DB9 Female Connector For RS232/RS422/RS485

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.

PCB

A printed circuit board (PCB) is a board, usually rigid, with etched copper tracks that connect electronic components together without loose wiring. Components are mounted on the board and signals route between them through the copper layout.

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.

through-hole

A mounting style where the component leads pass through holes in a circuit board and are soldered on the other side. Through-hole parts are often easier to handle and solder by hand, which is useful for classroom and hobby projects.