Arduino Mega 2560 Rev3

Jargon buster

Plain-language definitions for the technical terms used above.

Bootloader

Small starter software on a microcontroller that lets new code be uploaded before the main program runs. Knowing how to enter bootloader mode matters when you need to program the board or recover it after a faulty sketch.

DC

DC means direct current, where electricity flows in one constant direction, as supplied by batteries, USB ports and many plug-pack power supplies. When a product specifies DC, it runs from a DC supply rather than mains AC, so you need to provide the correct voltage and polarity.

EEPROM

A type of non-volatile memory that keeps stored data even when power is turned off. In a sensor module, it can be used to store settings or calibration data so they do not need to be re-entered every time.

Flash memory

Flash memory is non-volatile memory that retains stored data even when power is removed, and can be erased and rewritten in blocks. It lets data such as firmware, settings or saved records persist across power cycles.

GPS

The US satellite navigation system used by GNSS receivers to calculate position and time. Support for GPS is important because it is widely available and often used together with other constellations for more reliable positioning.

LED

A light-emitting diode (LED) is a small electronic component that emits light when current flows through it in the correct direction. Because it only conducts one way, its polarity matters, and a through-hole LED must be soldered the correct way around to light up.

microcontroller

A microcontroller is a small computer on a single chip that runs a stored program and controls connected inputs and outputs such as buttons, sensors, displays and communication interfaces. In a device built around one, it is the part that executes the code and coordinates the device's behaviour.

PWM

Pulse Width Modulation is a way for a digital pin to simulate variable output power by switching on and off very quickly. It matters for controlling things like LED brightness, motor speed, or servo-style signals from a microcontroller pin.

SDA/SCL

SDA and SCL are the two signal lines used by an I2C bus: data and clock. Seeing these names helps you identify the correct connections when wiring I2C devices, even though Qwiic cables usually hide that wiring for you.

SRAM

Fast temporary memory used by a processor while a program is running. More SRAM helps with projects that handle larger data buffers, networking, displays, or more complex code.