Research On Extensible Technology Of MC8051 Soft Core For Internet Of Things Nodes

In recent years,the Internet of Things(IoT)technology has been gradually promoted and the embedded equipment has been developed and upgraded,which makes the application of IoT technology in people's production and life increasingly widespread.The number of sensor and communication device is also growing in practical applications.However,most of traditional IoT nodes use commercial processors,which have limited peripheral resources,and cannot effectively connect multiple devices in time.Connecting multiple devices with commercial processors can often make the system unstable and consume more system resources,it will increase the complexity and extend the development cycle of the IoT system development at the same time.System on Chip(SoC)integrates all system designs into one chip,which has a fast rate,strong extensibility and high integration.SoC is the focus of integrated circuit technology in the 21 st century.IP(Intellectual Property)core design is the key research object in SoC design method,and it plays an important role in the IoT development.In order to solve the above problem,this paper combines SoC technology and takes MC8051 soft core as the research object to research and design the extension technology for IoT nodes.The main work in this paper includes:(1)This paper analyzes the problems existing in the development of IoT nodes,and reviews the research status of IoT acquisition nodes and gateway nodes interface extension technology,and proposes the research of interface extension technology for IoT nodes based on SoC technology.The MC8051 soft core is selected as the research object for the extension technology by analyzing its architecture,hierarchical structure and functional characteristics and summarizing the features of the MC8051 soft core.(2)The general purpose I/O(Input/Output)is the main interface between the IoT acquisition node and the sensor device.Aiming at the problem that the number of general purpose I/Os of traditional commercial processors is limited and reused,the design method of the general purpose I/O in MC8051 soft core is analyzed.The general purpose I/O of the IoT acquisition node is effectively extended by declaring one-way data interfaces,configuring storage spaces and controlling registers based on the existing I/Os of the MC8051 soft core.(3)The serial communication interface is often used as the interface for the IoT gateway node to connect to the communication device.In view of the problems existing in the serial port extension method provided by the MC8051 soft core,this paper proposes an instant interrupt multi-serial port extension mechanism,and extends the special function register(SFR)designed for users to query the interrupt serial port unit.This paper uses the flexibility of the Field Programmable Gate Array(FPGA)to increase the system clock frequency to enhance the data transmission throughput of gateway nodes.The extended general purpose I/O port and the proposed instant interrupt multi-serial port extension mechanism are simulated and verified on the Modelsim software.The functional verification of the proposed extension technology is carried out on the experiment platform designed on the FPGA development board.The experimental results show that the proposed extension technology can achieve the expected functions and complete the data transmission effectively.At last,the proposed extension technology is applied in the actual development of internet of ships.This paper designs the minimum system board for the internet of ships gateway,and use it to connect the communication equipment to realize the effective communication of the navigation ship,the host computer and the shore-based dispatch center in the internet of ships application.This paper takes the MC8051 soft core as the research object,and implements the rapid extension of the general purpose I/O and the serial communication interface,and provides a solution for the problem of throughput reduction caused by multi-serial data transmission.The research on the extension technology based on soft core solves the problems brought by the development of IoT nodes using commercial processors,and provides a flexible and stable development platform for the customized design of IoT nodes.