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Switching roms - without (extra) switch

Hi -

I have been thinking about a (invisibly) way to switch between different kernals, without having to install extra switches. ( Im using a 27c512, as described on http://www.rift.dk/blog/upgrading-and-consolidating-commodore-128-roms )

An easy way, would be to connect it to the cap-lock or 40/80-lock... but that is stupid, as you can no longer use caps-lock or change 40/80 freely. - And anyway, this limits us to 2 modes. More modes could be used to enable/select a extra ROMs, like "The Servent" or Basic-8.

So, why not add a small 8-pin microcontroler ( like PIC12c675 ), to remember the last setting. - Kind of a VERY slow ( static ) memory controler :-) ?
One output could be used to control the power led, to show the current mode ( by some fancy blinking at power up.)

Input could be the cap-lock and 40/80 switches, but that still gets weird very fast... Yes it could just record how the state of the switches at power-on.
But then you would need to cycle power, to change it ( not just reset ).
So perhaps no easy, magic solutions? :-)

Any ( out of the box ) ideas or advice would be appreciated.

/holger

Edited by: holger on 2015-02-17 13:13