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PATTERNS IN NUMBERS

A State Machine Design for Binary Pattern Recognition

by James Antonakos

Start ý The Problem ý Enumeration ý State Diagram Approach ý A Little Synchronous Logic ý State Transition Table ý Let Karnaugh Maps Find the Patterns ý A Hotshot One-Shot ý The Real Thing ý Other Implementations ý I Challenge Youý ý Sources and PDF

THE PROBLEM

When teaching digital electronics, I try to present an interesting topic that can be investigated through the use of some digital hardware. This past semester, I asked my class to solve the following problem: design a digital circuit that will turn on an LED whenever its serial binary input pattern represents a number that is evenly divisible by four (100). The number is presented MSB-first.

You may be thinking of using shift registers to solve the problem, but letýs take a look at several different approaches. Bear in mind that youýll end up using many typical digital techniques as you progress through the solution.

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