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SiriusHardware · 2nd Aug 2021, 10:27 pm

You could map 0-9 A-F as they are on the standard keypad and map all the other alpha characters etc into the currently unused row / column positions and sort it all out using a lookup table embedded in whatever RAM based application will be reading the full keyboard. Assuming outboard RAM mapped at 0200-07FF, of which 512 bytes is dedicated as screen RAM, the system will have 1K + 640 bytes of RAM for your word processor / terminal program to run in. Slightly more than a basic ZX81.

2nd Aug 2021, 10:27 pm	#71
SiriusHardware Dekatron Join Date: Aug 2011 Location: Newcastle, Tyne and Wear, UK. Posts: 11,581	Re: MK14 Programming Interface You could map 0-9 A-F as they are on the standard keypad and map all the other alpha characters etc into the currently unused row / column positions and sort it all out using a lookup table embedded in whatever RAM based application will be reading the full keyboard. Assuming outboard RAM mapped at 0200-07FF, of which 512 bytes is dedicated as screen RAM, the system will have 1K + 640 bytes of RAM for your word processor / terminal program to run in. Slightly more than a basic ZX81.