System Software Design Doorbell Jukebox Henry Arbicor and

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System Software Design Doorbell Jukebox Henry Arbicor and Arthur Bingcang

System Software Design Doorbell Jukebox Henry Arbicor and Arthur Bingcang

General System Design MCU – Freescale MCF 52233 Bus Frequency – 60 MHz Memory

General System Design MCU – Freescale MCF 52233 Bus Frequency – 60 MHz Memory Requirements ◦ 12 k. B RAM ◦ 37 k. B FLASH, no paging Timeslice Kernel ◦ Timeslice period: 10 ms

Tasks 4) 5) 6) 7) 8) Start Task MP 3 Task Push-button Task LCD

Tasks 4) 5) 6) 7) 8) Start Task MP 3 Task Push-button Task LCD Task Play Task

Start Task Initializes the system Sets up the order in which the other tasks

Start Task Initializes the system Sets up the order in which the other tasks will run Period: Once at Start-up Execution Time: 100 ms

MP 3 Task Reads MP 3’s from MMC card and displays song names on

MP 3 Task Reads MP 3’s from MMC card and displays song names on the LCD Sets pointer that will move when different songs are selected Period: 100 ms (periodic) Execution Time: 5 ms

Push-button Task Recognizes push-button press De-bouncing Sets state ◦ ◦ ◦ Up Down Select

Push-button Task Recognizes push-button press De-bouncing Sets state ◦ ◦ ◦ Up Down Select Sequential Doorbell • Period: 10 ms (sporadic) • Execution Time: 5 us

LCD Task Display’s song names Adjusts display according to current state Period: 100 ms

LCD Task Display’s song names Adjusts display according to current state Period: 100 ms (periodic) Execution Time: 2. 5 ms

Play Task When in Doorbell state, decodes and plays the selected song Period: 10

Play Task When in Doorbell state, decodes and plays the selected song Period: 10 ms (periodic) Execution Time: 3 ms

CPU Load (max) = 5 ms/100 ms + 5 us/10 ms + 2. 5

CPU Load (max) = 5 ms/100 ms + 5 us/10 ms + 2. 5 ms/100 ms + 3 ms/10 ms =. 3755 = 37. 55% Load (average) = 5 ms/100 ms + 2. 5 ms/100 ms =. 075 = 7. 5%

Modules Tasks Jukebox. c Start Task MP 3 Task Push-button Task LCD Task Play

Modules Tasks Jukebox. c Start Task MP 3 Task Push-button Task LCD Task Play Task LCD. c Public Functions and Data Play. Song() Stop. Song() None All LCD Functions None OCDelay() OCDelay. Init() By Todd Morton OCDelay. c By Todd Morton Coldfire MP 3 Decoder Interface By Motorola Embedded File Systems Library By Lennart Ysboodt, Michael De Nil

Dataflow Diagrams: LCD Jukebox. c LCD I/O Push-button Task Button MP 3 Task LCD

Dataflow Diagrams: LCD Jukebox. c LCD I/O Push-button Task Button MP 3 Task LCD

Dataflow Diagrams: Audio Out Jukebox. c External Hardware MMC Card MP 3 Task DAC

Dataflow Diagrams: Audio Out Jukebox. c External Hardware MMC Card MP 3 Task DAC Pushbutton Clock Play Task Speaker