PC Keyboard to Amiga Adapter

hardware redesign by Martin Clausen (mc AT rotgradpsi DOT de), development featured by Rolands Amiga

This is a adapter to connect a PC-keyboard to any Amiga. This is not programmed by me, I just made some modifications. Thanks to the authors who I do not know and I could not contact. It was freeware and it will stay freeware. I hope that is okay.

Table of contents:


Some strange key mapping

left windows left Amiga
right windows right Amiga
windows menu left Amiga m (cycle screen)
right or left control Control

the interface will send rawkey codes for these xtra keys as follow:

home 75
end 76
pageUp 77
pageDown 78
F11 79
F12 7a
printScreen 7b
scrollLock 7c

So you could use an external program to bother with these codes.

Generation of a reset after a programmable delay

With this release the interface has the ability to perform a reset after a programmable delay. Why? For those who, have some hard drive spin up problem. The port P3 is a 8 bit register that define the duration of the delay.

If you leave P3 unconnected nothing happens. If you tie low the P3.5 the delay before a reset will be 32 * 70ms. All the pins of P3 at gnd and the delay will be 255 * 70ms that's too much!

Circuit Description

J2: solder the 5 lines of Amiga (kbClock, KbData, KbReset, 5 V, NC, GND) J1: wire a DIN 5 female to plug the PC-keyboard like this:
front view   NOT solder view

/--v--\   1 = KBClk
|3   1|   2 = KBDat
| 5 4 |   3 = NC
|  2  |   4 = Gnd
\_____/   5 = +5v

At some A500 manuals pin 1 and 2 of the keyboard connector are swapped!! *arrrgrrrr* In this case you will get a lot of ''''''''' even without a keyboard!

Keep in mind that the AT89C2051 has no pullups at P1.0   P1.1 so pull P1.0 and P1.1 to GND

Signals are available at:

Amiga Clock P1.3
Amiga Data P1.4
Amiga Reset P1.5
Keyboard Clock P1.6
Keyboard Data P1.7


Download of Program and Circuit

The part description in schematics is read as follows:
part type + value in exponential form + package description + subpart number in package
for example: C1040805,1 means Capacitor, 100nF, package SMD 0805, first subpart in package

Disclaimer: No warranty at all!
Copyright by Martin Clausen, Germany.
Contact the author: mc AT rotgradpsi DOT de