Computer Science: Universal Serial Bus (USB)

Universal Serial Bus (USB)

• Form of serial data transmission.

• Most common input/output port for computers.

• Standardizes data transfer between devices and computers.

• Supports half-duplex and full-duplex communication.

USB Cable Configuration

• Red: +5V

• White: Data +

• Green: Data -

• Black: Ground

Benefits vs Drawbacks

Benefits

• Automatic detection and loading of device drivers.

• Connections fit one way, preventing incorrect connections.

• Industry standard with significant support.

• Supports transmission rates from 1.5 Mbps to 5 Gbps.

• Supplies +5V power through cables.

• Error notification for re-transmission ensures data integrity.

• Easy to add additional ports via hubs.

• Backward compatibility with older versions.

Drawbacks

• Maximum cable length of 5m without hubs.

• Early standards (V1) may not be supported by new devices.

• Data transfer rates are slower than Ethernet connections.

USB-C Characteristics

• 24-pin symmetrical connector, fits either way.

• Smaller than older USB versions; supports 100W (20V) power.

• Data transfer rate of 10 Gbps; backward compatible with USB 2.0 and 3.0 using adapters.

Connection Process

• Automatic detection of devices via voltage change in data signal.

• Appropriate drivers are loaded for communication.

USB Standards and Versions

• USB 1.0: 12 Mbps

• USB 2.0: 480 Mbps

• USB 3.2: Up to 20 Gbps

Connector Types

• Type A, Type B, Type C, Mini A, Mini B, Micro A, Micro B

• Backward compatibility across many connectors, e.g., Type-C supports USB 1.0 speeds.

Future Regulations

• By 2024, USB-C to be adopted as the common charger in the EU for small electronics.