macplus keyboard<->PS/2

[Bolle]

hi!

i found this on myoldmac.net:

Hello to all pre-ADB Mac Users, I like to announce an open source, open hardware keyboard protocol

adaptor project to connect the MacPlus keyboard protocol and PS2.

With this adaptor, you can connect your original MacPlus-keyboard

to your PeeCee, or you can take a mass-production-PS2-keyboard

to run your MacPlus, if the original keyboard is lost or broken.

The Hardware is based on an low-cost AT89C2051 8051 type

microcontroller and will fit for both, translation from

a PS2-Keyboard to a MacPlus Computer or vis versa from

the MacPlus Keyboard to a PS2-Host.

Note: do not use telephone-headset-cables as keyboard cable!

telephone cables are connected in roll-over mode

while the mac-keyboard cable is straigt-through.

There are two firmware versions available:

kbdbabel_ps2_macplus_8051.asm from PS2-keyboard to the Mac

and

kbdbabel_mac_ps2_8051.asm from the MacPlus keyboard to PS2.

Note: if you want to switch the direction on the adaptor,

you need to change or re-program the micronontroller.

Note2: This adapter may be used as well for Mac 512k / Mac 128k,

when some adaptions on the scancode translation table are made.

Sorry, I did not get my hands on a Mac512k/Mac128k keyboard

to analyze the protocol.

Some documentation about the Mac Plus Keyboard protocol

is available as well (draft, germand keyboard)

http://kbdbabel.sourceforge.net/doc/kbdbabel_dev_doc_macplus_20070606.pdf

Schematic, PCB mask and firmware source code is available here

http://kbdbabel.cvs.sourceforge.net/*checkout*/kbdbabel/kbdbabel/kbdbabel-mac-ps2/89c2051-mac-ps2_sch.eps

http://kbdbabel.cvs.sourceforge.net/*checkout*/kbdbabel/kbdbabel/kbdbabel-mac-ps2/89c2051-mac-ps2_pcb.eps

http://kbdbabel.cvs.sourceforge.net/*checkout*/kbdbabel/kbdbabel/kbdbabel-mac-ps2/kbdbabel_mac_ps2_8051.asm

http://kbdbabel.cvs.sourceforge.net/*checkout*/kbdbabel/kbdbabel/kbdbabel-mac-ps2/kbdbabel_ps2_macplus_8051.asm

The open software is licensed under the terms of the GNU GPL,

schematics and designs under Creative Commons CC-BY-SA 2.5.

More information, and other keyboard adaptors can be found on

www.kbdbabel.org

cu from Cologne, Alexander / kbdbabel

 

[funkytoad]

Wow!

This could be really helpful, as I am trying to find a Mac Plus Keyboard... But I may not have to right away.

Thanks!

-funkytoad

 

[Bunsen]

You know, I opened up a point of sale keyboard a while back, and it had a reflashable ATxxxx microcontroller in it.

 

[Scott Baret]

Yay, a Model M on my Mac Plus!!!

 

[macclassic]

Buyer beware funkytoad, I just bought a "used" Mac Plus keyboard and had to repair 12 of it's keyswitches, but it's OK now.

 

[nahuelmarisi]

sounds great, more so to connect my mac plus keyboard (i really love it) to other computers.

 

[Mac128]

I'm not sure I get this. I looked around the website and can't seem to find any schematics from which to build the adapter. I would assume that I have to find a way to flash the chip with the downloaded code? Definitely not for the casual user.

Theoretically, one could with this adapter create a Mac Plus to PS-2 adapter, then use a PS-2 to USB adapter to connect the Mac Plus keyboard to a Modern Mac. So it has some very exciting applications.

Am I missing something here?

 

[equant]

I'm not sure I get this. I looked around the website and can't seem to find any schematics

Follow the sourceforge link and browse the CVS...

http://kbdbabel.cvs.sourceforge.net/kbdbabel/kbdbabel/kbdbabel-mac-ps2/

The hardware looks pretty easy to build by hand. It uses a Atmel AT89C2051 which uses the 8051 instruction set and is in circuit programmable.

So, not nearly as hard as it could be.

Nathan