This sketch is used by Exercise: Input Pattern Matching.
The full code is all in one file InputMatcher1.ino.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 | // InputMatcher1.ino : Arduino program to demonstrate a simple finite state machine program structure.
// Copyright (c) 2014, Garth Zeglin. All rights reserved. Licensed under the terms
// of the BSD 3-clause license as included in LICENSE.
// The baud rate is the number of bits per second transmitted over the serial port.
const long BAUD_RATE = 115200;
// The state machine uses a single switch input.
const int INPUT_PIN = 4;
/****************************************************************/
/**** Standard entry points for Arduino system ******************/
/****************************************************************/
// Standard Arduino initialization function to configure the system.
void setup()
{
// initialize the Serial port
Serial.begin( BAUD_RATE );
// configure our trivial inputs
pinMode( INPUT_PIN, INPUT );
pinMode( LED_BUILTIN, OUTPUT );
}
/****************************************************************/
// Standard Arduino polling function.
// This demonstrates the simplest method for representing a finite state machine
// as an Arduino program: the program counter is used to represent the current
// state as the current execution position with the program. Note that a
// highly-connected state graph is not necessarily well represented by a
// hierarchical code structure, hence the use of goto, which is generally
// frowned upon in structured programming.
void loop()
{
int input;
start:
Serial.println("Entering start state.");
digitalWrite(LED_BUILTIN, LOW);
delay(1000);
Serial.println("Sampling input.");
input = digitalRead( INPUT_PIN );
if (input) goto state1;
else goto start;
state1:
Serial.println("Entering state 1.");
digitalWrite(LED_BUILTIN, LOW);
delay(1000);
Serial.println("Sampling input.");
input = digitalRead( INPUT_PIN );
if (input) goto start;
else goto state2;
state2:
Serial.println("Entering state 2.");
digitalWrite(LED_BUILTIN, LOW);
delay(1000);
Serial.println("Sampling input.");
input = digitalRead( INPUT_PIN );
if (input) goto state3;
else goto state1;
state3:
Serial.println("Entering state 3.");
digitalWrite(LED_BUILTIN, HIGH);
delay(1000);
Serial.println("Sampling input.");
input = digitalRead( INPUT_PIN );
if (input) goto state3;
else goto start;
}
/****************************************************************/
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