1 / 13

ATV INSTRUMENTATION DISPLAY

ATV INSTRUMENTATION DISPLAY . System Software Design Ed Raezer. General System Design. Motorola MC9S12C32 w/ 32k Bytes EEPROM, 2K Bytes RAM 16 MHz Bus Frequency Memory Requirements for Project 8K ROM, 1K RAM. Kernel Selection. Kernel Choice: MicroC/OS-II

ishi
Download Presentation

ATV INSTRUMENTATION DISPLAY

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. ATV INSTRUMENTATIONDISPLAY System Software Design Ed Raezer

  2. General System Design • Motorola MC9S12C32 w/ 32k Bytes EEPROM, 2K Bytes RAM • 16 MHz Bus Frequency • Memory Requirements for Project 8K ROM, 1K RAM

  3. Kernel Selection • Kernel Choice: MicroC/OS-II Real-time preemptive multitasking kernel with a 1 ms tick period • Configured for my program • Modify (os_cfg.h)

  4. Task Priority 4- Start Task 5- User Interface 6- RPM Task 7- Speed Task 8- Clock Task

  5. Start Task Description: -Initializations -Creates Tasks -Priority #4 -Period: once (at startup) -Execution time: 200 msec

  6. Clock Task Description: -Retrieves time from RTC -Updates time buffer -Period: 1 sec (Periodic) -Execution Time: 35 usec -L = .000035

  7. User Interface Task Description: -Monitors the buttons -Sets Clock -Activates LEDs -Changes Display Modes -Execution Time: 1 msec -Period: 10 ms -L = .1

  8. RPM Task Description: -Retrieves pulse count from pulse accumulator and converts to RPMs -Updates RPM buffer -Period: 500 msec -Execution Time: 20 usec -L = .00004

  9. Speed Task Description: -Monitors wheel sensor, counts pulses and converts to speed and distance -Updates odometer -Updates speed buffer -Execution time: 20 usec -Period: quick as 50msec (ISR driven) -L = .0004

  10. ISR • Creates a semaphore everytime a wheel sensor pulse is detected so Wheel Task can run • Period: up to 50 msec • Execution time: 300 nsec • L = .000006

  11. CPU Load L = .000035+.1+.00004+.0004+.000006= .100481 LMAX = 10.05%

  12. Modules and Functions

  13. Dataflow Diagram

More Related