Arduino code to read the angle register from the MassMind.org ENC1 via 3 wire read only mode.

MassMind.org ENC1 3Wire ReadAngle Arduino

/*
Source from
http://forum.arduino.cc/index.php?topic=78881.msg1375885#msg1375885
 * Ahmad Byagowi (ahmadexp@gmail.com)
 * Date : Aug 31, 2013
 * All code (c)2013 Ahmad Byagowi Consultant. all rights reserved
20170508 Minor edits to improve clarity by James Newton.
*/

//c2 pin tied to ground for 3 wire mode
int cs  = A3;
int dio = A5; //pull down resistor (10K-100K) required
int clk = A4;

void init_as5134(void){
  digitalWrite(cs, LOW);
  digitalWrite(clk, LOW);
  pinMode(cs,  OUTPUT);
  pinMode(clk, OUTPUT);
  pinMode(dio, INPUT);
  }

int read_as5134(void){
  int clock_p;
  unsigned int data=0;
  digitalWrite(cs,LOW);
  digitalWrite(clk,LOW);
  digitalWrite(cs,HIGH);
  delay(1);
  for(clock_p=21;clock_p--;clock_p>0){
    digitalWrite(clk,LOW);
    delay(1);
    digitalWrite(clk,HIGH);
    delay(1);
    if(clock_p<9){
      if(digitalRead(dio)) {
        data+=(1<<(clock_p));
		}
      }
    }
  digitalWrite(clk,LOW);
  digitalWrite(cs,LOW);
  return data;
  }

// the setup routine runs once when you press reset:
void setup() {
  init_as5134();
  Serial.begin(115200);
  }
// the loop routine runs over and over again forever:
void loop() {
  Serial.println(read_as5134());
  delay(10);
  }