Development Of CPCI Multifucntional Module

Multipart digital signal module is one of the general modules employed in autom ation-testing systems.It can test many types of input signals and generate an assortment of communication and drive signals on the system 's demand.Currently the multifunctional modules in the market are massively limited in terms of achievable functions,types of communication signals,as well as the variety,precision,and speed of measurement.This work endeavors to develop a CPCI multifu nctional module for an aerospace science and technology corporation while developing the supporting testing software.Our research entailed the hardware design,software design,and drive development of the module.The module developed is capable of automatic,high-precision and multi-project measurement of multichannel digital signals.Other functions include generating optical alignment signals,good alignment signals,and specific frequency pulses and controlling RS-422 communications.Applying the bus of mature CPCI industrial computers as system bus on a CPCI board of 3U standard size and using highly-integrated FGPA as control core,our module mainly integrated 26 measurement channels,6 RS-422 communication channels,a circuit unit of DAC-generated optical alignment signals,and 1 output channel for the good alignment signals in the drive external circuitry.A number of plans were prepared to make sure that each functional circuit works.With our original design of a wide-amplitude-modulation signal-preprocessing circuit with no need of switching circuits,we enforced effectual segregation among the measurement channels and between the simulated and digital circuits.In the aspect of hardware control,by constructing SOPC system on FGPA,logical compon ents of assorted multifunctional modules were designed through Verilog programming.Via the Avalon bus the interconnection between the processor and numerous IP modules was established in order to orchestrate data management mechanisms for multifarious communication resources.Specifically,to achieve measurement functions such as high-precision time intervals and frequencies,the method of synchronizing measurement gates with the edges of the to-be-measured signals was implemented along with proper data management methods.As for the various waveforms with configurable parameters required by optical alignment signals,we adopted the DDS technique to design the circuit of the D/A conversion sector and impel it to put out sine waves,square waves,and direct currents.For RS-422 communications,UART protocol was compiled to control signal transfer.The supporting software includes Nios II software and PC software.Firstly the application of Nios II software was designed to control the operation of SOPC.Subsequently the application and user interface of PC software were developed using Labwindows/CVI while the supporting lowest driver was developed by NI VISA.Meanwhile,another set of drivers was developed using Qt for the Neo Kylin operating system adopted by our module in the practical application environment.Results from the testing systems built to test the CPCI multifunctional module developed in this work indicate that it is able to run steadily and achieve intended functions,satisfying all precision requirements.Our module possesses both flexibility and portability,which give it not only practical application value in the design of miniaturized,flexible,and multifunctional modules,but also reference value in the relative field of integrated-circuit design.