#include <DigiPotX9Cxxx.h>

const int encoderPinA = 2;
const int encoderPinB = 3;
const int csPin = 4;  // Chip-select pin
const int udPin = 5;  // UpDown (UD) pin

volatile int encoderValue = 0;
volatile int lastEncoded = 0;

void setup() {
  Serial.begin(9600);

  pinMode(encoderPinA, INPUT_PULLUP);
  pinMode(encoderPinB, INPUT_PULLUP);
  pinMode(csPin, OUTPUT);
  pinMode(udPin, OUTPUT);

  digitalWrite(csPin, HIGH); // Deselect MCP4011 initially
  digitalWrite(udPin, LOW);  // Set UD to 0 initially

  attachInterrupt(digitalPinToInterrupt(encoderPinA), handleEncoder, CHANGE);
  attachInterrupt(digitalPinToInterrupt(encoderPinB), handleEncoder, CHANGE);
}

void loop() {
  // Do other tasks here if needed
}

void handleEncoder() {
  int MSB = digitalRead(encoderPinA);
  int LSB = digitalRead(encoderPinB);

  int encoded = (MSB << 1) | LSB;
  int sum = (lastEncoded << 2) | encoded;

  if (sum == 0b1101 || sum == 0b0100 || sum == 0b0010 || sum == 0b1011) {
    // Clockwise rotation
    if (encoderValue < 255) {
      encoderValue++;
      updateMCP4011(encoderValue, true);
    }
  } else if (sum == 0b1110 || sum == 0b0111 || sum == 0b0001 || sum == 0b1000) {
    // Counter-clockwise rotation
    if (encoderValue > 0) {
      encoderValue--;
      updateMCP4011(encoderValue, false);
    }
  }

  lastEncoded = encoded;
}

void updateMCP4011(int value, bool isUp) {
  digitalWrite(csPin, LOW); // Select the MCP4011 chip

  // Set UD to the desired direction
  digitalWrite(udPin, isUp ? HIGH : LOW);
  delayMicroseconds(10);  // Add delay if necessary

  // Toggle UD for the MCP4011 to recognize the change
  digitalWrite(udPin, !digitalRead(udPin));
  delayMicroseconds(10);  // Add delay if necessary

  digitalWrite(csPin, HIGH); // Deselect the MCP4011 chip
  delayMicroseconds(10);  // Add delay if necessary
}