spare PET motherboard to make a porta-PET at some point and using a PS2 keyboard would be nice.
I'll keep you notified on progress, thanks!
- Mike
 
I've been pondering building a portable pet myself. I was thinking of using an 8296D motherboard, with a composite video adapter connected to an LCD. The keyboard could be the tricky part... I'd love to see anything you come up with! Oh, and using a PETDISK for storage of course! ;-)

Steve
 
sjgray said:
I've been pondering building a portable pet myself. I was thinking of using an 8296D motherboard, with a composite video adapter connected to an LCD. The keyboard could be the tricky part... I'd love to see anything you come up with! Oh, and using a PETDISK for storage of course! ;-)

Steve
Click to expand...
Hi Steve, and happy 2012!
Do you mean portable as in battery powered, or portable as in small enough to carry?
And why's the keyboard a problem? Just do what Carlsson did.

I think in Jim's original version he actually used a matrix switch IC, and when I did something similar years ago I just used an EPROM, but I'm sure Gubbish can bring it all down to a $5.00 8-pin IC somehow... ;-)
 
I've been pondering building a portable pet myself. I was thinking of using an 8296D motherboard
Click to expand...

If you do this, you should be using a ram/rom replacement board on it to reduce heat/power usage. Mine runs alot cooler after I removed all the ram and roms.

Later,
dabone
 
MikeS said:
Hi Steve, and happy 2012!
Do you mean portable as in battery powered, or portable as in small enough to carry?
And why's the keyboard a problem? Just do what Carlsson did.

I think in Jim's original version he actually used a matrix switch IC, and when I did something similar years ago I just used an EPROM, but I'm sure Gubbish can bring it all down to a $5.00 8-pin IC somehow... ;-)
Click to expand...

I was thinking just plug-in but portable. The 8296D uses a 5V and 12 V switching supply and so has no ugly big capacitors on the motherboard. The motherboard is the smallest and latest and could be powered by one of those small/light/cheap external supplies (5V@2A, 12V@2A...about $5 on ebay). I've never looked into battery power options.

I figured I could mount the motherboard behind a 15" LCD and use an external keyboard. It would look much like an iMac or the new all-in-one pc's.

The PET keyboards are very bulky. They use full-travel keys and are very thick. Compare that to the SX64 keyboard which is thin and light, much like modern keyboards. Connecting a new pc-style keyboard would be nice... even wireless would be cool.

I have lots of these silly ideas and it always comes down to making a proper case for it. I just don't have the skills to do metal-work or some type of plastic case.

Steve
 
dabone said:
If you do this, you should be using a ram/rom replacement board on it to reduce heat/power usage. Mine runs alot cooler after I removed all the ram and roms.

Later,
dabone
Click to expand...

I was not aware that the 8296D motherboard was power-hungry. After all it does use a minimum of parts, using late-80's components, although I suppose 16 pieces of 80's ram would be hotter than 1 replacement 2000's ram chip.

Steve
 
carlsson said:
How about a SX-8296D? :) In the same spirit someone at Commodore once made a SX-500 prototype, i.e. an Amiga 500 in a SX-64 shell.
Click to expand...

That would be cool to see. The main problem i think is motherboard size. The SX-64 had re-designed boards made to be long and thin. I suppose if you replaced the CRT with an LCD and mounted the floppy drive on the top bay that would leave room on the bottom for a full-size pet motherboard. I think an SFD-1001 drive might fit in there with a little work... I do have a couple spare SX cases and a 6" LCD.... hmmm ;-) Still, the keyboard would be tricky.

Steve
 
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