1 / 10

System Software Design

System Software Design. String-less Harp Sam Tjoelker. General System Design. MCU: CY8C29466 MCU Bus Frequency: 24 MHz Memory Requirements: 1 KB ROM, 100 B RAM 4 digital blocks for interrupts, 1-2 digital blocks for PWM Kernel Choice – Time slice. Kernel Task Design. 11 tasks:

indiya
Download Presentation

System Software Design

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. System Software Design String-less Harp Sam Tjoelker

  2. General System Design • MCU: CY8C29466 • MCU Bus Frequency: 24 MHz • Memory Requirements: 1 KB ROM, 100 B RAM • 4 digital blocks for interrupts, 1-2 digital blocks for PWM • Kernel Choice – Time slice

  3. Kernel Task Design • 11 tasks: • Start Task • Checkstring Task • 8 “String” ISR’s • 1 Counter ISR

  4. Start Task Description: • Initializes system • Period: once (at start-up) • Execution time ~ 1s

  5. Checkstring Task Description: • Checks for “string” flag • Stops PWM and counter • Starts PWM and counter with appropriate frequency seed • Clears “string” flag • Period: periodic (8ms) • Execution time ~ 50us

  6. “String” ISR Description: • Sets appropriate “string” flag • Period: sporadic (worst case: 2ms) • Execution time ~ 2us

  7. Counter ISR Description: • Stops PWM and counter • Period: sporadic (worst case:8ms) • Execution time ~ 2us

  8. CPU load L max= (50us) + (2us) + 8*(2us) + (2us) (8ms) (2ms) (2ms) (8ms) L max= 14.5%

  9. Modules

  10. Data Flow Diagram boot.asm main.c

More Related