Seminar Topics & Project Ideas On Computer Science Electronics Electrical Mechanical Engineering Civil MBA Medicine Nursing Science Physics Mathematics Chemistry ppt pdf doc presentation downloads and Abstract

PRESENTED BY:
HARSHIT MEHROTRA

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Uart
 UART stands for Universal Asynchronous
Receiver/Transmitter.
 A UART may be used when:
 High speed is not required
 An inexpensive communication link between two devices is required
 UART communication is very cheap
 Single wire for each direction (plus ground wire)
 Asynchronous because no clock signal is transmitted
 Relatively simple hardware
PC devices such as mice and modems used to often use UARTs for communication to the PC
UART FUNCTIONS
 Transmitter
 Convert from parallel to serial
 Add start and stop delineators (bits)
 Add parity bit
 Receiver
 Convert from serial to parallel
 Remove start and stop delineators (bits)
 Check and remove parity bit
 SERIAL DATA TRANSMISSION
TRANSMITTER OPERATION
 Microcontroller waits until TDRE = '1'
 Loads data into TDR
 Clears TDRE
 UART transfers data from TDR to TSR
 Sets TDRE
 UART outputs start bit ('0') then shifts TSR right eight times followed by a stop bit ('1')
RECEIVER OPERATION
 UART waits for start bit
◦ Shifts bits into RSR
 When all data bits and stop bit are received
◦ RSR loaded into RDR
◦ Set RDRF
 Microcontroller waits until RDRF is set
◦ Read RDR
◦ Clear RDRF