Data Connectors

Serial Communication Basics

In telecommunications, the process of sending data sequentially over a computer bus or communication cable is known as serial communication. Serial communication transmits data one bit at a time. Parallel communication transmits bits simultaneously over multiple communication lines in a single bus or cable. While it may seem that parallel communication would be the preferred method, this is not true in many situations. 

Because of the increased complexity and data transmission, serial communication has faster speeds than parallel communication. The speed at which serial is communicated can be altered by adjusting what is known as the BOD rate, which simply increases the number of the bits that can be transmitted per second. This is one of the reasons serial communication methods have remained such a common method for basic communication in much of computer based hardware used today. 

Some of the most common standards that have been created to take advantage of serial based communication in the industrial space would be RS 232 and RS 485. The earlier RS 232 standard was very common in computing in many different industrial, commercial and residential applications. It had lower transmission speeds, short maximum cable lengths and large voltage swings, making it useful only in certain situations. RS 485 is an improved standard that is still found in many of the same applications today. It resolved many of the issues the earlier RS 232 standard had by allowing longer cable lengths, higher transmission speeds and other improvements that increased its usability and performance.