Design And Implementation Of Multiple Interfaces Program-controlled Module For Intelligent Instrument Based On Sopc

Intelligent instrument is a product of the applications of computer technology. Great revolutionary changes have been taken place since it is started. Its core theme is small, intelligent, program-controlled and net-worked. At present, with the development of semiconductor technology, communications technology and large scale integrated circuits, intelligent instrument system design and methods have taken place great revolutionary changes. The novel embedded intelligent instrument system adopts the new embedded computing, controls and communications technology. Especially when FPGA emerges, it provides a new solution in intelligent instrument system design.Adopting embedded SOPC thought can solve the traditional design methods, which were of the lower integration, the lower robust functionality, the lower flexibility. This paper designed a function-cutted, general, easily portable intelligent instrument program-controlled module, which is based on the NiosⅡsoft-core CPU and involves embedded interfaces of Ethernet, RS232 and USB.As for the main body, this paper introduces the development process and trend of intelligent instrument, the definition of SOPC system and the related development environment based on hardware and software co-design. Then, it states the overall design scheme of various interfaces program-controlled intelligent instrument based on SOPC. From the start of multiple interfaces chip DM9000A's and ISP1362's function and controlling methods, in combination of its communication LwIP protocol, USB protocol, this paper implemented the development and communication of embedded Ethernet and USB device controller based on NiosII soft-core processor. Considering of the advantage of UART IP, RS232 serial communication was also implemented finally. In view of the multi-connection system characteristics, and according to the features of real-time operating systemμC/OS-Ⅱ, this paper designed and has implemented multi-connection communication unified scheduler module, the initialization of the every interface and call of communication protocol stack are taken task as the smallest unit, running reasonably as either parallel or serial, blurring the distinction between the physical interface, so as to unified in the same logical level. This paper introduces the layout and characters of programmable instrument standard command and implements the system program-controlling SCPI commands interpreter module.It is worth mentioning that we transplanted a read-only file system in system. It is used to store SCPI commands set. Interpreter generating module generates SCPI commands tree through reading SCPI commands set, making no relation between SCPI commands and interpreting program which can lead to the generation and cutting of system commands.This paper also implemented all the modules on DE2 development board. Experimental results show that all the modules works well, completes the tasks of communication, the SCPI interpreter completes the task of SCPI commands interpretering and locates the function number of related commands and implements the commands custom-cutting. This function-cutted, general program-controlled platform solution is well worth further studying and has a good application prospective and economic value.