Some Windows CE–based devices can communicate with other computers, printers, modems, or Global Positioning System (GPS) satellites by way of a serial connection.
Serial I/O is the simplest form of communication supported by Windows CE. It is used when a direct, one-to-one connection exists between two devices. Serial I/O can occur by way of various hardware connections; however, most Windows CE–based devices use serial cables or a PC Card device, such as a modem or infrared (IR) transceiver. Exchanging data by way of a serial cable is similar to reading from or writing to a file.
Windows CE supports standard Windows-based desktop functions for serial communications. These functions can be used to open, close, and manipulate serial ports, transmit and receive data, and manage the connection. Windows CE–based devices use point-to-point protocol (PPP) and Serial Line Internet Protocol (SLIP) for direct serial and dial-up connections.