I had a new hardware only idea, this will guarantee no logic races, though
under a rather odd circumstance it coudl be "unfair"

use a counter with at least 8 discrete outputs and a 555 oscilator set to
some conveninent frequency - say 20 Khz. the counter will now energize one
of 8 outputs one at a time in rapid succession.

each counter output goes to a switch. Each counter output also drives an
LED through a resistor. All LEDs will glow dimly.

Other end of all switches goes to a latch (two NAND gates will do the
trick). when you press a switch (any switch) the latch sets.

Output of latch goes to 555 "enable" line dragging it to the "disable"
condition - oscillator stops, counter stops - the LED on the line that was
active when the switch is pressed will glow brightly, all others off.

chip count is four, if I counted right, power draw is minimal, particularly
with CMOS.


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