Rotary Encoder trying to get a fixed count 0-10 then 10-0

Using Arduino Programming Questions
#1

Hi All,

I am trying to get my rotary encoder to work for a future project i have in mind. What i want the encoder to do is print to serial the counts starting from 0 up to 10, then stop. then if i turn the encoder the opposite way it goes down back to 0 then stops. Much like a volume knob on an amplifier so you have a min and a max value.
The attached code somewhat works but it goes from 0-10 the gets stuck.
could somebody please have a look at my code and advise me where it is wrong.
Much appreciated

Thanks

// Rotary encoder example.
// Wiring: Connect common pin of encoder to ground.
// Connect pins A and B (the outer ones) to pins 2 and 3 (which can generate interrupts)

volatile boolean fired = false;
volatile long rotaryCount =0;

// Interrupt Service Routine
void isr ()
{
static boolean ready;
static unsigned long lastFiredTime;
static byte pinA, pinB;  

// wait for main program to process it
  if (fired)
    return;
    
  byte newPinA = digitalRead (2);
  byte newPinB = digitalRead (3);
  
  // Forward is: LH/HH or HL/LL
  // Reverse is: HL/HH or LH/LL
  
  // so we only record a turn on both the same (HH or LL)
  
  if (newPinA == newPinB)
    {
    if (ready)
      {
      long increment = 1;
      unsigned long now = millis ();
      unsigned long interval = now - lastFiredTime;
      lastFiredTime = now;
      
      if (interval < 10)
        increment = 5;
      else if (interval < 20)
        increment = 3;
      else if (interval < 50)
        increment = 2;
        
        if (newPinA == HIGH)
        {
          if (pinA == LOW)
          {
            if (rotaryCount + increment <= 10)
            rotaryCount + increment + 1;
          }
            else if (rotaryCount - increment >= 10)
            rotaryCount --;
          }
          else
          {
if (pinA == LOW)
            {
              if (rotaryCount - increment >= 10)
              rotaryCount --;
            }
              else 
              {
                if (rotaryCount + increment <= 10)
              rotaryCount ++;
            }
            fired = true;
            ready = false;
          }
        }
        else
        ready = true;
        pinA = newPinA;
        pinB = newPinB;
      }
    }


void setup ()
{
  digitalWrite (2, HIGH);   // activate pull-up resistors
  digitalWrite (3, HIGH); 
  
  attachInterrupt (0, isr, CHANGE);   // pin 2
  attachInterrupt (1, isr, CHANGE);   // pin 3

  Serial.begin (9600);
}  // end of setup

void loop ()
{

  if (fired)
    {
    Serial.print ("Count = ");  
    Serial.println (rotaryCount);
    fired = false;
  }  // end if fired

}  // end of loop
#2

In the isr() function, if rotaryCount becomes 11, set it to 10. That way, the count can never exceed 10. If rotaryCount becomes -1, set it to 0. That way, the count can never be less than 0.

#3