Micro controller based DAQ
Upcoming SlideShare
Loading in...5
×
 

Micro controller based DAQ

on

  • 1,893 views

 

Statistics

Views

Total Views
1,893
Views on SlideShare
1,893
Embed Views
0

Actions

Likes
0
Downloads
80
Comments
0

0 Embeds 0

No embeds

Accessibility

Categories

Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

    Micro controller based DAQ Micro controller based DAQ Presentation Transcript

    • DATA ACQUISITION SYSTEM USING AT89C51 PREM KUMAR M-TECH (PED) REG NO-1611110018
    • INTRODUCTION The main objective of this project is to developthe data acquisition system. In this project AT89c51 isused to develop the data acquisition system
    • WHAT IS DAQ?  Data acquisition (DAQ) is the process of measuring an electrical or physical phenomenon such as voltage, current, temperature, pressure, or sound with a computer.  DAQ systems either measure a physical parameter or take a specific action (sound an alarm, turn on a light, etc.) based on the data received.
    • DAQ SYSTEM A DAQ system consists of sensors, DAQmeasurement hardware, and a computer withprogrammable software sensor DAQ DEVICE COMPUTER DRIVER
    • BLOCK EXPLANATION First the sensor measures the physical quantity or electrical quantity like temperature, pressure, voltage or current. DAQ device which converts measured analog signal into digital signal. And it is also interfaced with PC. We can control the driver circuit by computer through data acquisition system.
    • INTERFACING DIAGRAM
    • PIN DESCRIPTIONCONNECTEDTO ADC TOSELECTSENSORCONNECTEDTO DRIVERCIRCUIT CONNECTED TO MAX 232 CONNECTED TO ADC
    • ANALOG TO DIGITAL CONVERTER ADC 0808 is 8 bit analog to digital converter, which uses successive approximation type conversion. Key specifications:  Resolution 8 Bits  Total Unadjusted Error ±½ LSB and ±1 LSB  Single Supply 5 VDC  Conversion Time 100 μs
    • MAX 232 The RS232 is not compatible with 89c51,we need a voltage converter to convert the RS232’s signals to TTL voltage levels that will be acceptable to the 89c51’s TxD and RxD pins. The MAX232 converts from RS232 voltage levels to TTL voltage levels, and vice versa.one advantage of the MAX232 chip is that we can use same power supply(+5V) for controller and MAX232.
    • PROGRAM Start : MOV P1,#00H LCALL initserial LCALL latch LCALL start_conv LCALL wait LCALL get MOV A,P2 MOV R6,A LCALL send_read SJMP Start
    • PROGRAM CONT….delay :MOV R4,#80Hhere : MOV R5,#30Hagain : DJNZ R5,again DJNZ R4,here RETinitserial : MOV TMOD,#20H MOV TH1,#FDH MOV SCON,#50H SETB TR1 SETB EA SETB ES RET
    • PROGRAM CONT….start_conv : LCALL delay CLR P3.3 LCALL delay SETB P3.3 RETwait : JB P3.4,wait RETget : LCALL delay CLR P3.5 LCALL delay SETB P3.5 RET
    • PROGRAM CONT….send_char : MOV SBUF,R6next : JNB TI,next CLR TI RETsend_read : LCALL send_char MOV A,# “,” LCALL send_char RETlatch : CLR P3.6 LCALL delay SETB P3.6 RET
    • CONCLUSION Thus, the data acquisition system usingATMEL89c51 microcontroller and ADC0808 isdesigned. Also, proved it is more flexible as programcan be changed according to requirement repeatedly.