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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 REAL THING

Armed with the final schematic, my students went to work wire wrapping the divide by four detector. Photo 1 shows the actual breadboard. Banana connectors are used to get 5 V and ground to the board. After powerup, you must press the zero button to get the LED to light because the machine may come up in states one, two, or three.

Photo 1ýOnes and zeros are entered by pushing the buttons. The green LED goes on whenever the current input pattern evenly divides by four.

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