Bluetooth-enabled Thermal Sensor

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Bluetooth-enabled Thermal Sensor

• 4 December, 2002
• Bonnie Benjamin
• Kavitha Sagi
• Shelly Wisted
• ECE 345 - Schreiber

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Presentation Overview

• Project Description
• Challenges
• Lessons Learned
• Questions
• Acknowledgements

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High-levelOverview
Circuit
Bluetooth
LabVIEW
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Circuit Detail
Temp Sensor
Adder
Amplifier
Rectifier
PIC16F877
Max 232
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Temp sensor

• LM34CH
• Sensor range
• -50 to 350F
• Range for project
• 68 to 105F
• 118 mV per F
• 8.44F per V

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Sensor Calibration
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Sensor Calibrationwith trendline
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Adder

• Input range
• -1 to 6 V
• Shifted range
• -1.72 to 5.28 V
• Purpose
• 0V 68F
• 0.356V 105F

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Amplifier

• Gain 12.5 V/V
• Amplified range
• -5 to 5 V
• Saturates at 5V (ideally)
• Purpose
• 0V 68F
• 4.3V 105F
• 0-5V range for PIC

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Rectifier
Rectifier
Inverter

• Gain 1 V/V
• New range
• 0 to 5 V (ideally)
• Purpose
• Acts like clipper (0 5 V)

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Circuit Performance
Calculated
Saturation point at 103
Measured
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PIC16F877

• RS232 Standard
• iSPA
• Data transmission
• A/D
• 10 bit conversion
• USART
• Start and Stop Bits
• Baud rate generator
• Fosc/(64(x1))

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PIC Programming

• Basic Programming
• L.E.T PicBasic Pro
• PICALL
• Testing
• A/D
• USART

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MAX 232

• RS 232 Standard
• Converts voltage
• Transmits bits to iSPA
• Data rate of 9600

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High-levelOverview
Bluetooth
Circuit
LabVIEW
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Bluetooth Detail
Impulsesoft Serial Port Adapter (iSPA) (from
circuit)
Belkin card (PCMCIA card) (on laptop)
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iSPA

• Acts as a COM port
• Configure
• Server
• Bits/sec, stop bits, flow control
• Testing Functionality
• Other Bluetooth Devices
• Data Transmission

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PCMCIA Card

• Client
• Configure as COM port
• Same baud rate and stop bits as iSPA
• Data Acquisition

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High-levelOverview
LabVIEW
Circuit
Bluetooth
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LabVIEW detail
COM port
Collect 8 bits
Convert to voltage
Convert to temperature
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LabVIEW D/A Conversion
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LabVIEW Final Program
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LabVIEW Final Program
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Challenges

• Little knowledge of concepts
• Bluetooth
• PIC programming
• RS232 standard
• Data acquisition from COM port
• Wide temperature range
• Ordering from International

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Lessons Learned

• General
• Bluetooth Standard
• LabVIEW
• Department Resources
• Relating with customer support
• Electrical
• Datasheet terminology
• Analog circuits
• Lab equipment

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Questions
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Acknowledgements

• Shaun Anders
• Dr. Jennifer Bernhard
• Christian Hahn
• Paul Leisher
• Dan Mast
• Henry Schaper
• Russ Schreiber
• Dr. Gary Swenson
• Jim Wehmer

• Belkin
• Impulsesoft
• Microchip
• National Instruments