Full-duplex asynchronous serial communication method

Abstract

The invention relates to the field of communication, in particular to a full-duplex asynchronous serial communication method. The method comprises the following steps of the step 1, carrying out pre-communication on two microprocessors to carry out first clock detection, the step 2, initializing the two microprocessor in serial communication, storing data sent and received by the two microprocessors into a data storer and finishing the data transmission between the sent and received data and a transmitting register DXR of an McBSP and data transmission between the sent and received data and a receiving register DDR through a DMA channel, the step 3, sending data and packing characters to be sent into data formats received by serial communication when the data are sent, and the step 4, receiving the data and sampling and correcting the received data flow to carry out second clock detection. On the premise without increasing hardware cost, the full-duplex asynchronous serial communication method improves the work efficiency of a CPU, reduces clock skew between signals and enables serial communication to be more stable, efficient, low in cost and simple and easy to achieve.

Description

technical field [0001] The invention relates to the technical field of electrical communication, in particular to a full-duplex asynchronous serial communication method. Background technique [0002] With the wide application of multi-microcomputer systems and the popularization of computer network technology, the communication between microprocessors is becoming more and more important. There are two ways of communication, parallel communication and serial communication. In multi-microcomputer systems and modern measurement and control systems The exchange of information in the computer mostly adopts serial communication. [0003] At present, there are generally two ways to realize serial communication between two different microprocessors. One is that two microprocessors perform asynchronous serial communication through their respective CPUs and asynchronous serial ports; the other is to use an external serial port. Line communication chip, this method is relatively simpl...

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Problems solved by technology

[0003] At present, there are generally two ways to realize serial communication between two different microprocessors. One is that two microprocessors perform asynchronous serial communication through their respective CPUs and asynchronous serial ports; the other is to use an external serial port. Line communication chip, this method is relatively simple to program, but increases the hardware cost and design cost, so the first simple communication method has been widely used, but as the microprocessor handles more and more tasks, The speed is getting faster and faster. This simple asynchronous serial port communication requires CPU processing for each byte processing, which seriously affects the efficiency of the microprocessor. Moreover, the current microprocessor clocks are all high-speed clocks, crystal oscillators There are more or less errors, plus some other physical factors, such as the delay of the signal line and the drawing board, etc. After frequency division or frequency multiplication, the precise synchronization of serial communication cannot be guaranteed, which may easily cause errors in serial communication. Signal offset and clock offset have a cumulative effect, the consequence is that the sampling is confused, and more seriously, it will cause the system to crash

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