Introduction PS/2 Keyboard interface for the Amiga 500.
The Amiga 500 is also slowly but surely starting to suffer from keyboard problems.
Many keyboards for the Amiga are made by Mitsumi and work on the basis of a flexible foil with a matrix of wafer-thin tracks.
Those tracks weather, break, get dirty and you can name 1000 reasons why the keyboard does not function properly or even no longer functions at all.
There are roughly 3 types of keyboards for the Amiga 500 series :
Hitek, Samsung and Mitsumi , and that order is from good to less good.
If you now want to build your 500 eg in a different housing or if you no longer have a working keyboard, there is now a simple and cheap solution to connect a PS/2 keyboard to your Amiga 500 / 500+.
It is an interface adapter that you plug into the internal keyboard connector and that has a PS/2 plug.
Furthermore, the interface has a configurable Clock / Data poling, as there are 2 different pinouts used by Commodore for the Amiga 500 product line (sigh).
By moving 2 jumpers you can use this adapter in all types of Amiga 500 / 500+.
Because the PC keyboards do not have a compatible Power LED and Floppydisk activity LED in the keyboard, these have been made available on the adapter.
Reset functionality is also available on the PS/2 keyboard, use the keys <CTRL> - <Left Windows Key> - <Right Windows Key>
The amiga will reset as if you pressed CTRL-Amiga-Amiga.
Note: this is not just an adapter plug or cable, there is more to it than just that.
The heart of this interface is a PIC microcontroller, this PIC takes care of the protocol conversion.
it receives the data packets from the PS/2 keyboard, interprets the data, then converts it to a scan code recognizable to the Amiga, and then forwards it to the Amiga.
Because you can program the PIC, you can also capture the extra keys (Multimedia, F11, F12, Ins, Del, etc.) from your PS/2 keyboard.
(Only then you have to run a piece of software on the Amiga side (MMKEYBOARD), because the Amiga itself does not know these extra keys.)