http://www.nightmarepark.com/public/hou ... CPU002.jpg
shows it piggybacked. It is based on Darren's SBC-1 but has no jumpers for i/o chip select; I use 65c22 exclusively in there.

Basic order, 4 MHz crystal oscillator on top
27256
65256 ram
65c02
65c22

and the ttls on the left are:
74ls04
74ls00
74ls30

The red LED shows the +5 volt line and the green LED is tied to A7 as a self test showoff by flashing.

bottom tiny board, interface. Left board is the sound board. Board in back is the original pinball. LEDS on the interface board show all pinball voltages, for convenience.

Eventually, all 3 boards will be redone into a single board.

Having fun with it all

_________________
"My biggest dream in life? Building black plywood Habitrails"