BlueSMiRF v2 Bluetooth Serial Link with JST-GH

Jargon buster

Plain-language definitions for the technical terms used above.

2.4GHz WiFi

2.4GHz WiFi is a common wireless networking band used by many routers and embedded devices, offering good range but more congestion than the 5GHz band. Devices on this band can join networks to transfer data or receive firmware updates.

5V-tolerant

5V-tolerant means an input pin can safely accept a 5V logic signal even if the device itself runs at a lower voltage such as 3.3V. Such inputs can be wired directly to 5V microcontroller boards with less risk of damage.

AP2112K

AP2112K is a small low-dropout (LDO) voltage regulator that supplies a stable fixed output (commonly 3.3V) from a higher input such as USB 5V. Its ratings matter for checking the acceptable input voltage range and the maximum current available to the powered electronics.

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 low power use and broad compatibility with modern phones and computers. It connects well to battery-powered and mobile devices, including Apple hardware, though it behaves differently from Bluetooth Classic and its serial-style profiles.

Bluetooth Classic SPP

Bluetooth Classic SPP, or Serial Port Profile, makes a Bluetooth connection behave like a traditional serial port. It matters because many Android devices and computers can use SPP to receive serial data without special hardware.

CTS

CTS stands for Clear To Send, a serial flow-control signal that tells the other device it may transmit. It matters for reliable high-speed serial communication where buffers could otherwise overflow.

ESP32

ESP32 is a family of low-cost microcontroller chips and modules from Espressif with built-in WiFi and Bluetooth. They support programmable firmware and over-the-air updates, and are commonly programmed with toolchains such as the Arduino core and ESP-IDF.

ESP32-PICO-MINI-02

ESP32-PICO-MINI-02 is a compact system-in-package wireless module from Espressif that integrates an ESP32 chip, flash and supporting components with a PCB antenna. The exact part number helps you check its datasheet for wireless capabilities, antenna type, pinout and long-term availability.

full-duplex

Full-duplex means data can be sent and received at the same time. It matters for interactive serial links where commands and responses may need to travel in both directions without taking turns.

GND

GND is the ground or reference connection (0 V) for a circuit. When connecting two devices together, their grounds must be joined so both agree on what counts as a low or high signal.

GNSS

GNSS stands for Global Navigation Satellite System, an umbrella term for satellite positioning networks such as GPS, GLONASS, Galileo and BeiDou. Receivers use these satellites to determine position, and high-precision units can output a steady stream of serial position data.

Headers

Rows of connector contacts on a fixed pitch (commonly 2.54 mm) used to link a board to a breadboard, jumper wires, or another board. They come as male pin headers and female socket headers; when a module ships with pre-soldered headers it can be used straight away, whereas bare pads require soldering the pins yourself.

JST-GH

JST-GH is a small locking connector family commonly used where vibration or compact wiring matters. Knowing the connector type helps you choose matching cables and check whether it will plug into your existing telemetry or GNSS hardware.

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.

logic-level shifting

Logic-level shifting converts digital signals between different voltage levels, such as 3.3V and 5V. It lets devices connect safely to microcontrollers and peripherals that use different logic voltages without damaging either side.

OTA

OTA means over-the-air updating, where a device's firmware is updated wirelessly rather than through a programming cable. This lets firmware be updated or maintained after a device is installed without a physical connection.

PCB antenna

A PCB antenna is an antenna pattern built directly into the circuit board rather than a separate metal antenna. It matters because placement, nearby metal and enclosure design can affect wireless range.

PTH

Plated through-hole means the pin holes are metal-lined so solder connects the pad on both sides of the board. It is useful for connectors and headers that need a strong mechanical and electrical connection.

RF

RF means radio frequency, referring to signals used for wireless communication and other high-frequency electronics. A low-noise, stable power supply is important for RF circuits because power noise can affect signal quality and measurements.

RS232-to-TTL

RS232-to-TTL conversion translates the higher, inverted voltages of classic RS232 serial ports into the low-voltage logic-level (TTL) serial used by microcontrollers. Connecting a true RS232 signal directly to a TTL input can damage it unless a converter is used.

RTS

RTS stands for Request To Send, a serial flow-control signal used to manage when a device is ready to receive data. It matters when moving fast serial streams because flow control can help prevent lost data.

RX

RX means receive, usually showing data being received by the board. An RX indicator LED can help with troubleshooting USB or serial communication.

Tolerance

Tolerance tells you how far the real resistance value may be from the printed value. A 1% resistor is useful when a circuit needs more predictable behaviour than a looser 5% or 10% part.

TX

TX means transmit, usually showing data being sent from the board. A TX indicator LED can help you see when the board is communicating or uploading code.

UART

UART is a simple asynchronous serial interface that sends data over separate transmit and receive wires, usually labelled TX and RX, with both ends set to the same baud rate. It is a common way for microcontrollers and other serial devices to exchange data.

VCC

VCC is the positive power-supply connection on a chip or module. Connecting it to the correct supply voltage is needed for the part to power on and helps avoid damaging the electronics.