The Design of Data Acquisition System Based on DSP
Abstract
With the rapid development of computer and information technology, Digital
signal processing technology has been more and mole important in high-speed and
real-time processing.It is widely used in graph and image processing, voice
identification,intelligent checking,industry control and other fields.A lot of rea-
timedata acquisition and processing systems choose DSP(Difital Signal Processor)as
hiscore processor,which ask for dealing with the collecting image data fast.In this
paper,we proposed a high-speed data collection system based on the digital signal
processing.We solved a lor of technology problems and difficulties in the system
design and implement way of all kinds of function units is also introduced and
analyzed in this paper.
The data acquisition and processing system completes acquisition and processing
to the analog signals and control of the machine using the chip of TMS320F2812.As
this chip has abundant of peripheral,we can have a simple circuit architecture,a
lowcost and a short development time by using it.We choose USB(Universal Serial
Bus) as the communication interface of DSP and the computer which can fulfill up
datatransfer and the control to DSP.The acquisitioned and processed data is
transferred to PC through the USB and dealed with by the top software.
According to the system’s need,we choose the analog to digital unit inside DSP
asthe system’s through the compare of two design themes,which is proved to meet
theneed of the system totally through the results of tests.Some methods are also
bringedforward to improve to the precision of the internal A/D converter and remove
theelectric disturb.Furthermore,we use simultaneous sampling mode and
cascadedsequencer mode to improve the acquisition and convert speed.
As for the order of electrifying for core professor-TMS320F2812,it’s CPU is
electrified earlier than the I/O peripherals which is different from others.Aiming at
thisproblem,a power supply design method has been brought forward,which solves
theorder of electrifying.For the large amount of image data that requires to be
processed,the inter memory resources of F2812 can’t meet the demand.As for this
point,this theme extends the outside memory according to the internal memory
characters of the DSP chip.
In addition,this theme gives the flow chart of the main program and the detail
methods about the system’s software design and implement,including system’s
initialization,data acquisition,analog to digital converter unit,data processing,data
communication and code optimization.The development flow of USB firmware is also
introduced in this theme.
Key words DSP;data acquisition;USB
