Also known as: Arduino
Arduino is a widely used family of beginner-friendly microcontroller boards and the open-source ecosystem of tools and code built around them.1
Overview
An Arduino program is called a sketch. The simple Arduino IDE — with its two-function skeleton of setup() and loop() — plus a huge library and “shield” ecosystem of plug-in add-on boards, is what made microcontrollers approachable to hobbyists and students. Classic boards are 8-bit and modest in speed and memory, but that is enough for sensors, motors, and small projects.
The project began in Italy in 2005 as open-source hardware: the board schematics, the IDE, and the core libraries are all freely available, which spawned countless clones and derivatives. That openness is central to Arduino’s identity — the name refers as much to the software and community as to any one board.
The classic lineup runs on Microchip’s AVR/ATmega chips (the Uno’s ATmega328P is the icon), while newer official boards move to 32-bit ARM Cortex-M parts and other cores for more speed and memory.
Board line-up
Arduino spans a range of form factors and cores, but they share the same sketch model and IDE:
| Board | Core | Clock | Flash | Notable |
|---|---|---|---|---|
| Uno / Nano | 8-bit AVR (ATmega328P) | 16 MHz | 32 KB | The classic beginner board |
| Mega 2560 | 8-bit AVR (ATmega2560) | 16 MHz | 256 KB | Many I/O pins |
| Micro / Leonardo | 8-bit AVR (ATmega32U4) | 16 MHz | 32 KB | Native USB |
| Nano 33 / Portenta | 32-bit ARM Cortex-M | 64+ MHz | 256 KB+ | BLE, more RAM |
Where it fits
Arduino sits at the gentle end of embedded computing: you wire components to its GPIO pins, write a sketch, and flash it onto the board. The ecosystem’s tooling has spread well beyond the original boards — many other microcontrollers, including the ESP32, can be programmed with the Arduino IDE too. In an SDR context an Arduino makes a handy GPIO helper — switching an antenna relay, reading a temperature sensor, or blinking a status light beside a capture node — while GopherTrunk itself runs on a full computer. These tiny boards also drive the kinds of small radios that fill the airwaves GopherTrunk listens to.