The 9 pin DB9 connector serial port on a PC is commonly called which standard?

The 9 pin DB9 connector is commonly associated with the RS232 standard, which is a standard for serial communication. RS232 is designed for short-distance, point-to-point communication and has been widely used for connecting peripherals such as modems, printers, and other serial devices to computers. The DB9 connector is specifically designed to support this standard, making it a familiar sight on older computer systems for connecting devices.

The RS232 standard defines the electrical characteristics and timing of signals as well as the physical size and pinout of the connectors. It supports a standard voltage level of +/- 12 volts for signal transmission, which works well in environments where reliability and robustness were critical — a common requirement in data communication.

In contrast, USB, parallel, and Ethernet are different standards serving various communication needs. USB (Universal Serial Bus) is a more modern connection standard that supports higher data rates and more functionalities than RS232. Parallel connections are used for data transmission that occurs simultaneously across multiple channels, typically seen with printers and older peripherals. Ethernet, on the other hand, is a networking standard used primarily for local area networks (LANs) and does not utilize a DB9 connector but rather RJ45 connectors.

Thus, the correct identification of the DB9 connector