HERO

### Understanding the HERO Board: A Beginner’s Lesson by Astrid and Gear

**Setting:** Astrid and Gear are in their cozy workshop, filled with various gadgets and mechanical components.

**Astrid:** “Gear, I’ve heard about the HERO board, but I’ve never used one before. Can you explain what it is and how it works?”

**Gear:** “Of course, Astrid! The HERO board is a clone of the Arduino Uno R3, a popular microcontroller board used for building electronic projects. It’s a fantastic tool for beginners and experts alike because it makes it easy to create interactive electronic

devices.”

**Astrid:** “Okay, but what exactly does a microcontroller board do?”

**Gear:** “A microcontroller board is like a small computer that can control other electronic components. You can program it to read inputs, like sensors, and control outputs, like lights and motors. It’s the brain of your electronic projects.”

**Astrid:** “That sounds interesting. But how do I use it in my projects?”

**Gear:** “Let’s start with the basics. The HERO board has several important parts, called headers, where you can connect other components. Let’s go through them one by one.”

**Astrid:** “Sure, tell me about the headers.”

**Gear:** “Alright! The HERO board has different types of pins grouped into headers. They are digital I/O pins, analog input pins, power pins, and special function pins.”

1. **Digital Input/Output (I/O) Pins:**

– **Gear:** “These pins allow you to connect digital devices, like LEDs, buttons, and sensors. The HERO board has 14 digital I/O pins, numbered 0 to 13. You can use them for both input and output.”

– **Astrid:** “How do I know whether to use them as input or output?”

– **Gear:** “You can specify that in your code using the `pinMode` function. For example, if you’re connecting an LED, you’ll set the pin as an output. If you’re connecting a button, you’ll set the pin as an input.”

– **Use Case:**

– **Gear:** “Remember the time we wanted to create a warning system for when the city’s gates were opened? We used digital pins to read the state of the button that was pressed when the gate was opened and to control an LED that indicated the status.”

2. **Analog Input Pins:**

– **Gear:** “These pins are used for reading analog signals, like those from a temperature sensor. The HERO board has 6 analog input pins, labeled A0 to A5.”

– **Astrid:** “What’s the difference between analog and digital signals?”

– **Gear:** “Digital signals are either on or off, like a light switch. Analog signals can have a range of values, like a dimmer switch that can vary the brightness of a light.”

– **Use Case:**

– **Gear:** “When we built the light-sensitive alarm to detect the presence of shadows during the festival, we used an analog input pin to read the value from a photoresistor. This helped us determine how much light was in the area.”

3. **Power Pins:**

– **Gear:** “The power pins provide power to your components. The HERO board has several power pins, including 5V, 3.3V, and GND (ground).”

– **Astrid:** “When would I use 5V versus 3.3V?”

– **Gear:** “Different components require different voltages to operate. For example, some sensors work at 3.3V while others work at 5V. Always check the specifications of your components.”

– **Use Case:**

– **Gear:** “When we powered the motion sensor for our security system, we connected it to the 5V pin because it required 5 volts to operate correctly.”

4. **Special Function Pins:**

– **Gear:** “There are some pins with special functions, like the RX and TX pins for serial communication (0 and 1), the reset pin, and the AREF pin.”

– **Astrid:** “What are RX and TX used for?”

– **Gear:** “RX (receive) and TX (transmit) are used for serial communication, which allows the HERO board to communicate with other devices like computers or other microcontrollers.”

– **Use Case:**

– **Gear:** “When we needed to send data from our HERO board to the computer to monitor the environmental conditions in Cogsworth City, we used the RX and TX pins for serial communication.”

5. **9V Battery Jack and USB Connector:**

– **Gear:** “The HERO board can be powered in different ways. One way is through the USB connector. When you connect the HERO board to your computer using a USB cable, it not only allows you to upload programs but also powers the board.”

– **Astrid:** “So, I can just use the USB connection to power the board?”

– **Gear:** “Yes, but there are times when you need the board to be powered without being connected to a computer. That’s where the 9V battery jack comes in. You can connect a 9V battery to this jack to power the board.”

– **Use Case:**

– **Gear:** “Remember when we made the portable weather station to monitor the climate in different parts of the city? We used a 9V battery to power the HERO board so we could move it around easily.”

– **Astrid:** “What are the benefits of using a 9V battery?”

– **Gear:** “Using a 9V battery makes your project portable, and it’s useful when there’s no access to a USB power source. Just make sure to use a voltage regulator to avoid damaging the board with too much power.”

**Astrid:** “That’s a lot of information! How do I remember all this?”

**Gear:** “Don’t worry, Astrid. You’ll get used to it with practice. Let’s start with a simple project to make things clearer. We’ll create a project using a digital pin to control an LED and an analog pin to read a value from a photoresistor.”

**Project: Controlling an LED and Reading a Sensor**

1. **Connect the LED:**

– **Gear:** “Connect the longer leg (anode) of the LED to digital pin 13 on the HERO board. Connect the shorter leg (cathode) to GND.”

2. **Connect the Photoresistor:**

– **Gear:** “Connect one end of the photoresistor to 5V and the other end to A0. Then, connect a 10k ohm resistor from A0 to GND. This will create a voltage divider.”

3. **Write the Code:**

– **Gear:** “Open the Arduino IDE and write this code:”

“`cpp

void setup() {

pinMode(13, OUTPUT); // Set pin 13 as an output for the LED

Serial.begin(9600); // Start serial communication for debugging

}

void loop() {

int sensorValue = analogRead(A0); // Read the value from the photoresistor

Serial.println(sensorValue); // Print the sensor value to the serial monitor

if (sensorValue < 500) { // If the sensor value is less than 500

digitalWrite(13, HIGH); // Turn the LED on

} else {

digitalWrite(13, LOW); // Turn the LED off

}

delay(100); // Wait for 100 milliseconds

}

```

4. **Upload the Code:**

- **Gear:** "Connect the HERO board to your computer using the USB cable. Select the correct board and port in the Arduino IDE, then click the upload button."

5. **Test the Project:**

- **Gear:** "Once the code is uploaded, open the serial monitor in the Arduino IDE. Cover and uncover the photoresistor to see the changes in the sensor value and watch the LED turn on and off."

**Astrid:** "Wow, it works! This is so cool, Gear. Thanks for explaining everything."

**Gear:** "You're welcome, Astrid. The HERO board is a powerful and versatile tool. With it, you can create all sorts of amazing projects. Remember to keep experimenting and learning!"

**Astrid:** "I will, Gear. This is just the beginning of my journey with

the HERO board!"