What is RS-232C EIA-232-D? An Easy-to-Understand Explanation of the Basic Concepts of Serial Communication
RS-232C (Recommended Standard 232) or EIA-232-D (Electronic Industries Alliance 232-D) is a standard protocol used for serial communication between computers and peripheral devices. It defines the electrical and mechanical characteristics of the interface and the signaling method for transmitting data. Originally developed by the Electronic Industries Association (EIA) in the 1960s, it has become a widely adopted standard for serial communication in various industries.
Serial Communication:
Serial communication is a method of transmitting data in a sequential manner, one bit at a time, over a single communication channel. Unlike parallel communication, where multiple bits are sent simultaneously on separate lines, serial communication uses a single data line for transmitting and receiving data.
Basic Concepts of RS-232C:
RS-232C standardizes the communication interface between a data terminal equipment (DTE) and a data communication equipment (DCE). The DTE could be a computer or a device such as a printer, while the DCE is typically a modem or a similar communication device.
Here are some key concepts related to RS-232C:
1. Physical Interface: RS-232C specifies the electrical voltage levels for transmitting and receiving data. It defines the use of ±3 to ±15 volts to represent high and low states, respectively. The communication is usually achieved through a 9-pin or 25-pin connector, with each pin serving a specific purpose like transmitting data, receiving data, or providing the ground reference.
2. Asynchronous Communication: RS-232C typically uses asynchronous communication, where data is transmitted in separate packets called frames. Each frame consists of a start bit, data bits (typically 7 or 8), an optional parity bit for error detection, and one or more stop bits. The start and stop bits define the boundaries of each frame and ensure synchronization between the sender and the receiver.
3. Flow Control: RS-232C supports different flow control methods to manage the flow of data between the DTE and DCE. The two commonly used methods are hardware flow control (using control lines like RTS and CTS) and software flow control (using special characters or XON/OFF signals).
4. Applications: RS-232C has been widely used for connecting devices such as modems, printers, barcode scanners, and industrial equipment to computers. While advancements in technology have led to the emergence of newer communication protocols, RS-232C still remains relevant in many industries and is often seen in legacy systems.
In conclusion, RS-232C EIA-232-D is a standard protocol for serial communication that defines the electrical and mechanical characteristics of the interface. Understanding RS-232C is essential when dealing with devices that rely on serial communication. Although newer protocols have gained popularity, RS-232C continues to play a significant role in various industries.
Reference Articles
Read also
[Google Chrome] The definitive solution for right-click translations that no longer come up.