Sabotage

// MakerNest Origins · bench 06 · a push button that counts, and a second one that undoes
// Button one on row 12 adds one. Button two on row 10 takes one away.
// No resistors: the board's own pull-up keeps each pin HIGH until a button pulls it to G.

const int ADD_PIN = 12;
const int UNDO_PIN = 10;
const unsigned long SETTLE = 30;   // milliseconds to ignore after a press. Try 0.

int count = 0;
bool addWasDown = false;
bool undoWasDown = false;
unsigned long lastChange = 0;

void setup() {
  pinMode(ADD_PIN, INPUT_PULLUP);
  pinMode(UNDO_PIN, INPUT_PULLUP);
  Serial.begin(9600);
  Serial.println("Count: 0");
}

void loop() {
  bool addDown = digitalRead(ADD_PIN) == LOW;     // pressed pulls the pin LOW
  bool undoDown = digitalRead(UNDO_PIN) == LOW;

  if (millis() - lastChange >= SETTLE) {
    if (addDown && !addWasDown) {
      count = count + 1;
      Serial.print("Count: ");
      Serial.println(count);
      lastChange = millis();
    }
    if (undoDown && !undoWasDown && count > 0) {
      count = count - 1;
      Serial.print("Count: ");
      Serial.println(count);
      lastChange = millis();
    }
    addWasDown = addDown;
    undoWasDown = undoDown;
  }
}

// MakerNest Origins · bench 02 · an LED that switches on below a number
// The light sensor on A0 gives a number. Below LINE, the LED on row 12 comes on.
// Open Tools, Serial Monitor (9600) to watch the number.

const int SENSOR_PIN = A0;   // light sensor and 10k resistor meet here
const int LED_PIN = 12;      // the LED's long leg is wired to row 12
const int LINE = 300;        // your number: below this, the LED comes on

void setup() {
  pinMode(LED_PIN, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  int light = analogRead(SENSOR_PIN);   // 0 is black dark, 1023 is very bright
  Serial.println(light);

  if (light < LINE) {
    digitalWrite(LED_PIN, HIGH);
  } else {
    digitalWrite(LED_PIN, LOW);
  }
  delay(500);
}

// MakerNest Origins · bench 08 · traffic lights with your own timings
// Red on row 12, yellow on row 13, green on row 10. Change the four numbers to make
// your own crossing. All times are in milliseconds: 1000 is one second.

const int RED_PIN = 12;
const int YELLOW_PIN = 13;
const int GREEN_PIN = 10;

const unsigned long RED_TIME = 5000;
const unsigned long RED_AND_YELLOW_TIME = 1500;
const unsigned long GREEN_TIME = 5000;
const unsigned long YELLOW_TIME = 2000;

void lights(bool red, bool yellow, bool green) {
  digitalWrite(RED_PIN, red ? HIGH : LOW);
  digitalWrite(YELLOW_PIN, yellow ? HIGH : LOW);
  digitalWrite(GREEN_PIN, green ? HIGH : LOW);
}

void setup() {
  pinMode(RED_PIN, OUTPUT);
  pinMode(YELLOW_PIN, OUTPUT);
  pinMode(GREEN_PIN, OUTPUT);
}

void loop() {
  lights(true, false, false);   // stop
  delay(RED_TIME);
  lights(true, true, false);    // get ready
  delay(RED_AND_YELLOW_TIME);
  lights(false, false, true);   // go
  delay(GREEN_TIME);
  lights(false, true, false);   // stop if you can
  delay(YELLOW_TIME);
}

// MakerNest Origins · bench fault 5
// This is bench 02's sketch, and the circuit on the page is wired exactly like bench 02.
// Something is broken. Don't change anything until you know what.

const int SENSOR_PIN = A0;
const int LED_PIN = 10;
const int LINE = 300;

void setup() {
  pinMode(LED_PIN, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  int light = analogRead(SENSOR_PIN);
  Serial.println(light);

  if (light < LINE) {
    digitalWrite(LED_PIN, HIGH);
  } else {
    digitalWrite(LED_PIN, LOW);
  }
  delay(500);
}