Front Cover -- Software Engineering for Embedded Systems -- Copyright Page -- Contents -- Software Engineering for Embedded Systems: A Roadmap -- Foreword to Software Engineering for Embedded Systems -- Acknowledgments -- About the Editors -- About the Authors -- 1 Software Engineering of Embedded and Real-Time Systems -- Software engineering -- Embedded systems -- Embedded systems are reactive systems -- Real-time systems -- Types of real-time systems - soft and hard -- Differences between real-time and time-shared systems -- Examples of hard real-time -- Based on signal sample, time to perform actions before next sample arrives -- Hard real-time systems -- Real-time event characteristics -- Real-time event categories -- Efficient execution and the execution environment -- Efficiency overview -- Resource management -- Challenges in real-time system design -- Response time -- Recovering from failures -- The embedded system software build process -- Distributed and multi-processor architectures -- Software for embedded systems -- Super loop architecture -- Power-save super loop -- Window lift embedded design -- Hardware abstraction layers (HAL) for embedded systems -- Summary -- 2 Embedded Systems Hardware/Software Co-Development -- Today's embedded systems - an example -- HW/SW prototyping users -- HW/SW prototyping options -- Prototyping decision criteria -- Choosing the right prototype -- Industry design chain -- The need to change the design flow -- Different types of virtual prototypes -- A brief history of virtual prototypes -- The limits of proprietary offerings -- What makes virtual prototypes fast -- Standardization: the era of SystemC TLM-2.0 -- SystemC TLM-2 abstraction levels -- Architecture virtual prototypes -- Software virtual prototypes -- Summary - the growing importance of virtualization.

3 Software Modeling for Embedded Systems -- When and why should you model your embedded system? -- Modeling -- What is a modeling language? -- Examples of modeling languages -- The V diagram promise -- So, why would you want to model your embedded system? -- When should you model your embedded system? -- Mission- and safety-critical applications -- Highly complex applications and systems -- Operational complexity -- Cost of defect versus when detected -- Large development teams require modeling -- Modeling is often the only choice -- So - modeling is great, but aren't all models wrong? -- You have your prototype - now what? -- Conclusion -- Next steps - try it! -- Closed-loop control with a DC motor -- Learn more about prototyping with a downloadable kit -- Designing applications with the NI Statechart Module -- Design and simulate a brushed dc motor h-bridge circuit -- Multi-domain physical modeling with open-source Modelica models -- References -- 4 Software Design Architecture and Patterns for Embedded Systems -- Overview of architecture and design -- Architecture is about system-wide optimization -- Three levels of design -- What are design patterns? -- Must I use object-oriented techniques to use design patterns? -- An architectural example -- Name: port proxy pattern -- Abstract -- Problem context -- Pattern structure and behavior -- Consequences -- Using patterns -- Making trade-off decisions -- Software architecture categories and views -- Primary architectural views -- Subsystem and component view -- Concurrency and resource view -- Deployment view -- Distribution view -- Dependability view -- Secondary viewpoints -- Summary -- References -- 5 Real-Time Building Blocks: Events and Triggers -- Events and triggers -- Room temperature unit -- Event system -- Event handle -- Event methods -- Event data structure -- Reentrancy.

Disable and enable interrupts -- EnterCritical and ExitCritical -- Semaphores -- Implementation with Enter/ExitCritical -- Event processing -- Integration -- Triggers -- Blinking LED -- Design idea -- Tick timer -- Trigger interface -- Trigger descriptor -- Data allocation -- SetTrigger -- IncTicks -- Making it reentrant -- Initialization -- Blink! -- Beep! -- Real-time aspects -- Summary and source code -- 6 Hardware's Interface to Embedded Software -- Introduction -- Collaborate with the hardware team -- Proactive collaboration -- Ambassadors -- Register design tools -- Co-development activities -- System integration -- Useful hardware design aspects -- Notification of hardware events -- Launching tasks in hardware -- Bit field alignment -- Fixed bit positions -- Block version number -- Debug hooks -- Supporting multiple versions of hardware -- Compile-time switches -- Build-time switches -- Run-time switches -- Self-adapting switches -- Difficult hardware interactions -- Atomic register access -- Mixed bit types in the same register -- Edge vs. level interrupts -- Testing and troubleshooting -- Temporary hooks -- Permanent hooks -- Conclusion -- Best practices -- 7 Embedded Software Programming and Implementation Guidelines -- Introduction -- Principles of high-quality programming -- Readability -- Maintainability -- Testability -- What sets embedded apart from general programming -- Starting the embedded software project -- Hardware platform input -- Project files/organization -- Source files written locally -- Source files from company libraries -- Libraries from third parties -- Libraries from compiler/linker toolset -- Team programming guidelines -- Syntax standard -- Code white space -- Tabs in source files -- Alignment within source -- Safety requirements in source code -- Variable structure -- Variable declarations -- Global variables.

File scope variables -- Local variables -- Data types -- Definitions -- Conditional compilation -- #define -- 8 Embedded Operating Systems -- Foreground/background systems -- Real-time kernels -- RTOS (real-time operating system) -- Critical sections -- Task management -- Assigning task priorities -- Determining the size of a stack -- The idle task -- Priority levels -- The ready list -- Preemptive scheduling -- Scheduling points -- Round-robin scheduling -- Context switching -- Interrupt management -- Handling CPU interrupts -- Non-kernel-aware interrupt service routine (ISR) -- Processors with multiple interrupt priorities -- All interrupts vector to a common location -- Every interrupt vectors to a unique location -- The clock tick (or system tick) -- Wait lists -- Time management -- Resource management -- Resource management, disable/enable interrupts -- Resource management, semaphores -- Resource management, notes on semaphores -- Resource management, priority inversions -- Resource management, mutual-exclusion semaphores (mutex) -- Resource management, deadlocks (or deadly embrace) -- Synchronization -- Synchronization, semaphores -- Synchronization, credit tracking -- Bilateral rendez-vous -- Message passing -- Messages -- Message queues -- Flow control -- Clients and servers -- Memory management -- Summary -- 9 Software Reuse By Design in Embedded Systems -- Why does software reuse matter? -- What limits software reuse? -- Kinds of software reuse -- Implementing reuse by layers -- Going to the next level -- Introducing the component factory -- Factory hardware configuration -- Factory software configuration -- How the factory aids reusability -- RTOS agnosticism -- Arbitrary extensibility -- Conclusion -- References -- Cost estimations -- Defect testing -- Libraries -- 10 Software Performance Engineering for Embedded Systems.

Example: latency vs. throughput in an eNodeB application -- Performance patterns and anti-patterns -- References -- 11 Optimizing Embedded Software for Performance -- The code optimization process -- Using the development tools -- Compiler optimization -- Basic compiler configuration -- Enabling optimizations -- Additional optimization configurations -- Using the profiler -- Background - understanding the embedded architecture -- Resources -- Basic C optimization techniques -- Choosing the right data types -- Use intrinsics to leverage embedded processor features -- Functions calling conventions -- Pointers and memory access -- Ensuring alignment -- Restrict and pointer aliasing -- Loops -- Communicating loop count information -- Hardware loops -- Additional tips and tricks -- Memory contention -- Use of unaligned accesses -- Cache accesses -- Inline small functions -- Use vendor run-time libraries -- General loop transformations -- Loop unrolling -- Background -- Implementation -- Multisampling -- Background -- Implementation procedure -- Implementation -- Partial summation -- Background -- Implementation procedure -- Implementation -- Software pipelining -- Background -- Implementation -- Example application of optimization techniques: cross-correlation -- Setup -- Original implementation -- Step 1: use intrinsics for fractional operations and specify loop counts -- Step 2: specify data alignment and modify for multisampling algorithm -- Step 3: assembly-language optimization -- 12 Optimizing Embedded Software for Memory -- Introduction -- Code size optimizations -- Compiler flags and flag mining -- Target ISA for size and performance tradeoffs -- Tuning the ABI for code size -- Caveat emptor: compiler optimization orthogonal to code size! -- Memory layout optimization -- Overview of memory optimization -- Focusing optimization efforts.

Vectorization and the dynamic code: compute ratio.