The advantage of using the asynchronous method is that no synchronization is required between the transmitter and receiver devices. It is also a more cost effective method. A disadvantage is that data transmission can be slower, but this is not always the case.

Definition Data Transmission: When we enter data into the via keyboard, each keyed element is encoded by the electronics within the keyboard into an equivalent binary coded pattern, using one of the standard coding schemes that are used for the interchange of. To represent all characters of the keyboard, a unique pattern of 7 or 8 bits in size is used.

The use of 7 bits means that 128 different elements can be represented, while 8 bits can represent 256 elements. A similar procedure is followed at the receiver that decodes every received binary pattern into the corresponding character. The most widely used codes that have been adopted for this function are the Extended Binary Coded Decimal (EBCDIC) and the American Standard Code for Information Interchange codes (ASCII).

Both coding schemes cater to all the normal alphabetic, numeric, and punctuation characters, collectively referred to as printable characters and a range of additional control characters, known as non-printable characters. Data transmission refers to the movement of data in form of bits between two or more digital devices. This transfer of data takes place via some form of transmission media (for example, coaxial cable, fiber optics etc.) Types of Data Transmission Parallel transmission Defination: Within a computing or communication device, the distances between different subunits are too short.

Thus, it is normal practice to transfer data between subunits using a separate wire to carry each bit of data. Download film one piece 3gp sub indonesia. There are multiple wires connecting each sub-unit and data is exchanged using a parallel transfer mode.

This mode of operation results in minimal delays in transferring each word. • In parallel transmission, all the bits of data are transmitted simultaneously on separate communication lines. • In order to transmit n bits, n wires or lines are used. Thus each bit has its own line. • All n bits of one group are transmitted with each clock pulse from one device to another i.e.

Multiple bits are sent with each clock pulse. • Parallel transmission is used for short distance communication. • As shown in the fig, eight separate wires are used to transmit 8 bit data from sender to receiver.

Advantage of parallel transmission It is speedy way of transmitting data as multiple bits are transmitted simultaneously with a single clock pulse. Disadvantage of parallel transmission It is costly method of data transmission as it requires n lines to transmit n bits at the same time.

Serial Transmission Defination: When transferring data between two physically separate devices, especially if the separation is more than a few kilometers, for reasons of cost, it is more economical to use a single pair of lines. Data is transmitted as a single bit at a time using a fixed time interval for each bit. This mode of transmission is known as bit-serial transmission. • In serial transmission, the various bits of data are transmitted serially one after the other. • It requires only one communication line rather than n lines to transmit data from sender to receiver. • Thus all the bits of data are transmitted on single line in serial fashion.

• In serial transmission, only single bit is sent with each clock pulse. • As shown in fig., suppose an 8-bit data 11001010 is to be sent from source to destination. Then least significant bit (LSB) i,e. 0 will be transmitted first followed by other bits. The most significant bit (MSB) i.e. 1 will be transmitted in the end via single communication line. • The internal circuitry of computer transmits data in parallel fashion.