DESIGN OF DATA ACQUISTION EQUIPMENT BASED ON USB
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Transcript of DESIGN OF DATA ACQUISTION EQUIPMENT BASED ON USB
DESIGN OF DATA ACQUISTION EQUIPMENT BASED ON USB
RAJESH.B
1KS07TE034
TELECOMMUNICATION
2
Introduction
USB CHIP DESCRIPTION
HARDWARE DESIGN
SOFTWARE DESIGN
CONCLUSION
USB PROTOCOL FEATURES
o Single connector typeo Hot-swappableo Plug and Playo High performanceo Expandabilityo Power supplied from the buso Easy to use for end usero Low-cost implementation Power pairPower pair
Differential Signal pairDifferential Signal pair
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INTRODUCTION
USB CHIP DESCRIPTION
HARDWARE DESIGN
SOFTWARE DESIGN
CONCLUSION
USB CHIP DESCRIPTION FX2 GENERAL VIEW
CY7C68013A
FX2 GENERAL ARCHITECTURE
FUNCTIONAL OVERVIEW OF THE BLOCK DIAGRAM USB Signaling Speed 8051 Microprocessor 8051 Clock Frequency USARTS Special Function Registers I2C-compatible Bus Buses USB Boot Methods
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Introduction
USB CHIP DESCRIPTION
HARDWARE DESIGN
SOFTWARE DESIGN
CONCLUSION
HARDWARE DESIGN
Master computer Detected Equipment
The master computer connects to the USB interface chip by USB electric cable then extends function circuit according to the interface circuit
CY7C68013A is used as the master control chip.
USB INTERFACE CIRCUIT
EEPROM DOWNLOAD CIRCUITThe Cypress EZ-USB family contains a general-purpose I2C interface through which the 8051 accesses standard I2C devices connected to the SCL and SDA pins.
FUNCTION CIRCUIT DESIGNMAX 197
The MAX197,a multi-range ADC, uses internal input
track/hold (T/H) circuitry to convert an analog signal to a 12-
bit digital output.
Input data and output data are multiplexed on a three state parallel interface.This parallel i/o can easily be interfaced with microprocessor.
CS,WR,RD control the write and read operations.CS is a
standard chip select signal which enables mp to address
MAX197 as an i/o port.
DATA ACQUISTION PROCESS IN MAX197
They are divided into two parts Internal acquition mode External acquistion mode The ACQMOD bit in the input control byte offers two
options for acquiring the signal: internal or external. Internal acquistion mode:
Select internal acquisition mode by writing the control byte
with the ACQMOD bit cleared (ACQMOD = 0). External acquistion mode:
The first pulse, written with ACQMOD = 1,starts an external
acquisition interval.
POWER DOWN MODES IN MAX197 To save power, you can put the converter into low
current shutdown mode between conversions.
Software power down : For software power down methods, STBYPD or FULLPD
is selected by programming PD0 and PD1 in the input control byte.
Hardware power down: For hardware-controlled (FULLPD) power-down, pull
the SHDN pin low.
Auto-Shutdown:
Selecting STBYPD on every conversion automatically shuts
the MAX197 down after each conversion.
SAMPLE AND HOLD CIRCUIT
The function of the sample-holding circuit is to provide invariable signals for MAX197 in the process of the analog-digital conversion
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HARDWARE DESIGN
SOFTWARE DESIGN
Introduction
USB CHIP DESCRIPTION
CONCLUSION
SOFTWARE DESIGN PC application software• Building communication between PC and data-
acquisition system• Sending control command and driver message
to the data-acquisition system• Receiving the state message and test result• Controlling test process• Displaying and analyzing the test result Firmware programFirmware is the solid program in the CPU. This system uses KEIL C as the development circumstance. Drive program• Driver files (*.sys) and a INF file (*.inf) are
downloaded
APPLICATIONS DSL modems ATA interface Memory card readers Cameras Scanners Home PNA Wireless LAN MP3 players
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HARDWARE DESIGN
SOFTWARE DESIGNARE DESIGN
Introduction
USB CHIP DESCRIPTION
CONCLUSION
CONCLUSION A design of data-acquisition equipment based
on USB is introduced. And this equipment has
been used to detect one industrial-control system.
The data of experiment indicates that this
equipment has high stability and high precision. Various indexes meet the designing request, and it can
be used in the electrical measurement and testing area widely.
THANK YOU FOR YOUR PATIENT LISTENING
QUESTIONS????