Bio-Feedback Wristwatch Device for EH Children

1. Bio-Feedback Wristwatch Device for EH Children ECE University of Central Florida

2. Emotionally Handicapped Children Project Summary - Wrist-Watch Device For EH Children, 6-10 years old - Monitor Motion And Skin Temperature - Game System Is The Heart Of the Behavior-Redirection Program About EH Children - Unstable - Violent - Need Special Attention Goals - Redirect Violent Behavioral Patterns Through Distraction - Facilitate the withering away of neural pathways that lead to negative thinking

3. BLOCK DIAGRAM

4. Thermistors

5. Negative Temperature Coefficient (NTC) Thermistors Definition - Thermally Sensitive Resistor - Decrease In Resistance With Increase In Temperature Application - Medical devices - Machinery - Appliances - Computers

6. Negative Temperature Coefficient (NTC) Thermistors Advantages - Large Change In Resistance Vs Temperature - Fast Time Response - Small Size - High Stability And Accuracy Disadvantages - Non-Linear - Low Power Handling Capability

7. Resistance vs Temperature Table

9. Temperature Circuit Components Thermistor Circuit Dual Bifet Op Amp A/D Converter

10. Thermistor Circuit 10 k Thermistor In Series With 10 k Resistor And 5 V Supply Voltage Output to Thermistor is Connected to a Noninverting Amplifier

11. Bifet Op Amp TL082 Low Cost High Speed For Single or Dual-ended Power Supply Applications Input Voltage Range: �15V Gain Av = (1+400/1000) = 1.4

12. Output Voltage Table For A 10 K Thermistor

13. Self-Heat Self-Heating of a thermistor is denoted by the amount of power that will raise the temperature by 1�C The amount of voltage allowed depends on the dissipation constant (DC) For a 10 k? NTC, DC is specified by supplier as 5.5 mW / C Power = V^2 / R = 25 / 20k = 1.25 mW Temperature Rise = Power / DC = 1.25 / 5.5 = 0.2 �C

14. 8-bit A/D CONVERTER Wide power supply range, 3-6V 4 MHZ internal clock Built-in sample and hold 40,000 samples per sec low power consumption, 6mW Using 5 V reference voltage, minimum voltage is 5 / 256 = 0.019 V

15. Motion Sensor Circuit Microphone Binary Counter Timer AND gate

16. Block Diagram

17. Electret Condenser Microphone Characteristics Excellent noise-canceling properties Works well in environments where vibration, low-frequency noise, and electromagnetic interference (EMI) exists Omni-directional - picks up sound equally well from any direction Flat frequency response from 5 Hz to 10 kHz

18. Electret Microphone Schematic

19. Binary Counter Binary word stored in counter represents the number of clock pulses that have occurred at the clock input. Input clock pulses cause flip-flops of the counter to change state By watching the outputs of the flip-flops you can determine how many clock pulses have been applied.

20. Schematic

21. Device Hardware

22. Device Hardware (cont.) Microcontroller Microchip Corp. PIC16F876 Brief Architecture Description Features EEPROM 24LC16B Functions and Features

23. Microcontroller of Choice Fast On-board EEPROM Up to 20 MHz Cheap Better than Basic Stamp 20 to 100 times faster 5 Times Cheaper Smaller Footprint �F� denotes Flash EEPROM Up to 10,000,000 erase write cycles

24. PIC16F876 Architecture RISC-based Harvard Architecture Has separate program and data memory busses Data bus width is 8 bits Low complexity; instruction set is small and the instructions are basic Fast instruction execution time

25. Harvard Architecture

26. PIC16F876 Features Operating Speed of DC 20MHz 200ns instruction cycle 8K X 14 word of FLASH Program Memory Operating voltage range of 2V-5.5V High Sink/Source Current 25 mA On-Board A/D converter On-Board USART (Universal Synchronous Asynchronous Receiver Transmitter)

27. 24LC16B EEPROM 8-pin DIP package Organized as 8 blocks of 256 X 8 bit memory with a 2-wire serial interface Guarantees 1,000,000 erase/write cycles 200 years of data retention

28. 24LC16B EEPROM Block Diagram

29. PIC16F876 Microcontroller

30. Required Equipment EPIC Programmer Runs on two 9V batteries Standard DB25 Cable to Parallel Port Programs 18-, 8-, and 14 pin chips Programs surface-mount (with adapter) Portable PICBasic Compiler Compatible with EPIC Supports models with 8 to 40 pins Generates ASM and HEX code Useful Serial I/O Commands for the PIC16F8XX ZIF Adapter Allows for 40 pin or 28 pin DIP programming Attaches to the 10-pin port

31. Specification of Program Button Monitor Menu Button Play Button Feed Button Sensor Reading Analog Temperature Value Digital Pulse Alarm Notification Drive G12032 LCD Display Module Clock Display Game Graphics + Animation Interface for Menus

33. Button Monitor Port A 2-4, pins 4-6 Detected in the �Main Loop� of program Software-debounced Pin RA4: �Feed� Button Used in game mode and for menu options Pin RA5: �Play� Button Used in game mode and for menu options Pin RA6: �Menu� Button Used to bring up menus for the user

34. Sensor Reading Port B pins 5-7 Monitored and/or recorded in �Main Loop� Temperature Sensor Circuit Pins RB5, RB6, and RB7 Utilizes A/D converter 0-5V analog input from thermistor circuit is changed to digital value If value changes too much from the calibrated �normal�, then alarm sounds Movement Sensor Circuit Pin RA5 Only 1 input from �smart� movement circuit: On (3.5-5v) or Off (0-1v) Timed Power Line RB2 On 5 seconds, Off 1 second

35. Drive G12032 LCD

37. Store Sensor Data in External 24LC16B EEPROM Port A pins RA0, RA1 4 bytes of data per store

38. Sound Alarm Port B pin RB0 Will sound alarm Buzzer sounds a tone PIC program will utilize the �Sound� function EX: �Sound 0 (100,10,50,10)� will play two consecutive notes on line RB0

39. Budget

40. MILESTONE marketing plan location or contact name/phone budget location or contact name/phone post mortem location or contact name/phone submit questions location or contact name/phone