Bicycle Information Tracking System
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Transcript of Bicycle Information Tracking System
BICYCLE INFORMATION TRACKING SYSTEM
System Software Design Review
BITS General System Software Design
MCU: NXP LPC2378 ARM7 32-bit 512 KB Flash, 8KB EEPROM and SRAM
Bus Frequency: 20 MHz Approximate Memory requirements:
ROM: ~220 KB maximum Includes FatFS file system, drivers for all
peripherals RAM: ~2 KB SD Card: 1 KB on a FAT formatted 256 MB card
Resources used: 5 GPIO, 1 SPI, Micro-SD card
BITS System Software Design: Kernel
Timeslice based system Shared resources use flags
FatFS file system Open-source system for SD card read/write
Tick period: 1 ms Number of tasks: 4
AppInit, Input Task, SDCard, UI Display
BITS System Software Design: Tasks
Start Task Initializes all resources including LCD, SD card, and GPIO,
checks SD card for previous data. Displays splash screen Only runs at beginning Execution time: 3 seconds
Input task Monitors GPIO port P3 for input from Hall Effect Sensor
Uses this information to perform calculations Monitors GPIO port P4 for input from switches, as well as
information from the touchscreen Toggles turn signals, changes data shown on screen
Monitors input from Touch Screen Period: 1 ms Execution time: ~10 us
BITS System Software Design: Tasks
SDCard task Writes strings and data to SD card when prompted
by the user Period: ~20 ms (Sporadic) Execution time: ~3 ms
UI Display task Controls displayed information on the screen
based on Touchscreen/GPIO input, also calculates information obtained from P3 to determine distance and speed.
Period: ~10 ms Execution time: ~1 ms
BITS System Software Design: Tasks
Maximum CPU load: 26%
Average CPU load: 8%
BITS Data Flow: GPIO/Touch Task
BITS Data Flow: UI Task
BITS Data Flow: SD Card Task
BITS Data Flow: State Diagram
BITS Modules and Functions
Microsoft Excel Worksheet
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