ZIP GSX mods (more)

[wbaguhn@nyx10.cs.du.edu (Will Baguhn)]

Ok, the latest modification is pretty straightforward.  I decided I wanted
a Cache HIT light instead of a Cache MISS light.  Went to Rat Shack, bought a
pack of Green LEDs (I like green.  Blue or Orange will work just as well.  ;) 

I tried adding an inverter to the circuit but it just didn't want to play
(obviously a cache HIT is the opposite of a cache MISS, and the LED on the
board lights up for cache MISSes).  Through the experimenting, I found
that I could get the LED to light as desired without any "extra" hardware
except the LED itself.

Simple mod:  solder in the Anode of the LED to the Anode of the Cache Miss.
Solder the Cathode to the Cathode of the Power LED.

(even easier way to say it: there are four solder points for the existing
LEDs.  We use the two in the middle.  The long lead goes to the yellow side,
the short to the red.  position as is comfortable.  I can only guess that this
would be a nice thing to attach to the TURBO light on the front of a tower
case, should anyone ever mount a IIgs/ZipGSX inside a tower case...
(also, it might be nice to turn SW1-6 OFF and connect the pins to the TURBO
button on front.  I don't know how useful it would be, but it might come in
handy one of these days...)
-- 
                                      --- Rev. SPQR (wbaguhn@nyx.net)