Adafruit Bluefruit LE SPI Friend - Bluetooth Low Energy (BLE)

Jargon buster

Plain-language definitions for the technical terms used above.

AT command set

An AT command set is a text-based control language sent over a serial terminal to configure a device. It matters because you can change settings such as baud rate and flow control without writing custom firmware.

baud

Baud is the signalling rate of a serial connection, often used as the speed setting for UART communication. Matching the baud rate matters because both connected devices must use the same setting for readable data.

BLE

BLE stands for Bluetooth Low Energy, a Bluetooth mode designed for lower power use and modern phone compatibility. It matters because BLE support can make the module easier to use with Apple devices and battery-powered projects, though it may behave differently from classic serial Bluetooth.

CS

CS stands for chip select, a control pin used by SPI devices to tell which connected device should listen. It matters when you connect more than one SPI module to the same microcontroller, because each device usually needs its own CS pin.

GPIO

General-purpose input/output pins are microcontroller pins you can set in software to read signals, switch devices on and off, or connect to peripherals. The number of GPIO pins matters because it limits how many buttons, LEDs, sensors, and other parts you can wire directly to the board.

HID

Human Interface Device is a USB device class used for keyboards, mice, gamepads and similar controls. If a board supports HID over USB, it can act like an input device to a computer without needing a custom driver.

microcontroller

A microcontroller is a small computer on a chip that runs your program and controls connected inputs and outputs. For this product, it is the part that reads buttons and sensors, drives the display and speaker, and communicates over Bluetooth.

OTA

OTA means over-the-air updating, where firmware is updated wirelessly instead of through a programming cable. It matters because you may be able to update or maintain the module after it is installed in a project.

Shield

An add-on board that plugs into a main controller board to give it extra features such as sensing, motor control or communication. Knowing a product supports shields helps you judge whether it can connect neatly into an existing maker-board setup.

SPI

A fast serial communication bus often used for displays, memory cards, and sensors. It matters because SPI devices need specific pins for clock and data, plus a separate chip-select line for each device.

UART

UART is a simple serial connection that sends data over separate transmit and receive wires, often labelled TX and RX. It matters because this module is designed to replace a wired UART cable with a wireless link while keeping the same serial data format.