Vxi Bus Graphics I / O Module Design

The virtual instrument is a combination of modern computer science and instrument science, it's also an important part in computer aided test. As the excellent representation of virtual instrument, the VXI bus is quickly growing and its application widely ranges from test and measurement to industrial automation.The digital I/O module is very important because of its data input and output function. But with the high demand of ATS on higher speed, data/pattern storage, data/pattern display and data/pattern edit, the project of pattern I/O module with 32 channels based on digital I/O module have been finished. The pattern I/O module can provide signal resource by software panel and transfer data by high speed. Besides, the module can also acquire, analyse external data and display the data on the software panel.This dissertation grounds on the development of pattern I/O module, some key techniques including the design of a register_based interface circuit and the data generating and sampling circuit are discussed explicitly. On the basis of Virtual Instrument Software Architecture, the programme of the instrument driver and Application software are discussed detailedly. And some idea and experience developed by the author in the course of debugging and testing the circuit are discussed also. As can be seen from actual test and application, the pattern I/O module is designed reasonally and satisfies all the performance.