RS232 is a standard serial communication interface used to transfer data between computers and other devices. It was originally developed by the Institute of Electrical and Electronics Engineers (IEEE) and later standardized as a standard in EIA (now TIA). The following is the principle of RS232 serial communication:
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RS232 serial communication adopts asynchronous communication mode, that is, when data transmission does not need a clock signal to synchronize the beats of both sides, but through some special characters of the sender and receiver to achieve data synchronization and transmission.
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In RS232 communication, data is transmitted in bytes, each byte consisting of 8 bits of binary digits, including a start bit, 8 data bits, and one or more stop bits. The start bit is usually a logical \"0\
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Before sending the data, the sender sends a handshake signal asking the receiver if they are ready to receive the data. The receiver replies with a confirmation signal, and the sender starts sending data.
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When receiving data, the receiver waits for a start bit, then receives eight data bits and one or more stop bits, and finally returns a confirmation signal. If the received data is incorrect, the receiver sends an error signal requesting resend.
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In order to improve the reliability and stability of communication, RS232 communication also supports two ways of data flow control and hardware flow control, which are used to ensure the stability and reliability of data transmission. Data flow control means that before data transmission, the sender sends a control signal to inform the receiver whether the data can be received. Hardware flow control is to control the transmission of data through some special pins in the RS232 interface (such as RTS, CTS, etc.) to ensure the stability and reliability of data transmission.
The principle of RS232 serial communication is that the sender uses the corresponding function to send code, and the receiver uses the corresponding function to parse the code and perform the corresponding operation.
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On the PC, RS232 serial communication is generally achieved by the control terminal or other devices. The specific steps are:
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1. Connect the RS232 serial port to the computer.
2. Then install the required drivers so that the operating system can recognize and use the serial port.
3. Next, use the \"system\" function on the command line to start the operating system.
4. In the operating system, use tools such as the serial debugging Assistant to establish a connection with the computer.
5. Then use specific commands to send and receive data.