// Test Arduino pin modes for power consumption

// mode 0
//  Make all pins into inputs (which is pretty much default arduino behaviour)
// Mode 1
//  Make all pins inputs, and enable the internal pull-up resistor
// Mode 2
//  Make all pins outputs, and set them all low
// Mode 3
//  Make all pins outputs and set them all high

// Results
// 0 = 41.1 41.1
// 1 = 31.2 31.1
// 2 = 30.1 30.0
// 3 = 34.9 34.9

int test_mode = 3;

// Using this variable works around a bug in some systems
// See: http://arduino.cc/forum/index.php/topic,59965.msg432768.html
int delay_time = 10000;

void setup() {
  int i;
  for(i = 0; i <= 19; i++) {
    switch(test_mode) {
      case 0:
        pinMode(i, INPUT);
        break;
      case 1:
        pinMode(i, INPUT);
        digitalWrite(i, HIGH);
        break;
      case 2:
        pinMode(i, OUTPUT);
        digitalWrite(i, LOW);
        break;
      case 3:
        pinMode(i, OUTPUT);
        digitalWrite(i, HIGH);
        break;
    }
  }
}

// This is supposed to be a constant 'load'. Looping continuously may
// cause variable current consumption, so I'm hoping a long delay will
// mean the chip is in a 'constant' state.
void loop() {
  delay(delay_time);
}