unsigned long now;
unsigned int counter;

/* reserved for two-in-one version
const byte ledPins[numLeds] = {2, 3, 4, 5};
const byte buttonPins[numLeds] = {7, 8, 9, 10};
*/

const byte muxOutput = 12;  // *input* for COM CD4067 output

# define NT 16  // up to... 16

# define RATE 177

void setup() {
  Serial.begin(115200);
  Serial.println("hi Mom!");

  pinMode(13, OUTPUT);
  pinMode(A5, INPUT_PULLUP);

  DDRC |= 0xf;  // A0 .. A3 outputs
  pinMode(muxOutput, INPUT_PULLUP);    // probably use a real resistor
}

void loop() {

// poor man's logic probe
  digitalWrite(13, digitalRead(A5));

  static unsigned long lastTime;
  now = millis();

// loop rate - full processor attention here


// and throttled

  if (now - lastTime < RATE) return;
  lastTime = now;

// once per RATE milliseconds past here
  Serial.print(counter), counter++;
  Serial.print("  ");
  Serial.print(inReader(), BIN);
  Serial.println("");
}

unsigned int inReader()
{
  unsigned int result = 0;

  for (byte ii = 0; ii < NT; ii++) { 
    PORTC &= 0xf0;
    PORTC |= ii;

//delay(200);
//Serial.println(digitalRead(muxOutput));

    result <<= 1;
    if (digitalRead(muxOutput) == HIGH) result |= 1;
  }

  return result;
}