Serial Port ???

Serial Port is a serial communication physical interface through which information transfers in or out one bit at a time (contrast parallel port).Throughout most of the history of personal computers, data transfer through serial ports connected the computer to devices such as terminals and various peripherals.

In modern personal computers the serial port has largely been replaced by USB and Firewire for connections to peripheral devices. Many modern personal computers do not have a serial port since this legacy port has been superseded for most uses. Serial ports are commonly still used in applications such as industrial automation systems, scientific analysis, shop till systems and some industrial and consumer products. Server computers may use a serial port as a control console for diagnostics. Network equipment (such as routers and switches) often use serial console for configuration. Serial ports are still used in these areas as they are simple, cheap and their console functions are highly standardized and widespread. A serial port requires very little supporting software from the host system.

Common applications for serial ports

• Computer terminal
• Dial-up modems
• Printers
• Networking (Macintosh AppleTalk at 230.4kbit/s)
• Serial Mice
• Older Joysticks
• GPS receivers (typically NMEA 0183 at 4800bit/s)
• Older GSM phones
• Satellite phones, low-speed satellite modems and other satellite based transceiver devices
• Microcontroller, EPROM and other programmers
• Bar code scanners and other point of sale devices
• LED and LCD text displays
• Homemade electronic devices
• Older digital cameras
• Test and measuring equipment such as digital multimeters and weighing systems
• Updating Firmware on various consumer devices.

Serial ports use two-level (binary) signaling, so the data rate in bits per second is equal to the symbol rate in bauds.