Building a game console from scratch is entirely doable, and the approach you take depends on how “from scratch” you want to go. At one end, you can wire up a microcontroller to a screen and buttons to create a simple handheld that runs custom games. At the other, you can use a single-board computer like a Raspberry Pi to build something capable of running full game engines. Both paths require the same core decisions: choosing a processor, handling video and audio output, wiring up controls, managing power, and writing or installing the software that ties it all together.
Choosing Your Approach
There are two fundamentally different ways to build a DIY console, and they require very different skill sets.
The microcontroller route means soldering a chip like an ESP32 or STM32 onto a circuit board, wiring it to a small screen and speaker, and programming everything yourself in C or C++. This gives you a true “from scratch” experience. You’ll understand every signal moving through the system. The tradeoff is that you’re limited to simple 2D games, think along the lines of early Game Boy or Atari-era graphics.
The single-board computer route uses a pre-built board like a Raspberry Pi, Orange Pi, or ODROID as the brain of your console. You install an operating system, connect controllers, and either write games in a higher-level language or run emulation software. This gets you to a playable console faster, with far more graphical power, but you’re assembling and configuring rather than building from the ground up.
Most first-time builders start with a single-board computer and graduate to microcontroller builds once they want more control. This article covers both paths.
Picking a Processor
Your processor choice determines everything else: what kind of games you can run, how much power you’ll need, and how complex your wiring gets.
For microcontroller builds, the two most common chips are the ESP32 and various STM32 models. The ESP32 runs at 240 MHz with a dual-core processor, has 520 KB of built-in RAM, and typically comes with 4 MB of flash storage. It also includes Wi-Fi and Bluetooth, which opens the door for wireless controllers or multiplayer. The STM32 family is broader. Entry-level boards like the “Blue Pill” (STM32F103) run at 72 MHz with just 20 KB of RAM and 64 KB of flash, fine for very simple games. Higher-end STM32 chips in the H7 series reach 480 MHz with up to 1 MB of SRAM, putting them in a different league entirely.
For single-board computer builds, ARM-based boards are the standard. The Raspberry Pi 4 is the most popular, but availability has been inconsistent. Alternatives include the Orange Pi 4 LTS, ODROID N2+, and Banana Pi. These boards run full Linux or Android, come with HDMI output, USB ports for controllers, and enough processing power to handle 3D games or retro emulation. Aim for at least 4 GB of RAM. If you want something even more powerful and don’t mind higher cost and power draw, Intel-based single-board computers like the Intel NUC or UDOO BOLT can run desktop-grade games.
Generating Video Output
Getting pixels on a screen is one of the most challenging parts of a from-scratch build. On a single-board computer, this is handled for you through HDMI. On a microcontroller, you have to generate video signals yourself.
The simplest option for microcontroller builds is connecting a small SPI or I2C display, the kind of 2- to 3.5-inch TFT screens commonly sold for Arduino projects. You write pixel data directly to the screen’s memory buffer, and a driver chip on the display handles the rest. Frame rates depend on your SPI bus speed, but 30 to 60 fps is achievable at low resolutions like 320×240.
If you want to output to a TV or monitor, things get more involved. VGA signals require precise timing: you need to generate horizontal and vertical sync pulses alongside color data. Some builders have done this with nothing but discrete logic chips (no processor at all), following the same principles that powered 1970s arcade games like Pong and Breakout. For a microcontroller-based console, you can bit-bang a VGA signal on the ESP32 using its dual cores, one core dedicated to pushing pixels while the other runs game logic. Composite video (the yellow RCA plug) is another option and requires even simpler circuitry: a few resistors to set voltage levels for a black-and-white or color signal.
Adding Sound
If your microcontroller doesn’t have a built-in digital-to-analog converter (DAC), you can create one using pulse-width modulation (PWM) and a simple low-pass filter. At minimum, that’s one resistor and one capacitor connected to a PWM-capable pin. The chip rapidly switches a pin between on and off at varying ratios, and the filter smooths those pulses into an analog voltage that a speaker can reproduce as sound.
The audio quality depends on your PWM resolution. If your chip uses a 16-bit counter for PWM, you get 65,536 distinct voltage levels, enough for CD-quality depth. In practice, most microcontroller game consoles aim for 8-bit sound at sample rates between 8 kHz and 22 kHz, which gives you that classic chiptune character. The ESP32 has two built-in 8-bit DAC channels, so you can skip the PWM workaround entirely and output audio directly.
For single-board computer builds, audio output is handled through HDMI or a 3.5mm headphone jack, no extra circuitry needed.
Wiring Up Controls
A game console needs responsive input. For a custom build, you’ll wire tactile push buttons or a small joystick module to your microcontroller’s GPIO (general-purpose input/output) pins.
The basic wiring scheme connects each button between a GPIO pin and ground, with a pull-up resistor holding the pin high when the button isn’t pressed. When you push the button, the pin gets pulled to ground, and your code detects that transition. Most microcontrollers have internal pull-up resistors you can enable in software, so you often don’t need external resistors at all.
The catch is button bounce. When a mechanical switch closes, the metal contacts vibrate and make/break the connection several times within a few milliseconds. Your processor is fast enough to read each of those bounces as a separate press. The fix is debouncing, either in hardware (a small capacitor across the switch) or in software. A common software approach sets a 15-millisecond cooldown after detecting the first edge change, ignoring any further transitions during that window. After the cooldown expires, the code reads the pin’s actual state and reports a single clean press or release event.
For SBC builds, you can simply plug in USB game controllers or pair Bluetooth gamepads. If you’re building a handheld form factor, you can still wire buttons to the board’s GPIO header and map them to controller inputs in software.
Power Supply for Portable Builds
If you’re building a handheld console, you’ll need a rechargeable lithium-polymer (LiPo) battery and a charging circuit. A 3.7V LiPo cell in the 2000 to 3000 mAh range gives several hours of play on a microcontroller build, or one to three hours on a power-hungry SBC.
The TP4056 is the most commonly used charging module in DIY projects because it costs under a dollar and handles single-cell LiPo charging safely. However, it has a significant limitation: you can’t safely use the device while it’s charging without additional circuitry. To play while plugged in, you need a “power path” or “load sharing” circuit. This typically involves adding a Schottky diode and a P-channel MOSFET to route power from USB directly to your console when plugged in, while simultaneously charging the battery. Dedicated power management ICs like the BQ25606 handle this automatically but are harder to find on pre-made breakout boards.
You’ll also need a voltage regulator to step the battery’s output (which ranges from 3.0V when nearly dead to 4.2V when fully charged) to a stable 3.3V or 5V depending on your components. Low-dropout (LDO) regulators work fine for low-power microcontroller builds. For SBCs drawing more current, a small buck-boost converter is more efficient.
Designing a Custom Circuit Board
Once you’ve prototyped your console on a breadboard, you can design a proper printed circuit board to make it permanent and compact. Free tools like KiCad let you lay out your schematic and route traces.
When designing for a handheld, keep your board dimensions aligned with standard panel sizes offered by PCB manufacturers, this significantly reduces cost. Most budget fabrication services (JLCPCB, PCBWay, PCBCart) will produce a two-layer board for a few dollars per set of five. Four-layer boards cost more but give you cleaner power delivery and signal routing, which matters if you’re running high-speed video signals. Standard FR4 material at 1.6mm thickness covers most needs. If you’re designing a very thin handheld, note that boards thinner than 0.6mm to 0.7mm have manufacturing constraints around scoring and cutting.
For a first build, a two-layer board is more than adequate. Place your microcontroller, display connector, audio output, button pads, battery connector, and charging circuit on one board, and you have a complete handheld console in a package small enough to fit inside a 3D-printed case.
Writing the Software
The software side splits along the same hardware divide.
For microcontroller builds, you’re typically writing bare-metal C or C++ using the chip manufacturer’s SDK. The ESP32 uses the ESP-IDF framework (or can be programmed through Arduino IDE for simpler projects). STM32 chips use STM32CubeIDE with HAL libraries. Your game code handles everything: reading button inputs, updating game state, rendering frames to the display buffer, and mixing audio samples. There’s no operating system underneath unless you choose to run a lightweight real-time OS like FreeRTOS, which helps manage tasks like keeping audio output steady while the game logic runs.
For SBC builds, you install a Linux distribution (Ubuntu, Raspberry Pi OS, or a gaming-focused distro like RetroPie or Lakka) onto a microSD card or onboard storage. From there, you can write games in Python with Pygame, in C++ with SDL2, or use a full game engine like Godot. If your goal is retro emulation, RetroPie bundles dozens of emulators with a polished controller-friendly interface. Installing an OS on something like an Orange Pi 4 LTS typically means burning the image to a TF (microSD) card, booting from it, and optionally installing to the board’s built-in eMMC storage for faster performance.
Putting It All Together
A practical build order keeps you from getting stuck. Start with your processor on a breadboard, get it blinking an LED, then displaying something on screen. Add button inputs next so you can interact with what’s on the display. Layer in audio once the visual side works. Write a simple game (Pong, Snake, or Breakout are classics for a reason) to validate that inputs, display, and sound all work together smoothly. Only then move to designing a PCB and enclosure.
For the enclosure, 3D printing is the most accessible option. Thingiverse and Printables have dozens of handheld console cases designed for common boards and screen sizes. If you don’t have a printer, online services will print and ship a case for $10 to $30 depending on size and material. A well-designed case with proper button cutouts, a screen bezel, and a battery compartment transforms a rats-nest of wires into something that actually feels like a console.
Budget-wise, a microcontroller-based handheld can come together for $15 to $40: a few dollars for the chip, $5 to $10 for a small screen, a couple dollars for buttons and passive components, and $5 to $10 for a battery and charging board. An SBC-based console runs $50 to $150 depending on the board, controllers, and case. Either way, the real investment is time. Expect to spend a few weekends on a first build, longer if you’re learning electronics or programming along the way.