Problem with Toggle Switch Input

obtain a single output variable from the FOR loop

The data variable is the single output variable. Untested example.

int data = 0;  // added  **declare globally** 

void display_pin_values()
{
  //start marker
  //Serial.print("<");

  //Serial.print("Experiment:\r\n");
  for (int i = 0; i < DATA_WIDTH; i++)
  {

    if ((pinValues >> i) & 1) {
      Serial.print("1");
      bitSet(data, i);  // added
    }
    else
      Serial.print("0");
      bitClear(data, i);  // added
  }
  //end marker
  //Serial.print(">");
  
  Serial.print("\r\n");
}