Serial interface is abbreviated as serial port, also known as serial communication interface (usually refers to COM interface), which is an expansion interface using serial communication. In serial communication, data is transmitted one by one in sequence, and two-way communication can be achieved with just one pair of transmission lines. This is different from the parallel port, which transmits multiple bits of data at the same time. Because of its advantage of simple communication lines, serial ports are commonly used in communication between computers and other electronic devices, which greatly reduces costs and is particularly suitable for long-distance communication. The communication distance can range from a few meters to several kilometers. The disadvantage is that the transmission speed is slow.
Common serial port standards include RS-232, RS-485, and TTL serial ports. RS-232 is the most common serial port communication standard and is widely used in the connection between computers and peripheral devices. The maximum transmission distance of RS-232 is generally 15 meters, and the transmission speed can be adjusted according to demand. RS-485 is often used in industrial control systems and has stronger anti-interference ability and longer transmission distance (up to 1200 meters). RS-485 supports multi-point communication, and TTL (Transistor-Transistor Logic) serial ports use low-voltage signals (such as 3.3V or 5V) for communication, and are often used in embedded systems and microcontrollers to connect with other devices.
Advantages of serial ports
As a traditional and reliable communication method, the serial port has a relatively simple communication protocol, low hardware requirements, and stable and reliable transmission. It can be remotely controlled, especially in the form of RS-485 and TTL, the serial port can realize remote communication, which is very suitable for industrial automation, equipment monitoring and other occasions. In addition, the hardware implementation of the serial port interface is simple and low-cost, suitable for large-scale applications.
Application scenarios of serial ports
As a computer connected to external devices, such as printers, modems, mice, POS systems, etc. In industrial control systems, serial ports are widely used because they can maintain stable communication in harsh environments. In addition, in embedded systems, serial ports are of great significance for programming, debugging and testing embedded devices. In some scenarios where long-distance data transmission is required, serial ports can be used for remote control and data acquisition for remote diagnosis and troubleshooting.
