What is a DB9 Serial Port?
1. The DB9 serial port is a standardized interface commonly used in the early days of serial communication.
2. Serial communication was the main means for computers to communicate with the outside world in the early days. Computers at that time had standard serial ports to communicate with the outside world. At that time, a set of standard serial port protocols was defined, and the DB9 interface was the standard interface.
3. There are 9 communication lines in the DB9 serial port, 3 of which are very important and are essential for GND, Tx, and Rx; the remaining 6 are related to flow control. In modern times, we use serial ports for debugging. Flow control is generally disabled, so these 6 are useless.
4. Nowadays, when using serial ports, you must remember to disable flow control; otherwise, unexpected problems may occur.
What is a serial port?
The serial port 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. The serial port is used to link serial lines to achieve serial communication. Common serial communication methods in life include serial servers. Serial port data can be transparently transmitted to Ethernet devices. The serial port 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.
