Method for identifying frame address in asynchronous communication control

Abstract

The invention relates to the field of asynchronous communication of a universal asynchronous receiver / transmitter (URAT), in particular to a method for identifying a frame address in asynchronous communication control, comprising the following steps of: first receiving the first byte of an information frame by using the first byte of the information frame as address information; and receiving the information frame when judging whether the address information is as same as the address information of a computer or not. Through adopting the method, when the first byte of the transmitted information frame is the address, the automatic identification of the frame address can be realized. The information frame is received when the address of the information frame is as same as the address of the computer, the finish breakage is automatically generated after the reception of the information frame is finished, and then a Central Processing Unit (CPU) is notified that the reception of the information frame of the equipment is finished. In the communication (such as MODBUS-radio teletypewriter communication (RTC)) adopting the time to judge whether the frame is finished or not, a timer need not to be arranged in the CPU to judge whether the reception of the information frame is finished overtime or not so that the automatic identification function and the frame finish breakage control of eight-byte address hardware are realized, the URAT has good universality, and meanwhile, the running efficiency of the CPU is greatly enhanced.

Description

technical field [0001] The invention relates to the field of URAT asynchronous communication, in particular to a frame address identification method in asynchronous communication control. Background technique [0002] Common control chips for general asynchronous communication include 16C450, 16C550, 16C750, etc. 3-bit address bus, 8-bit address bus, read-write control bus and other interfaces can realize baud rate setting, stop bit number setting, data bit number setting, and various error reporting functions. The communication rate of the universal asynchronous communication control chip has reached several megabits per second, which can realize high-speed communication. [0003] Existing asynchronous communication is applied in a multi-machine communication network with RS485 interface, and the CPU of the slave device needs to judge whether it is the address of the device, and then determine whether to respond. In the communication with timeout as the end of the frame, ...

AI Technical Summary

Problems solved by technology

In the communication with timeout as the end of the frame, in order to judge whether to respond to the data frame, the CPU needs to set a timer to judge the end and start position of the frame, and judge whether the address of the information frame is the local address, and decide whether to give Response, so that the CPU is frequently interrupted, causing the efficiency of the slave device to be affected

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