Advantages And Disadvantages Of Serial And Parallel Data Transmission

Transmission rate Specifies the number of bits to send each second.The unit is bps (bits per second) and is selected from 300, 600, 1200, 2400, 4800, 9600, 19200, and so on.By matching the settings and timing, the data delimiters correspond, and data can be normally sent and received.For this reason, a start bit is added to each item of data (1 byte) to acquire the correct timing. In asynchronous communication, data is sent and received one bit at a time on one data line, so if each side's communication condition settings do not initially match, normal communication is not possible.Matching the computer (controller) side settings to the peripheral equipment side settings is the normal setup method. Asynchronous communication This method sends and receives data synchronized to each side's own self-generated clock.Normal communication is not possible if the transmission rate settings do not match.In other words, both the sending side and the receiving side initially agree on how many bits to transfer each second, and then each creates a synchronization signal of a frequency that matches that transmission rate. Synchronous communication This method sends and receives data synchronized to a clock generated by the other equipment or by a self-generated clock.Communication is performed is based on a synchronization signal added to each bit from the sending side.This has good data transmission efficiency but there is a demerit in that the transmission procedure becomes complicated. In serial communication, data is sent one bit at a time using one signal line, so in order for the receiving side to accurately receive the data, the sending side must know at what speed it is sending each bit.In RS-232C, synchronous communication and asynchronous communication standards have been defined.For peripheral equipment used for measurements or control, the previously mentioned full-duplex communication and asynchronous communication are typically used. Asynchronous communication and synchronous communication Half-duplex communication A method where communication is performed using one transmission line while switching between send and receive.For this reason, simultaneous communication cannot be performed.

Half-duplex communication and full-duplex communication Full-duplex communication A method where send and receive both have their own transmission line so data can be simultaneously sent and received.

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Advantages And Disadvantages Of Serial And Parallel Data Transmission