02-06-2012, 01:03 PM
BLACK BOX FOR VEHICLES
blackbox.ppt (Size: 1.25 MB / Downloads: 926)
INTRODUCTION
Record informational data
Vehicle mapping & accident alert
Vehicle security system
Using PIC16F877A
Components
EMBEDDED SYSTEM
Any electronic system that uses a CPU chip, but that is not a general purpose work station, desktop or laptop computer.
A special purpose computer system designed to perform a dedicated function.
COMPONENT DESCRIPTION
40 pin device
Operating speed DC - 20MHz clock input
Operating voltage range – 2V to 5.5V
Flash memory 8k
Data memory 368 bytes
EEPROM 256 bytes
5 ports A,B,C,D,E
TEMPERATURE SENSOR
Precision integrated-circuit temperature sensor
Calibrated directly in ° Celsius (Centigrade)
Linear + 10.0 mV/°C scale factor
0.5°C accuracy guarantee able (at +25°C)
Rated for full −55° to +150°C range
Suitable for remote applications
Low cost due to wafer-level trimming
Operates from 4 to 30 volts
COLLISION SENSOR
Uses the piezoelectric effect to measure pressure, acceleration, strain or force by converting them to an electrical charge
Works on piezoelectric effect
GPS
A space based navigation & positioning system
Provides location and time information in all weather, anywhere on or near the earth
Every point on earth has a uniform and unique “address”
Based on WGS84 DATUM
Distance (ranging) system