Puerto serie
It is also called a serial port. Compared with the transmission speed of the parallel port, the transmission speed of the serial port is relatively low. Commonly used to connect controllers, security cameras, etc. It is used to link serial lines to achieve serial communication. Common serial communication methods in life such as serial servers. Serial port data can be transparently transmitted to Ethernet devices. It is usually a 9-pin D-type interface, which we usually call a DB-9 connector. A piece of data can be transferred to the other end. The DB-9 pin connector diagram is as follows.
Parallel Port
The parallel port can also be called a parallel port. Its transmission rate is faster than the serial port. The parallel port can move a group of 8 bits at a time on eight different lines and uses a 25-pin connector. This is why it is similar to serial communication. Faster than that. The parallel port is also called the DB-25 connector.
Commonly used in computers, hard drives, zip drives, CD-ROM drives, etc. Although the transfer speed is faster, all bit streams of the parallel port need to transfer data at the same speed in parallel communication. If the line is too long, it is impractical to meet this condition, so the transmission line should not be too long. The DB-25 pin connector diagram is shown below.
Comparison table of the differences
| Puerto serie | Parallel port |
| In its communication, less number of wires are used. | In its communication, more number of wires are used compared to serial port. |
| It is used to implement serial port transmission. | It is used to implement parallel transmission. |
| It is capable of passing a single stream of data. | It can pass multiple data streams simultaneously |
| The transmission speed of a serial port is relatively low compared to the transmission speed of a parallel port. | The transmission speed of a parallel port is higher than the transmission speed of a serial port. |
| It is commonly implemented in modems, connectivity devices, security cameras, and controllers. | It is commonly implemented in zip drives, printers, hard drives, CD-ROM drives, etc. |
| In serial ports, the public ports are involved. | When in a parallel port, refers to the mother port |
| It sends again and again. | It send multiple bits at a time. |
Data Transfer Protocol
The data transfer protocol plays a vital role in the communication between serial and parallel ports.
RS-232 is the most common serial communication protocol, which is widely used to connect computers to external devices. Due to its simplicity and ease of use, RS-232 is widely used in many legacy devices such as modems and printers. This protocol defines the electrical characteristics, signaling method, and data format, and usually transmits a voltage signal of plus or minus 12V, making it suitable for communication over short distances (usually no more than 15 meters).
RS-485, on the other hand, is more suitable for specific applications, especially in industrial automation and control systems.RS-485 uses differential signaling, which provides greater immunity to interference and enables reliable communication over longer distances, typically up to 1,200 meters. In addition, RS-485 supports multipoint communication, allowing up to 32 devices to be connected on the same bus, which makes it excellent in complex network topologies. Although RS-485 is very effective in some areas, its use is relatively narrow due to its complexity and specific application scenarios.
Another important protocol is IEEE 1284, a standard for parallel communication. It is primarily used for connections between computers and printers. It supports bi-directional data transfer, which allows data to flow in both directions simultaneously, thus increasing transmission efficiency. IEEE 1284 has a variety of transmission modes that can be adapted to the needs of different devices and is suitable for connecting external devices such as printers and scanners.
Conclusión
An in-depth analysis of serial and parallel ports allows us to more fully understand the importance of these technologies in modern computing and communications.
