state machine example A

/*
 *  This is a sample sketch to show a solution to Simons 4x LED challenge
 *  see: https://www.facebook.com/groups/1437500423193520/permalink/1705520479724845/
 *
 *  The challenge is that any one of three events can occur
 *    Event A : the user can press a button
 *    Event B : time has passed
 *    Event C : the user releases the button
 *
 *    Event A & C can only happen sequentally. That is one event has to happen before the other can happen
 *    Ecent B can only happen after event A
 *    Event C can happen at any time after event A has happened
 *
 *
 * Test circuit:
 *
 *  Connect a push-button to pin 10 (ButtonPin), connect other side of button to ground.
 *  Connect LEDs (including resistors) to pins 3, 4, 5 & 6
 *
 *  Pin 13 (StatusPin) is used as a I-am-alive-blinking-signal
 *
 *  This skect uses the ButtoOne library from https://github.com/MrAlvin/ButtonOne
 *
 */

#include "ButtonOne.h"

// Setup a ButtonOne instance on pin 10.
ButtonOne button(10);

#define LED1_PIN 3
#define LED2_PIN 4
#define LED3_PIN 5
#define LED4_PIN 6
#define DEBUG_LED_PIN 13

boolean button_pressed = false;    // flag used to evaluate on event B - the passing of time between activation of LEDs
unsigned long previousMillis = 0;  // used to track the passing of "interval" time
unsigned long interval = 0;        // used to track time to occur between LED activations. Default action is; that LED 1 turns on, as the button is pressed
int idx = 1;                       // used keep track of the current state in the state-machine

//*********************************************
// setup function - to run once:
//*********************************************
void setup() {
  // enable the standard led on pin 13.
  pinMode(DEBUG_LED_PIN, OUTPUT);      // sets the digital pin as output

  pinMode(LED1_PIN, OUTPUT);      // sets the digital pin as output
  pinMode(LED2_PIN, OUTPUT);      // sets the digital pin as output
  pinMode(LED3_PIN, OUTPUT);      // sets the digital pin as output
  pinMode(LED4_PIN, OUTPUT);      // sets the digital pin as output

  //initiate internal button management values
  button.begin();

  // link the Press function to be called on a button Press event.
  button.attachPress(btnPress);
  // link the Release function to be called on a button Release event.
  button.attachRelease(btnRelease);
} // setup


//*********************************************
// main code -  to run repeatedly:
//*********************************************
void loop() {
  // check for event A (button press)
  button.check();

  // if event A has occured, check for event B
  if(button_pressed)  is_it_time();

  // something I usually use when dealing with event-style programming
  debug_blink();  // lets me know that the program is up and running
} // loop


//*********************************************
// button events:
//*********************************************
// this function will be called when the button is pressed
void btnPress() {
  button_pressed = true;  // raise flag. Response to flag happens in the main loop()
} // btnPress

// this function will be called when the button is released - which is also event C
void btnRelease() {
  button_pressed = false; // button is no longer pressed
  LedsOff();              // turn off all LEDs
  idx = 1;                // reset the pointer in the state machine, so ready for next press of the button
  previousMillis = 0;     // reset the time tracker
  interval = 0;           // set time interval for time to pass between pressing of button to turn on LED 1
} // btnRelease


//*********************************************
// timer function:
//*********************************************
void is_it_time() {

  if (millis() - previousMillis > interval) {
    previousMillis = millis();  // store the current time, so we can waite "interval" amount of time, before we take next action

    // do you timed event
    timed_action();
  }
} //is_it_time


//*********************************************
// state machine:
//*********************************************
void timed_action() {
  switch(idx){
    case 1: //turn on one led
      led_1_on();
      interval = 1000; // time until LED 2 will be turned on
      idx++;           // ready to activate LED 2
      break;
    case 2: //turn on two leds
      led_2_on();
      interval = 1000; // time until LED 3 will be turned on
      idx++;           // ready to activate LED 3
      break;
    case 3: //turn on three leds
      led_3_on();
      interval = 1000; // time until LED 4 will be turned on
      idx++;           // ready to activate LED 4
      break;
    case 4: //turn on four leds
      led_4_on();
      idx++;           // ready to simply waite
      break;
    case 5: //no changes
      break;
  }
} //timed_action

//*********************************************
// LED functions:
//*********************************************
void LedsOff(){
  led_1_off();
  led_2_off();
  led_3_off();
  led_4_off();
}


void led_1_on(){
  digitalWrite(LED1_PIN, HIGH);
}

void led_1_off(){
  digitalWrite(LED1_PIN, LOW);
}


void led_2_on(){
  digitalWrite(LED1_PIN, HIGH);
}

void led_2_off(){
  digitalWrite(LED1_PIN, LOW);
}


void led_3_on(){
  digitalWrite(LED1_PIN, HIGH);
}

void led_3_off(){
  digitalWrite(LED1_PIN, LOW);
}

void led_4_on(){
  digitalWrite(LED1_PIN, HIGH);
}

void led_4_off(){
  digitalWrite(LED1_PIN, LOW);
}


//*********************************************
// I-am-alive debug LED blink function:
//*********************************************
#define ON_DELAY  500
#define OFF_DELAY 500

void debug_blink() {
  static unsigned long blink_millis = 0;
  static unsigned long blink_interval = 0;
  static boolean do_on = true;

  if ( millis() - blink_millis >  blink_interval )  { // if its time to change the blink
    if (do_on) { //use a flag to determine wether to turn on or off the Blink LED
      digitalWrite(DEBUG_LED_PIN, HIGH);   // set the LED on, if okay to use power for it
      blink_millis = millis();
      blink_interval = ON_DELAY; // wait for a second
      do_on = false;
    }else{
      digitalWrite(DEBUG_LED_PIN, LOW);    // set the LED off
      // set the time to do next blink
      blink_millis = millis();
      blink_interval = OFF_DELAY;  // wait for a second
      do_on = true;
    }
  }
} //debug_blink

// End