prindle@nadc (05/21/86)
From: prindle@NADC I have one of these too, but it uses a novel approach. It's a micro-switch hall effect keyboard, with a homebrew row-column encoder and discrete shift/ ctrl logic, and plugs into the two *joystick* ports. The major disadvantage is it requires a keyboard scan routine be resident somewhere in memory and be wedged into the interrupt processing (this has not proven to be much of a disadvantage with the software with which I use it). The major advantages are complete key definition control; parallel operation with normal keyboard; no opening the case; and incredibly smooth key action. No, it doesn't take it's power from the 64 (ZaP, pOw, MeLt!). Another disadvantage is that most of the hall-effect switches on this kbd generate only pulses, not levels, so it is not possible to detect a key being held down. Frank Prindle Prindle@NADC.arpa