System Software Design Vinh Le General System Design

System Software Design Vinh Le

General System Design � MCU: � Bus Freescale Kinetis K 60512 ARM Cortex M 4 Frequency: 50 MHz � Available Memory: ◦ 512 KB Flash ◦ 64 KB SRAM � Memory Required: ◦ 10 KB Flash ◦ 4 KB SRAM

Kernel � MQX RTOS provided by Freescale ◦ Real-time preemptive multitasking Kernel � Events Services for Task Synchronization ◦ Semaphores, Mutexes, and Messages � Time Delays ◦ Tick period: 1 ms � Real-Time TCP/IP Communication Suite (RTCS) ◦ TCP/IP networking application protocols for Web Communication � Tasks ◦ Start Up, Key Task, UI Task, Message Task,

Start Task Description: � Enables all of MCU and Kernel resources and initializes system. � Creates other tasks � Priority #4 � Period: Once (at start-up) � Execution time ~ 1 s

Key Task Description: � Reads the keypad and updates the buffer � Priority #7 � Period 10 ms � Execution time ~ 2. 2 us

User Interface Task Description: � Handles User Inputs ◦ Allows to set the E-Mail address for the device ◦ Displays Message ◦ Navigate through messages � Priority #5 � Period 0. 5 sec � Execution time ~ 2 ms

Message Task Description: � Retrieve E-mail message data ◦ Download data and update message list � Priority #6 � Period: 0. 5 sec � Execution time ~ 50 ms

CPU Load Lmax = 10. 4% Laverage = 3. 5%

Modules Tasks Main. c Start. Task UITask Key. c Key. Task LCD. c Message. c Public Functions and Data Key. Init() Keypend() Lcd. Init() Lcd. Clr. Disp() Lcd. Disp. Strg() Lcd. Move. Cursor() Lcd. Cursor() Message. Task E-mail Data Message List

Keypad Data Flow

Overall Data Flow