Arduino Absolute Rotary Encoder Bourns EAW ACE-128

Absolute Rotary Encoder 
EAW0J-B24-AE0128L 

128 positions (clicks) but hard to turn vs KY-040...... 

Arduino code (no i2c ... no library )

The ino file

----------------------------

//https://www.bourns.com/docs/product-datasheets/ace.pdf?sfvrsn=2abe8ff1_3

/*

Bit/Pin correlation: b7 b6 b5 b4 b3 b2 b1 b0 = p8 p7 p6 p5 p4 p3 p2 p1

A binary “1” denotes an “open” switch and a binary “0” denotes a “closed” switch.

Positions 0-127 are seen by a clockwise rotation of the shaft.

 */

 

//On Arduino ground the (left) C pin of the Rotary Encoder

 (between 2 and 3 pin of encoder) 

//your pin arrangement here

const uint8_t rpin1=4;

const uint8_t rpin2=5;

const uint8_t rpin3=6;

const uint8_t rpin4=7;

const uint8_t rpin5=8;

const uint8_t rpin6=9;

const uint8_t rpin7=10;

const uint8_t rpin8=11;

/*use uint8_t and int for return as from 

//hardware/arduino/avr/cores/arduino/wiring_digital.c      

//int digitalRead(uint8_t pin)

*/

int bit0;

int bit1;

int bit2;

int bit3;

int bit4;

int bit5;

int bit6;

int bit7;

//bit7,bit6,bit5,bit4,bit3,bit2,bit1,bit0

int allBitsAsInt;

int rotaryPreviusPosition=-1;

int rotaryCurrentPosition;

//http://www.nongnu.org/avr-libc/user-manual/pgmspace.html

//PROGMEM??

const uint8_t encoderMap_12345678[256] = {

  0xFF,0x38,0x28,0x37,0x18,0xFF,0x27,0x34,0x08,0x39,0xFF,0xFF,0x17,0xFF,0x24,0x0D,

  0x78,0xFF,0x29,0x36,0xFF,0xFF,0xFF,0x35,0x07,0xFF,0xFF,0xFF,0x14,0x13,0x7D,0x12,

  0x68,0x69,0xFF,0xFF,0x19,0x6A,0x26,0xFF,0xFF,0x3A,0xFF,0xFF,0xFF,0xFF,0x25,0x0E,

  0x77,0x76,0xFF,0xFF,0xFF,0x6B,0xFF,0xFF,0x04,0xFF,0x03,0xFF,0x6D,0x6C,0x02,0x01,

  0x58,0xFF,0x59,0xFF,0xFF,0xFF,0xFF,0x33,0x09,0x0A,0x5A,0xFF,0x16,0x0B,0xFF,0x0C,

  0xFF,0xFF,0x2A,0x2B,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x15,0xFF,0x7E,0x7F,

  0x67,0xFF,0x66,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x5B,0xFF,0xFF,0xFF,0xFF,0xFF,

  0x74,0x75,0xFF,0xFF,0x73,0xFF,0xFF,0xFF,0x5D,0x5E,0x5C,0xFF,0x72,0x5F,0x71,0x00,

  0x48,0x47,0xFF,0x44,0x49,0xFF,0xFF,0x1D,0xFF,0x46,0xFF,0x45,0xFF,0xFF,0x23,0x22,

  0x79,0xFF,0x7A,0xFF,0x4A,0xFF,0xFF,0x1E,0x06,0xFF,0x7B,0xFF,0xFF,0xFF,0x7C,0x11,

  0xFF,0xFF,0xFF,0x43,0x1A,0xFF,0x1B,0x1C,0xFF,0x3B,0xFF,0xFF,0xFF,0xFF,0xFF,0x0F,

  0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x05,0xFF,0xFF,0xFF,0x6E,0xFF,0x6F,0x10,

  0x57,0x54,0xFF,0x2D,0x56,0x55,0xFF,0x32,0xFF,0xFF,0xFF,0x2E,0xFF,0xFF,0xFF,0x21,

  0xFF,0x53,0xFF,0x2C,0x4B,0xFF,0xFF,0x1F,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x20,

  0x64,0x3D,0x65,0x42,0xFF,0x3E,0xFF,0x31,0x63,0x3C,0xFF,0x2F,0xFF,0xFF,0xFF,0x30,

  0x4D,0x52,0x4E,0x41,0x4C,0x3F,0xFF,0x40,0x62,0x51,0x4F,0x50,0x61,0x60,0x70,0xFF };

void readRotaryCurrentPosition(){

  bit0=digitalRead(rpin1);

  bit1=digitalRead(rpin2);

  bit2=digitalRead(rpin3);

  bit3=digitalRead(rpin4);

  bit4=digitalRead(rpin5);

  bit5=digitalRead(rpin6);

  bit6=digitalRead(rpin7);

  bit7=digitalRead(rpin8);

  allBitsAsInt = bit7;

  allBitsAsInt <<= 1 ; allBitsAsInt += bit6;

  allBitsAsInt <<= 1 ; allBitsAsInt += bit5;

  allBitsAsInt <<= 1 ; allBitsAsInt += bit4;

  allBitsAsInt <<= 1 ; allBitsAsInt += bit3;

  allBitsAsInt <<= 1 ; allBitsAsInt += bit2;

  allBitsAsInt <<= 1 ; allBitsAsInt += bit1;

  allBitsAsInt <<= 1 ; allBitsAsInt += bit0;

  rotaryCurrentPosition=encoderMap_12345678[allBitsAsInt];  

}

void printForDebug(){// "Endianness" .... little?

    Serial.print("( ");

    Serial.print(bit7);Serial.print(" , ");

    Serial.print(bit6);Serial.print(" , ");

    Serial.print(bit5);Serial.print(" , ");

    Serial.print(bit4);Serial.print(" , ");

    Serial.print(bit3);Serial.print(" , ");

    Serial.print(bit2);Serial.print(" , ");

    Serial.print(bit1);Serial.print(" , ");

    Serial.print(bit0);Serial.print(" ) ");

  

    

    Serial.print("allBitsAsInt= ");

    Serial.print(allBitsAsInt);

    Serial.print(" -> ");

    Serial.print(rotaryCurrentPosition);

    Serial.println();

  

}

void setup() {

  // put your setup code here, to run once:

  Serial.begin(9600);

  pinMode(rpin1,INPUT_PULLUP);

  pinMode(rpin2,INPUT_PULLUP);

  pinMode(rpin3,INPUT_PULLUP);

  pinMode(rpin4,INPUT_PULLUP);

  pinMode(rpin5,INPUT_PULLUP);

  pinMode(rpin6,INPUT_PULLUP);

  pinMode(rpin7,INPUT_PULLUP);

  pinMode(rpin8,INPUT_PULLUP);

  // really need this ?

  rotaryPreviusPosition=-1;

  readRotaryCurrentPosition();

}

void loop() {

  readRotaryCurrentPosition();

  if(rotaryPreviusPosition!=rotaryCurrentPosition){

    rotaryPreviusPosition=rotaryCurrentPosition;

    //printForDebug();

    Serial.println(rotaryCurrentPosition);

  }

  else{

    //Serial.println("user didnt turn the encoder");

  }

  delay(10);

}//end loop