encoder_test

*************************************************************************
//  Name     : mouse_encoder                                              *
//  Author   : Tarilayefa Edward                                          *
//  Notice   : Tari Electronics & Embedded Systems (TEES), 2018.          *
//           : tarielectronics@yahoo.com                                  *
//           : tarielect.edward@gmail.com                                 *
//           : +23408184754883,+23408062251186, Nigeria.                  *
//           : https//:web.facebook.com/groups/teestraining/              *
//           : https//:web.facebook.com/groups/picarduino/                *
//  Date     : 18/07/2018                                                 *
//  Version  : 1.0                                                        *
//  Notes    : A program to read mouse encoder & decode values on lcd &   *
//           : serial monitor.                                            *
//  Reference: xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx         *
//  Compiler : avrgcc                                                     *
//  IDE      : Arduino 1.8.5                                              *
//  Target   : Atmega 328, Arduino Uno, Nano.                             *
//*************************************************************************
//#include <LiquidCrystal.h> //add the lcd library
//LiquidCrystal lcd(7,6,5,4,3,2); //(rs,en,d4,d5,d6,d7)
# include <LiquidCrystal_SR.h> //add 2/3 wire lcd library
LiquidCrystal_SR lcd(8,9); //(data,clock)
//------------------------------------------------------------------------
int EncbtnA = 2; //encoder button switch A
int EncbtnB = 3; //encoder button switch B
int lastState = 0;
int steps = 0; //encoder count steps (0 - 255)
int cw = 0; //encoder direction (-1, 0, 1)
int AState = 0;
int BState = 0;
int State = 0; //state (0, 1, 2, 3)
int clearBtn = 10;
//------------------------------------------------------------------------
//------------------------------------------------------------------------
void setup() //setup function
{
    pinMode(EncbtnA, INPUT_PULLUP);//set pin to input mode
    pinMode(EncbtnB, INPUT_PULLUP);
    pinMode(clearBtn, INPUT_PULLUP);
    //------------------------------------------------------------------------
    lcd.begin(16,20); //initialize 16x2 char lcd
    lcd.clear(); //clear screen
    delay(1000); //wait for 1s
    //------------------------------------------------------------------------
    Serial.begin(9600);
    lcd.print(" Mouse Encoder  ");
    Serial.println("Mouse Encoder");
    delay(3000); //wait for 3s
}
//------------------------------------------------------------------------
//------------------------------------------------------------------------
void loop() //main loop function
{
    int clearState = digitalRead(clearBtn);
    getEncoder();//call encoder decode function
    if(clearState == 0){
        steps = 0;
    }
    //------------------------------------------------------------------------
    Serial.print("Mouse Encoder Steps: ");
    Serial.println(steps);
    //------------------------------------------------------------------------
    lcd.setCursor(0,1);
    lcd.print("Steps: ");
    lcd.print(steps);
    lcd.print("    ");
}
//------------------------------------------------------------------------
//------------------------------------------------------------------------
void getEncoder(){ //encoder decode function
    //read the encoder input pin:
    AState = digitalRead(EncbtnA); //read encoder buttonA
    BState = digitalRead(EncbtnB) << 1; //read encoder buttonB
    State = AState | BState; //read encoder button state
    //------------------------------------------------------------------------
    if (lastState != State){
        switch (State) {
        case 0:  //encoder sequence 0
            if (lastState == 2){
                steps++;
                cw = 1;
            }
            else if(lastState == 1){
                steps--;
                cw = -1;
            }
            break;
            //------------------------------------------------------------------------
        case 1: //encoder sequence 1
            if (lastState == 0){
                steps++;
                cw = 1;
            }
            else if(lastState == 3){
                steps--;
                cw = -1;
            }
            break;
            //------------------------------------------------------------------------
        case 2: //encoder sequence 2
            if (lastState == 3){
                steps++;
                cw = 1;
            }
            else if(lastState == 0){
                steps--;
                cw = -1;
            }
            break;
            //------------------------------------------------------------------------
        case 3: //encoder sequence 3
            if (lastState == 1){
                steps++;
                cw = 1;
            }
            else if(lastState == 2){
                steps--;
                cw = -1;
            }
            break;
            //------------------------------------------------------------------------
        }
    }
    //------------------------------------------------------------------------
    lastState = State; //set encoder state
    //------------------------------------------------------------------------
    delay(1); //wait for 1ms
}
//------------------------------------------------------------------------