What is serial port parallel, serial port connection

2020-08-10 18:19: 13Zongheng Intelligent Control 4

Parallel and serial interfaces

(1) Serial and parallel mainly consider the number of communication lines, which is the amount of information that the sender and receiver can transmit at the same time.

(2). For example, in a level signal, 1 reference level line and 1 signal line can transmit 1 binary bit; if we have 3 lines (2 signal lines and 1 reference line), 2 binary bits can be sent at the same time. ; If you want to send 8 bits of binary at the same time, you need 9 lines.
(3) Under differential signals, 2 lines (different from each other) can send 1 binary bit at the same time; if you need to send 8 binary bits at the same time, 16 lines are needed.
Summary: It sounds like the parallel interface is faster than the serial interface (the serial interface can only send 1 binary bit at a time, while the parallel interface can send multiple binary bits at a time) and is better; but in fact the serial interface is the king, use is relatively wide. Because it saves signal lines, has lower requirements and lower costs for transmission lines; and when serial, the overall communication performance can be improved by increasing the communication speed, and it does not necessarily have to be parallel.

Summarize:

In fact, after so many years of development, the final winners are: asynchronous, serial, differential, such as USB and network communication.