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????