Three elements of communication protocol: 1. Communication interface standard, which is a hardware protocol for communication, providing mechanical hardware, electrical, and functional characteristics and procedures; 2. Communication format, parameters that are set uniformly by both parties ;3. Communication data format.
#The operating environment of this article: Windows 7 system, Dell G3 computer.
Three elements of communication protocol:
1. Communication interface standard
The communication interface standard is a hardware protocol for communication, providing Mechanical hardware, electrical, functional characteristics and procedures. At the same time, the connection method of the transmission medium and network interface and the method of sending and receiving data are defined. Among the serial data interface standards, the most commonly used are RS232, RS422 and RS485 serial interface standards.
2. Communication format
In serial asynchronous communication, the communicating parties must negotiate the communication data transmission method, transmitted data length, verification method and transmission rate. Unified settings can ensure correct communication between both parties. This parameter that is set uniformly by both parties is called the data communication format (or communication parameter).
For example: the number of data bits, the number of stop bits, the check method (with or without check, parity check, check number), baud rate
Three , Communication data format
The communication protocol must stipulate the transmission content of the information. For example, the structure of the transmitted data information frame, device address, function code, sent data verification method, error detection, character format in information transmission, etc. These data messages specify a data format called communication.
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