Embedded C workshop

Embedded C workshop

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  By: Mostafa El-koumy Day#1 Embedded
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  Introduction ? o Introduction toEmbedded C. o Embedded Software Architecture. o Memory usage. o Embedded Development Environment. o Interrupts. o Keywords. o Some Embedded Systems concepts. By: Mostafa El-koumy
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  INTRODUCTION  Embedded Systemsis all things around you which have something called electronic brain to make some sort of artificial intelligence.  Embedded C is a prober subset of C language suitable for Embedded systems, it defines only a new concept of writing software.  Using Embedded C, we should handle everything used in the program like Memory Management, HW Registers, interrupts, …. Etc. By: Mostafa El-koumy
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  MISRA RULES  MotorIndustry Software Reliability Association.  Collaboration between engineering consultancies which seeks to promote best practice in developing Automotive Systems and other embedded systems.  To this end MISRA publishes documents that provide accessible information for engineers and management, and holds events to permit the exchange of experiences between practitioners.  URL : www.misra.org.uk  EX: By: Mostafa El-koumy
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  EMBEDDED SOFTWARE ARCHITECTURE By:Mostafa El-koumy
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  EMBEDDED SOFTWARE ARCHITECTURE(CON’T) By: Mostafa El-koumy
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  CODE FLOW  Allthe code is running within infinite loop in main except:  Initialization code.  Interrupt handlers, interrupt service routines (ISR).  The other code runs normally int main (void) { intitializeModule(); sei(); while(1){ startApplication(); } return 0; } By: Mostafa El-koumy
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  BACKGROUND/FOREGROUND TASKS (LOWCOST) By: Mostafa El-koumy
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  SOFTWARE MODELING Function C file Module Project Cfile(s) H file(s) SW module Uart.c Uart.h Uart_irq.c Uart_cfg.h
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  MEMORY USAGE BYLINKER SCRIPT  The HW Registers  Stack space that grow down  Local variables  Functions return address  Heap Space that grow up  Zero default initialized variables  Initialized with value by developer By: Mostafa El-koumy I/O Addresses Stack (grow down) Heap (Grow up) Un-initialized data (.BSS) Initialized data
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  DEVELOPMENT ENVIRONMENT  IDEwhich has  Text editor.  Cross compiler produce machine language By: Mostafa El-koumy
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  DEVELOPMENT ENVIRONMENT  DevelopmentKit By: Mostafa El-koumy
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  DEVELOPMENT ENVIRONMENT  Incircuit Debugger (ICD)  HW device connects to the microprocessor using JTAG/SWD interface to support external control of the microprocessor using debugger.  Restrictions of debugging capabilities is specified by the microprocessor. By: Mostafa El-koumy
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  DEVELOPMENT ENVIRONMENT  Incircuit Emulator (ICE)  HW device used to debug embedded SW. it replaces the microprocessor with control over all the aspects of it and it usually emulate all the microprocessor family. By: Mostafa El-koumy
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  PROGRAMMING PROCESS DIAGRAM By:Mostafa El-koumy
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  GPIO MODULE Exercise 1 By: MostafaEl-koumy
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  INTERRUPTS  an interruptis a signal to the processor emitted by hardware or software indicating an event that needs immediate attention. An interrupt alerts the processor to a high-priority condition requiring the interruption of the current code the processor is executing.  Interrupt sources  Internal peripherals.  External interrupts.  SW interrupts.  Exception thrown by processors. By: Mostafa El-koumy
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  INTERACTIVE QUESTIONS  Maskable interrupt?  Non-Mask able interrupts?  Level triggered external interrupt?  Edge triggered external interrupt?  Interrupt nesting? By: Mostafa El-koumy
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  INTERRUPT TIMING  Interruptlatency?  Context?  Interrupt response?  Interrupt recovery? By: Mostafa El-koumy
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  EMBEDDED KEYWORDS (INTERACTIVE) Scope and life time with keywords:  Static local  Static global  Volatile  Const  Extern  register By: Mostafa El-koumy
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  FUNCTIONS VS MACROS Macros in completely text replacement so it increase the code size and duplications.  Function is preferred. By: Mostafa El-koumy
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  MACROS VS INLINEFUNCTIONS  In Inline functions Compiler substitute the function call by function code like MACROS.  MACROS is supported by preprocessor so all the IDEs supports it.  Inline is supported by some compilers.  Inline function performs type checking but MACROs not.  Inline function could be traced but MACROs not.  Some compiler disable inline function when the its code is large.
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  Exercise 2 By: Mostafa El-koumy UARTMODULE
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  Thank you for yourattention! Any Questions? By: Mostafa El-koumy
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  CONTACT DETAILS  MostafaEl-koumy  Embedded SW Developer  mostafa.elkoumy@gmail.com