# I found a free “Logic Minimizing” tool called “Logic Friday”. You can enter gates OR Truth Tables OR Equations and it uses a heuristic (best guess) to minimize redundant circuits. NOR gates have fascinated me for years because of how their truth tables work, especially when layered. My first experiment is with 4 4-input NOR gates that narrow down through 1 4-input NOR gate to produce 1 function (output). What’s it gonna do? No idea.

I found a free “Logic Minimizing” tool called “Logic Friday”.

You can enter gates OR Truth Tables OR Equations and it uses a heuristic (best guess) to minimize redundant circuits.

NOR gates have fascinated me for years because of how their truth tables work, especially when layered.

My first experiment is with 4 4-input NOR gates that narrow down through 1 4-input NOR gate to produce 1 function (output).

What’s it gonna do? No idea.
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It showed me that I made an equation that’s 2 million characters long.The Truth Table I made is 65.537 rows in 16 colums with 1 additional output column.
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50625 TRUE
14911 FALSE
0 “don’t care”
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Oh cool. It shrunk the Truth Table from 65537 rows down to 256 rows, with a LOT of “don’t cares”.
====== I can do the same with :
IC Qty
Dual 4-Input AND 1
Dual 4-Input OR 2
TOTAL PACKAGES 3
but why.. hmmm?

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Ok. I can see it by tracing.. As long as you pick AT LEAST ONE of each of the four, you have a “good circuit”. You can pick more than one out of each, but AT LEAST one.
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it is. That blew me away a bit. I’ve been meaning to dive into this for a long time and in just a few minutes, I like i
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• 4-nor (7.38 KB
24.03.2019
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