Patterns in Numbers

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PATTERNS IN NUMBERS

Technically Speaking A State Machine Design for Binary Pattern Recognition

by James Antonakos

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

OTHER IMPLEMENTATIONS

State machines also can be implemented in software using a few lines of C code. You can see this in Listing 1, where states is a two-dimensional array containing the state transition values.

next = 0;
input = inputStream[0];
currentState = 0;
do
{
nextState = states[currentState][input];
.
.
.
currentState = nextState;
input = inputStream[next++];
} while(next < strlen(inputStream));
.

Listing 1ıHere you can see a C code sample used to simulate state machine operation.

Even a combination of hardware and software could be used, such as the BASIC Stamp. A short BASIC program could sample two digital inputs and control an output bit to indicate an even division.

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