Introduction:
The Universal Asynchronous Receiver/Transmitter (UART) takes bytes of data and transmits the individual bits in a sequential fashion. At the destination; a second UART re-assembles the bits into complete bytes. Each UART contains a shift register, which is the fundamental method of conversion between serial and parallel forms. Serial transmission of digital information (bits) through a single wire or other medium is much more cost effective than parallel transmission through multiple wires
Overview:
Universal Asynchronous Receiver Transmitter (UART) is the heart of serial communication. Synchronous
communication requires a common clock which should have same phase and frequency for the entire duration of communication. But it is very difficult to maintain same clock frequency and phase for a longer time to all devices which are involved in serial communication. So to avoid this problem, asynchronous communication is used, which operates on different clocks where to check the order of communication extra synchronization bits are added. UART resides in computer and this computer can handle parallel data only. So in transmitter side, UART takes parallel data from computer and converts it in serial form and in receiver side, another UART takes this serial data from transmitter and converts back in parallel form so that computer can handle it.
The internal architecture of UART mainly consists of two modules, transmitter module and receiver module. FIFO, parallel to serial shift register, parity generator and multiplexer are the sub modules of UART transmitter. Same way UART receiver consists of serial to parallel shift register, parity detector and FIFO. FIFO is used for temporary data storage purpose.