DIY Concorde servo panel

cpp
//pulup resistors
if(digitalRead(pinA) == HIGH){
  //The terminals at pinA aren't connected thus we are in state 0
}

//If using pull down resistors
//if(digitalRead(pinA) == LOW){
  //The terminals at pinA aren't connected thus we are in state 0
//}

We could then check whether or not the first state was set by checking if the 1 and 2 terminals are connected. The downside of this would be that in the second state, these terminals are connected as well. We could check if the first terminal is connected and if the third and fifth terminals are connected. But this would lead to unnecessary checks. It will be wiser to check if the third and fourth terminals are connected. We know for a fact that these terminals connect when we are in the second state.
//pulup resistors
if(digitalRead(pinC) == LOW){
  //The terminals at pinB are connected thus we are in state 2
}

//If using pull down resistors
//if(digitalRead(pinC) == HIGH){
  //The terminals at pinB are connected thus we are in state 2
//}
In theory, we could add a third check to see whether or not we are in the first state. But if we aren't in state two, and we aren't in state zero. The only thing that would be left is state 1. So in this instance, a simple else statement would suffice.
//pulup resistors
if(digitalRead(pinA) == HIGH){
  //The terminals at pinA aren't connected thus we are in state 0
}

//If using pull down resistors
//if(digitalRead(pinA) == LOW){
  //The terminals at pinA aren't connected thus we are in state 0
//}

//pulup resistors
if(digitalRead(pinC) == LOW){
  //The terminals at pinC are connected thus we are in state 2
}

//If using pull down resistors
//if(digitalRead(pinC) == HIGH){
  //The terminals at pinC are connected thus we are in state 2
//}

else{
  //Everything else has been checked so the only thing that is left is state 1
}

cpp
#include <BitsAndDroidsFlightConnector.h>

BitsAndDroidsFlightConnector connector = BitsAndDroidsFlightConnector();

enum states {
  LEFT,
  UP,
  RIGHT
};

const byte testPin = 53;

const byte redLEDs[] = { 8, 9, 10, 11 };
const byte greenLEDs[] = { 12, 51, 50, 52 };

const byte upperSwitch[] = { 3, 4, 5 };
const byte lowerSwitch[] = { 6, 7, 8 };

byte oldLowerState;
byte oldUpperState;
byte oldTestState;

long timer0State = 0;

void setup() {
  Serial.begin(115200);

  for (auto& pin : redLEDs) {
    pinMode(pin, OUTPUT);
  }

  for (auto& pin : greenLEDs) {
    pinMode(pin, OUTPUT);
  }

  for (auto& pin : upperSwitch) {
    pinMode(pin, INPUT_PULLUP);
  }

  for (auto& pin : lowerSwitch) {
    pinMode(pin, INPUT_PULLUP);
  }

  pinMode(testPin, INPUT_PULLUP);
}

void loop() {
  connector.dataHandling();
  checkUpperSwitch();
  checkLowerSwitch();
  checkTestState();

}


void checkLowerSwitch() {
  //My top switch has 4 positions while the lower only has 3
  //I'd recommend to buy two 3 position switches to make your life easier.
  //Pos 0 == all off | pos 1 == 6 connected | pos 2 == 6,7,8 connected
  byte currentState;
  //6 is always on unless we are in position 0, this will be our first check
  if (digitalRead(lowerSwitch[0]) == HIGH && digitalRead(lowerSwitch[1]) == HIGH && digitalRead(lowerSwitch[2]) == HIGH) {
    //I've added a custom command to the connector with prefix 6013
    //0 is the switch state we want to set the ingame switch to
    currentState = LEFT;
  }
  //pin 8 will only be LOW if the switch is in position 2
  else if (digitalRead(lowerSwitch[2]) == LOW) {
     currentState = RIGHT;
  }
  //if we checked all these sentences we know for a fact the other state will be 1
  //(unless there would be an error in our wiring)
  else {
     currentState = UP;
  }
  if(currentState != oldLowerState){
    Serial.println("6013 " +  String(currentState));
    oldLowerState = currentState;
    delay(100);
    setGreenLightState();
  }
}

//The states differ between 3 and 4 position switches,
//that is why I've used 2 functions
void checkUpperSwitch() {
  //I use position 1,2 and 3. They all match 1 on 1 with their states. If they are LOW that position is set.
  byte currentState;

  if (digitalRead(upperSwitch[1]) == LOW) {
    currentState = RIGHT;
  } else if (digitalRead(upperSwitch[2]) == LOW) {
    currentState = UP;
  } else {
    if(timer0State==0){
      timer0State = millis();
    }
    currentState = LEFT;
  }

  //Because switchting states adds a gap where all states are HIGH I've added a timer
  //This filters out the incorrect readings for the 0 state when turning the dial
  long currentTime = millis();

  if(currentState != oldUpperState){
    if((currentState == 0 && abs(currentTime - timer0State) > 500) || currentState == 1 || currentState == 2){
      timer0State = 0;
      Serial.println("6012 " + String(currentState));
      oldUpperState = currentState;
      delay(200);
      setGreenLightState();
    }
  }
}

void setGreenLightState(){
 
  switch(oldLowerState){
    case LEFT:{
      digitalWrite(greenLEDs[3], HIGH);
      digitalWrite(greenLEDs[2], LOW);
      break;
    }
    case UP:{
      digitalWrite(greenLEDs[2], HIGH);
      digitalWrite(greenLEDs[3], HIGH);
      break;
    }
    case RIGHT:{
      digitalWrite(greenLEDs[2], HIGH);
      digitalWrite(greenLEDs[3], LOW);
      break;
    }
  }
   switch(oldUpperState){
    case LEFT:{
      digitalWrite(greenLEDs[0], HIGH);
      digitalWrite(greenLEDs[1], LOW);
      break;
    }
    case UP:{
      digitalWrite(greenLEDs[0], HIGH);
      digitalWrite(greenLEDs[1], HIGH);
      break;
    }
    case RIGHT:{
      digitalWrite(greenLEDs[1], HIGH);
      digitalWrite(greenLEDs[0], LOW);
      break;
    }
  }
  
}

void checkTestState(){
  byte currentState = digitalRead(testPin);
  if(currentState != oldTestState){
    if(currentState == LOW){
      for(auto & led : greenLEDs){
        digitalWrite(led, HIGH);
      }
      //The red lights are only in when the testSwitch is triggered
      //This makes it correspond with the ingame trigger without retrieving game data
      for(auto & led : redLEDs){
        digitalWrite(led, HIGH);
      }
      Serial.println("6015 1");
    } else{
      //Make sure to set the lights back to the correct state
      setGreenLightState();
       for(auto & led : redLEDs){
        digitalWrite(led, LOW);
      }
      Serial.println("6015 0");
    }
    
    oldTestState = currentState;
  } 
  
}