Before USB ports became standard on PCs, several devices connected through a serial port. They're obsolete in many ways, but ...

[Mike Lu] likes to add serial ports to his routers to use ... signals and still have the option of using that port for a network connection. The first step was to build the circuit to output ...

His custom circuit board takes that sound in through the headphone jack and demodulates it for use on the serial port of a PC. This connection to controls a flight simulator using the G1‘s ...

A circuit board that contains multiple serial ports for connection to modems and other serial devices. The serial port is used as an interface by many different kinds of sensors and data ...