1. SERIAL VS PARALLEL COMMUNICATION &
SYNCHRONOUS & ASYNCHRONOUS DATA
TRANSMISSION
SHRI RAMSWAROOP MEMORIAL UNIVERSITY
SUBMITTED TO:
Dr. Vaibhava Srivastava
SUBMITTED BY:
Name: Amit Kumar
Roll no.: 202310101150190
Group: CS(DS+AI) 47
2. OVERVIEW OF THE PRESENTATION
• Serial Communication
• Advantages & Disadvantage
• Parallel Communication
• Advantages & Disadvantage
• Difference Between Serial & Parallel
• Synchronous DataTransmission
• Advantages & Disadvantage
• Asynchronous DataTransmission
• Advantages & Disadvantage
3. SERIAL TRANSMISSION
• In Serial Transmission, the bits of a byte are serially transmitted
one after other.
• The shift register is used for serial transmission
• The byte to be transmitted is the first stored in a shift register.
• Then these bits are shifted from MSB to LSB bit by bit in
synchronization with the clock. Bits are shifted right by one by
one position per clock cycle.
• As an advantage only one wire is used in serial transmission
between the transmitter and the receiver.
5. • In simple transmissions, the computer can only send data. There is only one wire.
• If the data can be transmission and received, then it is a duplex transmission
• Duplex transmission can be half or full duplex depending on whether or not the data
transfer can be simultaneous
• If the communication is only one way at a time, it is half duplex
• If both sides can communicate at the same time, it is full duplex
• Full duplex requires two wire conductors for the data lines
MODES OF SERIAL COMMUNICATION
6. • Only one wire is required
• Reduction is cost due to less number of conductor wire
• It is the most used method for long distance data transfers
ADVANTAGES OF SERIALTRANSMISSION
7. • Since there is only one line of transmission therefore the speed of transmission is quite
slow
• If we have to increase the speed of data transfer then it is necessary to increase the
clock frequency. But there ia a limit of clock frequency.
DISADVANTAGES OF SERIALTRANSMISSION
8. Serial transmission has two categories:
1. Synchronous data transmission
2. Asynchronous data transmission
TYPES OF SERIALTRANSMISSION
9. • Synchronous events means events which happen at the same clock rate.
• Synchronous transmission is carried out under the control of a common master clock.
• Here the bits which are being transmitted as Synchronous to the same reference clock.
• The stream of bits is combined into bigger frames which may comprise more than one byte.
• Each byte is transmitted without gap between the next byte.
• No start and stop bits are used instead the bytes are transmitted as a block in a continuous
stream of bits.
SYNCHRONOUS TRANSMISSION
10. • The receivers operates at the same clock frequency as that of transmitted.
• The data is send in blocks ( we can call these blocks as frames or packets) spaced by
fixed time intervals.
• It is the duty of receiver to separate the bits send in group
• There is an inter block idle time which also is filled with idle characters.
• Ways to find the solution to the problem of error in transmission because of loss in
synchronization is to include re-Synchronization of the clock and use of check digit to
ensure the byte in correctly interpreted and received
SYNCHRONOUSTRANSMISSION
11. • The main advantage is speed.The speed of transmission is much higher than that
asynchronous transmission.
• This is due to the absence of gaps between the data units and absence of start stop bits.
• Timing errors are reduced due to synchronization.
ADVANTAGES OF SYNCHRONOUS TRANSMISSION
12. • The timing is very important.The accuracy of the received data is dependent entirely on
the ability of the receiver to count the received bits accurately.
• The transmitter and receiver have to operate at the same clock frequency.This requires
proper synchronization which makes the system complicated.
DISADVANTAGES OF SYNCHRONOUS TRANSMISSION
13. • It is called asynchronous because timing of the signal is not an issue.The information can
be send & received as par mutual agreement of the sender & receiver.
• Asynchronous transmission is at byte level only because transmission of bits is always
synchronized.
ASYNCHRONOUS DATA TRANSMISSION
14. • Asynchronous transmission is eased by two bits, namely start bit as ‘0’ & stop bit as ‘1’.
• We send ‘0’ bit to start the communication & ‘1’ bit to stop the transmission.
• There can be a time delay between communication of two bytes.
• Only one byte is send at a time.After a gap of time next byte is transmitted.
• The transmitter and receiver may function at different clock frequencies.
• Asynchronous transmission is mostly used by asynchronous modems.
ASYNCHRONOUS TRANSMISSION
15. • It is a flexible data transmission method.
• Synchronization between the transmitter and receiver is not necessary.
• It is possible to transmit signals from the sources having different bit rates.
• The transmission can commence as soon as the data byte to be transmitted becomes
available.
• This mode of transmission is easy to implement.
• It is an effective scheme.
ADVANTAGES OF ASYNCHRONOUSTRANSMISSION
16. • Additional bits called start and stop bits are required to be used.
• The timing error may take place because it is difficult to determine synchronicity.
• It has slower transmission rate.
DISADVANTAGES OF ASYNCHRONOUS TRANSMISSION
17. • In data transmission, parallel communication is a method of conveying multiple
binary digits (bits) simultaneously. It contrasts with serial communication, which
conveys only a single bit at a time; this distinction is one way of characterizing a
communications link.
PARALLEL COMMUNICATION
18. • It offers fast data communication between devices compare to serial interface.
ADVANTAGES OF PARALLEL TRANSMISSION
19. • It supports short distance communication between devices.This is due to crosstalk
between the parallel lines.
• It uses more wires compare to serial interface and hence it is costly and a bit complex to
implement.
DISADVANTAGES OF PARALLEL TRANSMISSION