PC COM ports, USB virtual COM ports, and ports in embedded systems are all addressed in this updated guide to programming, interfacing, and using serial ports. Topics include using .NET's SerialPort class for COM-port communications on PCs; upgrading existing RS-232 designs to USB or wireless networks; and creating serial networks of embedded systems and PCs. Example circuits and code provide a quick start to projects. Installation and maintenance staff will also find tips for ensuring reliable operation and problem tracking.