// 旋轉編碼器　Rotary Encoder
// 用旋轉編碼器的旋轉方向和旋轉量，來操控一個十段 LED排燈
// https://sites.google.com/view/rayarduino/rotary-encoder
/*
#define CLK 2      //旋轉編碼器 CLK 連接 Arduino pin 2
#define DT  3      //旋轉編碼器 DT 連接 Arduino pin 3
#define SW  4      //旋轉編碼器 SW 連接 Arduino pin 4

#define LED1 5     //十段 LED 排燈連接 Arduino pins 5-13 及 A0
#define LED2 6
#define LED3 7
#define LED4 8
#define LED5 9
#define LED6 10  
#define LED7 11   
#define LED8 12   
#define LED9 13   
#define LED10 A0   

int pin=2;           //定義一些整數；
int count = 0;
int lastCLK = 0;     //lastCLK 為旋轉編碼器 CLK 預設狀態 =0

 
void setup()
{
  pinMode(SW, INPUT);      //Arduino 預備讀入旋轉編碼器 CLK, DT, and SW 狀態 
  digitalWrite(SW, HIGH);  //旋轉編碼器按鍵 SW為上拉電阻模式
  pinMode(CLK, INPUT);
  pinMode(DT, INPUT);
  
  //設置系統岔斷模式，當pin 2 輸入狀態有改變( CHANGE ) 時，呼叫副程式 ClockChanged() 
  attachInterrupt(digitalPinToInterrupt(pin), ClockChanged, CHANGE);  
  
  pinMode(LED1, OUTPUT);  //Arduino 對外輸出電壓控制 十段 LED 排燈
  pinMode(LED2, OUTPUT);
  pinMode(LED3, OUTPUT);
  pinMode(LED4, OUTPUT);
  pinMode(LED5, OUTPUT);
  pinMode(LED6, OUTPUT);
  pinMode(LED7, OUTPUT);
  pinMode(LED8, OUTPUT);
  pinMode(LED9, OUTPUT);
  pinMode(LED10, OUTPUT);
  
  Serial.begin(9600);
}

//本程式 void loop() 唯一做的事，是當旋轉編碼器按鍵 SW 被按下時，系統重設，整數 count 歸零，熄滅所有LED燈。
void loop()
{
  if (!digitalRead(SW) && count != 0) 
  {
    count = 0;
    Serial.print("count:");
    Serial.println(count);
    digitalWrite(LED1, LOW);
    digitalWrite(LED2, LOW);
    digitalWrite(LED3, LOW);
    digitalWrite(LED4, LOW);
    digitalWrite(LED5, LOW);
    digitalWrite(LED6, LOW);
    digitalWrite(LED7, LOW);
    digitalWrite(LED8, LOW);
    digitalWrite(LED9, LOW);
    digitalWrite(LED10, LOW);

  }
}

void LedOutput(int value)   //副程式 void LedOutput 。當輸入值 value 為 1 時，點亮一個LED燈；value 為 2 時，點亮兩個LED燈。依此類推。
{
  digitalWrite(LED1, LOW);  //先把所有LED關掉
  digitalWrite(LED2, LOW);
  digitalWrite(LED3, LOW);
  digitalWrite(LED4, LOW);
  digitalWrite(LED5, LOW);
  digitalWrite(LED6, LOW);
  digitalWrite(LED7, LOW);
  digitalWrite(LED8, LOW);
  digitalWrite(LED9, LOW);
  digitalWrite(LED10, LOW);

  if (value >= 1 && value <= 10) {
    switch(value) {
      case 1: 
        digitalWrite(LED1, HIGH);
        break;
      case 2:
        digitalWrite(LED1, HIGH);
        digitalWrite(LED2, HIGH);
        break;
      case 3:
        digitalWrite(LED1, HIGH);
        digitalWrite(LED2, HIGH);
        digitalWrite(LED3, HIGH);
        break;
      case 4:
        digitalWrite(LED1, HIGH);
        digitalWrite(LED2, HIGH);
        digitalWrite(LED3, HIGH);
        digitalWrite(LED4, HIGH);
        break;
     case 5:
        digitalWrite(LED1, HIGH);
        digitalWrite(LED2, HIGH);
        digitalWrite(LED3, HIGH);
        digitalWrite(LED4, HIGH);
        digitalWrite(LED5, HIGH);
        break;
      case 6:
        digitalWrite(LED1, HIGH);
        digitalWrite(LED2, HIGH);
        digitalWrite(LED3, HIGH);
        digitalWrite(LED4, HIGH);
        digitalWrite(LED5, HIGH);
        digitalWrite(LED6, HIGH);
        break;
      case 7:
        digitalWrite(LED1, HIGH);
        digitalWrite(LED2, HIGH);
        digitalWrite(LED3, HIGH);
        digitalWrite(LED4, HIGH);
        digitalWrite(LED5, HIGH);
        digitalWrite(LED6, HIGH);
        digitalWrite(LED7, HIGH);
        break;
      case 8:
        digitalWrite(LED1, HIGH);
        digitalWrite(LED2, HIGH);
        digitalWrite(LED3, HIGH);
        digitalWrite(LED4, HIGH);
        digitalWrite(LED5, HIGH);
        digitalWrite(LED6, HIGH);
        digitalWrite(LED7, HIGH);
        digitalWrite(LED8, HIGH);
        break;
      case 9:
        digitalWrite(LED1, HIGH);
        digitalWrite(LED2, HIGH);
        digitalWrite(LED3, HIGH);
        digitalWrite(LED4, HIGH);
        digitalWrite(LED5, HIGH);
        digitalWrite(LED6, HIGH);
        digitalWrite(LED7, HIGH);
        digitalWrite(LED8, HIGH);
        digitalWrite(LED9, HIGH);      
        break;   
      case 10:
        digitalWrite(LED1, HIGH);
        digitalWrite(LED2, HIGH);
        digitalWrite(LED3, HIGH);
        digitalWrite(LED4, HIGH);
        digitalWrite(LED5, HIGH);
        digitalWrite(LED6, HIGH);
        digitalWrite(LED7, HIGH);
        digitalWrite(LED8, HIGH);
        digitalWrite(LED9, HIGH);     
        digitalWrite(LED10,HIGH);        
        break;           
    }
  }
}

void ClockChanged()   //副程式 void ClockChanged () 
{   
  int clkValue = digitalRead(CLK);  // Arduino 讀入旋轉編碼器 CLK 狀態
  int dtValue = digitalRead(DT);    // Arduino 讀入旋轉編碼器 DT 狀態
  if (lastCLK != clkValue)
  {
    lastCLK = clkValue;
    count += (clkValue != dtValue ? 1 : -1);  //旋轉編碼器順時針旋轉時，count +1；逆時針旋轉時， count -1

    Serial.print("count:");
    Serial.println(count);
    int rcount = count/2;  //旋轉編碼器轉一格，count 會被+2 ，LED 一次亮兩個； 為使旋轉編碼器轉一格， LED亮一個，故把 count÷2
    LedOutput(rcount);     //把 count ÷2 後的值 (rcount) 傳至副程式 LedOutput (value)
  }
}
*/

// How Rotary Encoder Works and Interface It with Arduino
// https://lastminuteengineers.com/rotary-encoder-arduino-tutorial/#google_vignette

// Rotary Encoder Inputs
#define CLK 2
#define DT 3
#define SW 4

int counter = 0;
int currentStateCLK;
int lastStateCLK;
String currentDir ="";
unsigned long lastButtonPress = 0;

void setup() {
        
	// Set encoder pins as inputs
	pinMode(CLK,INPUT);
	pinMode(DT,INPUT);
	pinMode(SW, INPUT_PULLUP);

	// Setup Serial Monitor
	Serial.begin(9600);

	// Read the initial state of CLK
	lastStateCLK = digitalRead(CLK);
}

void loop() {
        
	// Read the current state of CLK
	currentStateCLK = digitalRead(CLK);

	// If last and current state of CLK are different, then pulse occurred
	// React to only 1 state change to avoid double count
	if (currentStateCLK != lastStateCLK  && currentStateCLK == 1){

		// If the DT state is different than the CLK state then
		// the encoder is rotating CCW so decrement
		if (digitalRead(DT) != currentStateCLK) {
			counter --;
			currentDir ="CCW";
		} else {
			// Encoder is rotating CW so increment
			counter ++;
			currentDir ="CW";
		}

		Serial.print("Direction: ");
		Serial.print(currentDir);
		Serial.print(" | Counter: ");
		Serial.println(counter);
	}

	// Remember last CLK state
	lastStateCLK = currentStateCLK;

	// Read the button state
	int btnState = digitalRead(SW);

	//If we detect LOW signal, button is pressed
	if (btnState == LOW) {
		//if 50ms have passed since last LOW pulse, it means that the
		//button has been pressed, released and pressed again
		if (millis() - lastButtonPress > 50) {
			Serial.println("Button pressed!");
		}

		// Remember last button press event
		lastButtonPress = millis();
	}

	// Put in a slight delay to help debounce the reading
	delay(1);
}

/*
// Rotary Encoder Inputs
#define CLK 2
#define DT 3

int counter = 0;
int currentStateCLK;
int lastStateCLK;
String currentDir ="";

void setup() {

	// Set encoder pins as inputs
	pinMode(CLK,INPUT);
	pinMode(DT,INPUT);

	// Setup Serial Monitor
	Serial.begin(9600);

	// Read the initial state of CLK
	lastStateCLK = digitalRead(CLK);
	
	// Call updateEncoder() when any high/low changed seen
	// on interrupt 0 (pin 2), or interrupt 1 (pin 3)
	attachInterrupt(0, updateEncoder, CHANGE);
	attachInterrupt(1, updateEncoder, CHANGE);
}

void loop() {
    //Do some useful stuff here
}

void updateEncoder(){
	// Read the current state of CLK
	currentStateCLK = digitalRead(CLK);

	// If last and current state of CLK are different, then pulse occurred
	// React to only 1 state change to avoid double count
	if (currentStateCLK != lastStateCLK  && currentStateCLK == 1){

		// If the DT state is different than the CLK state then
		// the encoder is rotating CCW so decrement
		if (digitalRead(DT) != currentStateCLK) {
			counter --;
			currentDir ="CCW";
		} else {
			// Encoder is rotating CW so increment
			counter ++;
			currentDir ="CW";
		}

		Serial.print("Direction: ");
		Serial.print(currentDir);
		Serial.print(" | Counter: ");
		Serial.println(counter);
	}

	// Remember last CLK state
	lastStateCLK = currentStateCLK;
}
*/

/*
// Include the Servo Library
#include <Servo.h>

// Rotary Encoder Inputs
#define CLK 2
#define DT 3

Servo servo;
int counter = 0;
int currentStateCLK;
int lastStateCLK;

void setup() {

	// Set encoder pins as inputs
	pinMode(CLK,INPUT);
	pinMode(DT,INPUT);
	
	// Setup Serial Monitor
	Serial.begin(9600);
	
	// Attach servo on pin 9 to the servo object
	servo.attach(9);
	servo.write(counter);
	
	// Read the initial state of CLK
	lastStateCLK = digitalRead(CLK);
}

void loop() {
        
	// Read the current state of CLK
	currentStateCLK = digitalRead(CLK);
	
	// If last and current state of CLK are different, then pulse occurred
	// React to only 1 state change to avoid double count
	if (currentStateCLK != lastStateCLK  && currentStateCLK == 1){
		
		// If the DT state is different than the CLK state then
		// the encoder is rotating CCW so decrement
		if (digitalRead(DT) != currentStateCLK) {
			counter --;
			if (counter<0)
				counter=0;
		} else {
			// Encoder is rotating CW so increment
			counter ++;
			if (counter>179)
				counter=179;
		}
		// Move the servo
		servo.write(counter);
		Serial.print("Position: ");
		Serial.println(counter);
	}
	
	// Remember last CLK state
	lastStateCLK = currentStateCLK;
}
*/