System Software Design Review

 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

 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

 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

 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