//To modify your Arduino code so that it requires three encoder pulses to change the selection, you will need to keep track of the pulse count and only update the output selection after three pulses have been detected. Here's how you can achieve that:

//### Modified Code

#include <Wire.h> 
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <Encoder.h>

// OLED display settings
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET    -1
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

// Rotary encoder pins
#define ENCODER_PIN_A 2
#define ENCODER_PIN_B 3
#define ENCODER_SWITCH 4
Encoder myEnc(ENCODER_PIN_A, ENCODER_PIN_B);

// Output pins
#define OUTPUT1 5
#define OUTPUT2 6
#define OUTPUT3 7

// MPG status input pin
#define MPG_STATUS_PIN 8

// Variables
int currentOutput = 0;
int lastOutput = 0;
long oldPosition = -999;
unsigned long lastSwitchPressTime = 0;
bool switchPressed = false;
bool lastMpgStatus = HIGH;
unsigned long lastDisplayUpdateTime = 0;
const unsigned long DISPLAY_UPDATE_INTERVAL = 100; // Update display every 100 ms

// Pulse counting
int pulseCount = 0; // Counter for pulses

void setup() {
  // Initialize serial communication
  Serial.begin(9600);

  // Initialize OLED display
  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    for (;;);
  }
  display.display();
  delay(2000);
  display.clearDisplay();

  // Set output pins
  pinMode(OUTPUT1, OUTPUT);
  pinMode(OUTPUT2, OUTPUT);
  pinMode(OUTPUT3, OUTPUT);

  // Set encoder switch pin
  pinMode(ENCODER_SWITCH, INPUT_PULLUP);

  // Set MPG status pin
  pinMode(MPG_STATUS_PIN, INPUT_PULLUP);

  // Set initial state of output pins
  digitalWrite(OUTPUT1, HIGH);
  digitalWrite(OUTPUT2, HIGH);
  digitalWrite(OUTPUT3, HIGH);
  digitalWrite(OUTPUT1, LOW);
  delay(300);
  digitalWrite(OUTPUT1, HIGH);

  // Display initial output
  displayOutput(currentOutput);
}

void loop() {
  long newPosition = myEnc.read() / 4;

  // Update position and pulse counting
  if (newPosition != oldPosition) {
    oldPosition = newPosition;
    // Increment or decrement pulse count based on direction
    pulseCount += (newPosition > oldPosition) ? 1 : -1;

    // Change selection only after 3 pulses
    if (abs(pulseCount) >= 3) {
      currentOutput = (currentOutput + (pulseCount > 0 ? 1 : -1)) % 3; // Ensure non-negative output
      if (currentOutput < 0) {
        currentOutput += 3; // Wrap around
      }
      displaySelectedOutput(currentOutput);
      lastSwitchPressTime = millis();
      switchPressed = false;
      pulseCount = 0; // Reset pulse count after changing selection
    }
  }

  // Handle encoder switch state
  bool encoderSwitchState = digitalRead(ENCODER_SWITCH) == LOW;
  if (encoderSwitchState != switchPressed) {
    if (encoderSwitchState) {
      lastOutput = currentOutput;
      setOutputLow(currentOutput);
      displayOutput(currentOutput);
    }
    switchPressed = encoderSwitchState;
  } else if (switchPressed && (millis() - lastSwitchPressTime > 1000)) {
    displayOutput(lastOutput);
    switchPressed = false;
  }

  // Check MPG status pin state and update display based on frequency
  unsigned long currentTime = millis();
  if (currentTime - lastDisplayUpdateTime >= DISPLAY_UPDATE_INTERVAL) {
    bool currentMpgStatus = digitalRead(MPG_STATUS_PIN);
    if (currentMpgStatus != lastMpgStatus) {
      lastMpgStatus = currentMpgStatus;
      displayOutput(currentOutput);  // Refresh display to update MPG status
    }
    lastDisplayUpdateTime = currentTime;
  }
}

void setOutputLow(int output) {
  // Turn selected output pin LOW and then HIGH with a short delay
  digitalWrite(OUTPUT1 + output, LOW);
  delay(300);
  digitalWrite(OUTPUT1 + output, HIGH);
}

void displayOutput(int output) {
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0, 0);
  display.println(digitalRead(MPG_STATUS_PIN) == LOW ? "JOG Enabled" : "*Disabled");
  display.setTextSize(2);
  display.setCursor(0, 16);
  display.println(outputToString(output));
  display.display();
}

void displaySelectedOutput(int output) {
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0, 0);
  display.println(digitalRead(MPG_STATUS_PIN) == LOW ? "JOG Enabled" : "*Disabled");
  display.setTextSize(2);
  display.setCursor(0, 16);
  display.println("Select");
  display.setCursor(0, 32);
  display.println(outputToString(output));
  display.display();
}

String outputToString(int output) {
  switch (output) {
    case 0: return "x 1";
    case 1: return "x 10";
    case 2: return "x 100";
    default: return "Unknown";
  }
}

//### Key Changes:
//1. **Pulse Counting**: Added a `pulseCount` variable to count the number of encoder pulses.
//2. **Selection Logic**: The selection is only updated after three pulses (incremented or decremented based on the direction).//
//3. **Resetting Pulse Count**: The `pulseCount` is reset to 0 after the selection has changed.
//
//This implementation ensures that the output selection will only change after three encoder pulses, providing more control over the selection process. Adjust the logic as needed for your specific application!