Week 4 : Embedded Programming

In week 4, we focused on embedded programming. We worked with microcontrollers and learned how to write code that interacts with hardware components. We also learned how to solder electronic components and understand GPIO (General Purpose Input/Output) pins.

This week, we completed our second group assignment. You can see the group assignment at the following link: Group Assignment

For the embedded programming assignment, I worked with two microcontrollers: Arduino Uno and Seeed ESP32.

	Arduino Uno	Seeed Studio XIAO ESP32C3
VERSION	UNO R3	ESP32C3
# OF PINS	14 digital input/output pins 6 analog pins	11 digital I/O 4 of them could be Analog
MICROCONTROLLER	ATMega328P	ESP32-C3 SoC
OSCILLATOR	16 MHz crystal oscillator	17.5 MHz crystal oscillator
DATA SHEET	Arduino Uno R3 Datasheet	ESP32-C3 Datasheet

First, I made a Dino Run game on the Arduino Uno to focus on the physical connections and understand them better.

Here are the components that I used:

I followed the instructions in the tutorial to build and test the Dino Run game. Here is the tutorial link: Dino Run Game Tutorial

Before uploading the code, don't forget to check the microcontroller port number in the device monitor under the port section, then select the correct port type.

💡 Note: Put the header file in the same folder as the .ino file and change the include path #include <LiquidCrystal_I2C.h> to #include "LiquidCrystal_I2C.h". Alternatively, you can keep it as is, but place the header file inside the Arduino IDE lib directory.

Then I tried to connect the Arduino Uno to the serial monitor by editing the Dino game code. Since I wanted to show the output in color, I had to download PuTTY.

💡 Note: Make sure to set the correct COM port in the Arduino IDE and the correct baud rate in PuTTY.

💡 Note: When you open PuTTY, make sure to close any other terminal or serial monitor that may be running to avoid connection conflicts on the same port.

You can see the full code using this link Week 4 Dino Game Code

And you can download the code from here

After I understood the hardware part, I decided it was time to write my own code.

I chose to write code for a Reaction Time Test using the Arduino Uno microcontroller. The code measures the time it takes for a user to react to a visual stimulus (an LED turning on) and displays the reaction time on the serial monitor and LCD.

The system configures all hardware pins, starts Serial communication, and initializes the LCD. It reads the saved best reaction time from EEPROM and resets it if the value is invalid. Finally, it waits for the user to press the button before starting the game.

The LCD displays “READY…”, and LEDs light up sequentially with buzzer sounds. This creates a visual and audio countdown to prepare the player.

After the countdown, the program waits for a random time between 1–4 seconds. This prevents the player from predicting when the signal will appear.

All LEDs turn on and a buzzer tone plays to indicate the start of the reaction test. At that exact moment, the program records the start time using millis().

When the button is pressed, the system records the end time and calculates the reaction speed. It compares the result with the stored best time and updates EEPROM if a new record is achieved.

The LCD shows the current reaction time along with the best recorded time. After a short delay, the LEDs turn off and the system waits to begin a new round.

You can see the full code using this link Week 4 Reaction Time Test Code. And you can download the code from here.

For this assignment, I learned how to solder electronic components. Our instructor gave us a short session on how to solder electronics. Here is a helpful reference: Soldering Guide

I soldered the ESP32-C3 board using a soldering iron and solder wire. I made sure to connect all the pins correctly and securely.

Before Soldering

After Soldering

I first tried to run my code on the ESP32 board using the pin numbering shown on the board in the image below.

Week 4 : Embedded Programming

In week 4, we focused on embedded programming. We worked with microcontrollers and learned how to write code that interacts with hardware components. We also learned how to solder electronic components and understand GPIO (General Purpose Input/Output) pins.

1. Group Assignment

This week, we completed our second group assignment. You can see the group assignment at the following link: Group Assignment

2. Individual Assignment

For the embedded programming assignment, I worked with two microcontrollers: Arduino Uno and Seeed ESP32.

Arduino Uno

A. First Test

First, I made a Dino Run game on the Arduino Uno to focus on the physical connections and understand them better.

Here are the components that I used:

I followed the instructions in the tutorial to build and test the Dino Run game. Here is the tutorial link: Dino Run Game Tutorial

Before uploading the code, don't forget to check the microcontroller port number in the device monitor under the port section, then select the correct port type.

Then I tried to connect the Arduino Uno to the serial monitor by editing the Dino game code. Since I wanted to show the output in color, I had to download PuTTY.

You can see the full code using this link Week 4 Dino Game Code

And you can download the code from here

B. Second Test

After I understood the hardware part, I decided it was time to write my own code.

I chose to write code for a Reaction Time Test using the Arduino Uno microcontroller. The code measures the time it takes for a user to react to a visual stimulus (an LED turning on) and displays the reaction time on the serial monitor and LCD.

Code flow:

1. Initialization Phase (Setup)

2. Ready & Countdown

3. Random Delay (Fairness Step)

4. GO Signal & Start Timing

5. Reaction Measurement & Record Check

6. Display Results & Reset

Seeed Studio XIAO ESP32C3

A. Soldering

For this assignment, I learned how to solder electronic components. Our instructor gave us a short session on how to solder electronics. Here is a helpful reference: Soldering Guide

I soldered the ESP32-C3 board using a soldering iron and solder wire. I made sure to connect all the pins correctly and securely.

B. Understanding GPIO

I first tried to run my code on the ESP32 board using the pin numbering shown on the board in the image below.

It didn’t work at first. After some research, I found the correct GPIO pins and tried them, and they worked perfectly.

Here is my conversation with ChatGPT, which helped me fully understand the GPIO mapping: View the full conversation.

You can find the ESP32 GPIO numbers in the getting started documentation.

C. Code

You can see the full code using this link ESP32 Code

And you can download the code from here