Design And Implementation Of External Interface Of Intelligent Instrument

The development of computer science and microelectronics causes tremendous impact and revolutionary influence to traditional measurements and instruments. With the further development of the microprocessor in small, powerful function, low price direction, and closer connection between measurement technology and computer technology, communication technology and automation technology, intelligent instrument with the function of computation, memory, automatic operation and communication function had come out. The intellectualize of the instrument has a higher standard on the communication between the instrument and the outside world, mainly reflected in higher communication rate, more powerful anti-jamming, easier use, easier network construction and etc. Therefore, the development of the external interface of intelligent instrument has a very strong significance for the intellectualize of the intelligent instrument.Langmuir probe automatic measuring instrument is an intelligent instrument which is mainly used to measure the plasma parameters. As the Langmuir probe automatic measuring instrument for application background, in this paper, we designed and implemented USB, Ethernet and Bluetooth interface on the bases of serial port communication. And so the performance of the instrument had been promoted and much easier to use. At the same time, this paper has also provided a universal method for developing external interface of intelligent instrument.The external interface of intelligent devices involved in this paper include USB, Ethernet and Bluetooth. The implementation of USB interface mainly include the USB hardware circuit design which based on LPC2148 microprocessor, USB firmware program design, USB driver design in Windows environment and application design. The implementation of Ethernet interface used AT91RM9200 microprocessor hardware structure, compiled and transplanted Linux 2.6 kernel, and also included network driver and network communication application. The design of Bluetooth communication introduce AT91RM9200 microprocessor and GC-232 Bluetooth module, completed the software and hardware design of Bluetooth interface.Besides the implementation of those communication interface, we also make a simple comparison for serial, USB, Ethernet and Bluetooth communication interface. In addition to this, we also designed a suit of communication protocol between host and device which is suitable for langmuir probe automatic measuring instrument.