My first DIY - A Macro Pad with a Micro Trial by Fire

Exploring Embedded Systems: My Journey Building an ESP32-C3 Macro Pad

Introduction: Expanding My Skillset

By day, I work in finance, focusing on derivatives and Python-based automation. But outside of that world, I’ve always been drawn to the tangible—the satisfaction of building something physical, something that bridges the gap between code and hardware. My recent project, an ESP32-C3 macro pad, was an opportunity to explore embedded systems, deepen my understanding of electronics, and expand my technical skillset beyond software.

This wasn’t about transitioning careers or abandoning my existing expertise. It was about curiosity, challenge, and the desire to create something from the ground up.

Starting with Limited Knowledge

I came into this project with a solid foundation in Python and problem-solving, but almost no experience in C++ or hardware design. Terms like "ground noise, " "pull-up resistor, " and "debounce delay" were new to me. Yet, rather than seeing this as a limitation, I treated it as a chance to learn.

The project began on a breadboard and a Wokwi simulation, where I wired an ESP32-C3, buttons, and a potentiometer. Following tutorials and experimenting with basic circuits, I gradually built confidence. When the buttons responded and the potentiometer returned stable readings, I felt, innocently, that I was on the right track.

Initial breadboard prototype—where the journey began.

The Move to PCB: Lessons in Debugging

Soldering the components onto a PCB was where theory met reality. Almost immediately, I encountered issues: buttons responded intermittently, and the potentiometer’s readings were erratic. The breadboard had been forgiving; the PCB was not.

Schematic:

PCB:

After systematic debugging—testing connections, reviewing schematics, and researching common issues—I identified the problem: ground noise. The digital button grounds were converging at the potentiometer’s GND pin, causing interference. The fix was straightforward: a direct ground wire from the potentiometer to the ESP32-C3’s GND pin. This small change stabilized the circuit, reinforcing a fundamental lesson: grounding is not just a detail; it’s the foundation of a reliable design.

The soldered PCB, where real-world challenges emerged.

Coding in a New Language

With a background in Python, writing Arduino-like C++ was a shift. The syntax was unfamiliar, but the logic was transferable. I used INPUT_PULLUP for button inputs, implemented debounce delays to filter noise, and relied on the serial monitor for debugging. The potentiometer, now stable, provided consistent analog readings, which I integrated into the macro pad’s functionality.

This experience underscored the value of adaptability. While I wasn’t fluent in C++, I could apply my problem-solving skills to navigate the learning curve.

Key Takeaways

Grounding is Critical: A stable ground is essential for reliable hardware. Overlooking it can lead to unpredictable behavior.

• Grounding is Critical: A stable ground is essential for reliable hardware. Overlooking it can lead to unpredictable behavior.

Debugging is Iterative: Hardware issues are rarely obvious. Patience and methodical testing are key.

• Debugging is Iterative: Hardware issues are rarely obvious. Patience and methodical testing are key.

Documentation Matters: Keeping detailed notes—on wiring, code changes, and debugging steps—saves time and reduces frustration.

• Documentation Matters: Keeping detailed notes—on wiring, code changes, and debugging steps—saves time and reduces frustration.

Learning is a Process: Expanding into embedded systems wasn’t about mastering everything at once. It was about applying existing skills in new ways and embracing the learning journey.

• Learning is a Process: Expanding into embedded systems wasn’t about mastering everything at once. It was about applying existing skills in new ways and embracing the learning journey.

Why Build It Yourself?

In a world of pre-built solutions, designing and building a custom macro pad might seem unnecessary. But the real value lies in the process: the satisfaction of solving problems, the deeper understanding of how hardware and software interact, and the creation of something tailored to your needs.

This project also reinforced my appreciation for DIY culture. Whether it’s integrating custom devices with platforms like Home Assistant or experimenting with MQTT, there’s a unique fulfillment in building tools that fit your exact requirements—even if the path is occasionally challenging.

What’s Next?

I’m excited to continue exploring embedded systems, particularly with the ESP32-S3, which offers native HID support and opens up new possibilities for macro functionality and custom input devices. The journey doesn’t end here; it’s an ongoing process of refinement, experimentation, and learning.

The next phase: ESP32-S3 with native HID support.

Final Thoughts

This project was more than just building a macro pad. It was about stepping outside my comfort zone, applying analytical thinking to a new domain, and discovering the rewards of hands-on creation. For anyone considering a similar exploration—whether you’re coming from finance, software, or another field—I’d encourage you to dive in. The challenges are real, but so are the rewards.