Arduino RS232 Shield

Jargon buster

Plain-language definitions for the technical terms used above.

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.

capacitance

Capacitance is the amount of electrical charge a capacitor can store, usually measured in farads such as uF. Choosing the right capacitance value matters because it affects how well a circuit filters power, handles timing, or stores short bursts of energy.

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.

I2C

I2C is a two-wire communication bus used by many sensors and small modules. It matters because several I2C devices can share the same two wires, but each device needs a compatible address and your controller must support I2C.

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.

RS-232

RS-232 is an older serial communication standard that uses higher, inverted signal voltages (typically around plus or minus 3 to 15 volts) rather than the low logic levels of modern microcontroller pins. When connecting RS-232 equipment to a microcontroller, you usually need an RS-232 transceiver or level converter rather than wiring it directly, or you risk damaging the pins.

RS485

RS485 is a robust differential serial communication standard often used in factories, farms and buildings where cables may be long or electrically noisy, and it can link many devices on a single pair of wires. When a product lists RS485, it can communicate with industrial sensors, meters and control equipment over longer distances than typical hobby serial wiring.

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.

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.