Explain about RS 232 interface.

The RS 232 was widely used in 1960, and is currently most widely used communication protocol. It is simple, inexpensive to implement and relatively slow. It is more than simple serial communication devices such as keyboard and mice. RS 232 is a single ended data transmission system, which means that it uses the single wire for data transmission. Signals are proceeded by determining whether they are positive or negative when compared with a ground. Because signals travelling the single wire are vulnerable to degradation, RS 232 systems are recommended for communication over short distances (up to 50 feet) and relatively slow data rates (up to 20 kbps). However, in practice this limit can be exceeded.

A typical system is made up of two type of device, data communication equipment (DCE) and data termination equipment (DTE). Typically DTE is defined as the communication source, and DCE is defined as the device that provides a communication channel between two DTE type devices.

In order for DCE and DTE devices to communicate with each other, two wires must be used- one for transmission and other for reception and both device must not use the same wire for the same purpose.