For sophomore-level courses in Assembly Language Programming in Computer Science, Embedded Systems Design, Real-Time Analysis, Computer Engineering, or Electrical Engineering curricula. Requires prior knowledge of C, C++, or Java. This text is useful for Computer Scientists, Computer Engineers, and Electrical Engineers involved with embedded software applications. This book is intended to provide a highly motivating context in which to learn procedural programming languages. The ultimate goal of this text is to lay a foundation that supports the multi-threaded style of programming and high-reliability requirements of embedded software. It presents assembly the way it is most commonly used in practice - to implement small, fast, or special-purpose routines called from a main program written in a high-level language such as C. Students not only learn that assembly still has an important role to play, but their discovery of multi-threaded programming, preemptive and non-preemptive systems, shared resources, and scheduling helps sustain their interest, feeds their curiosity, and strengthens their preparation for subsequent courses on operating systems, real-time systems, networking, and microprocessor-based design.

Table of Contents:
1 Introduction 1.1 WHAT IS AN EMBEDDED SYSTEM? 1.2 WHAT’S UNIQUE ABOUT THE DESIGN GOALS FOR EMBEDDED SOFTWARE? 1.3 What Does "Real-Time" Mean? 1.4 What Does "multithreading" mean? 1.5 HOW POWERFUL ARE EMBEDDED PROCESSORS? 1.6 WHAT PROGRAMMING LANGUAGES ARE USED? 1.7 HOW IS BUILDING AN EMBEDDED APPLICATION DIFFERENT? 1.8 HOW BIG ARE TYPICAL EMBEDDED PROGRAMS? PROBLEMS 2 Data Representation 2.1 FIXED-PRECISION BINARY NUMBERS 2.2 POSITIONAL NUMBER SYSTEMS 2.2.1 Binary-to-Decimal Conversion 2.2.2 Decimal-to-Binary Conversion 2.2.3 Hexadecimal — A Shorthand for Binary 2.2.4 Fixed Precision, Rollover and Overflow 2.3 BINARY REPRESENTATION OF INTEGERS 2.3.1 Signed Integers 2.3.2 Positive and Negative Representations of the Same Magnitude 2.3.3 Interpreting the Value of a 2’s-Complement Number 2.3.4 Changing the Sign of Numbers with Integer and Fractional Parts 2.3.5 Binary Addition and Subtraction 2.3.6 Range and Overflow 2.4 BINARY REPRESENTATION OF REAL NUMBERS 2.4.1 Floating-Point Real Numbers 2.4.2 Fixed-Point Real Numbers 2.5 ASCII REPRESENTATION OF TEXT 2.6 BINARY-CODED DECIMAL (BCD) PROBLEMS 3 Implementing Arithmetic 3.1 2’s Complement and hardware complexity 3.2 MULTIPLICATION AND DIVISION 3.2.1 Signed vs. Unsigned Multiplication 3.2.2 Shifting Instead of Multiplying or Dividing by Powers of 2 3.2.3 Multiplying by an Arbitrary Constant 3.2.4 Dividing by an Arbitrary Constant 3.3 ARITHMETIC FOR FIXED-POINT REALS 3.3.1 Fixed-Point Using a Universal 16.16 Format 3.3.2 Fixed-Point Using a Universal 32.32 Format 3.3.3 Multiplication of 32.32 Fixed Point Reals 3.3.4 Example: Multiplying two 4.4 Fixed Point Reals PROBLEMS 4 Getting the Most Out of C 4.1 Integer Data Types 4.1.1 Integer Range and the Standard Header File LIMITS.H 4.2 BOOLEAN Data Types 4.3 Mixing Data Types 4.4 Manipulating Bits in Memory 4.4.1 Testing Bits 4.4.2 Setting, Clearing, and Inverting Bits 4.4.3 Extracting Bits 4.4.4 Inserting Bits 4.5 Manipulating Bits in INPUT/OUTPUT PORTS 4.5.1 Write-Only I/O Devices 4.5.2 I/O Devices Differentiated by Reads Versus Writes 4.5.3 I/O Devices Differentiated by Sequential Access 4.5.4 I/O Devices Differentiated by Bits in the Written Data 4.6 Accessing Memory-Mapped I/O Devices 4.6.1 Accessing Data Using a Pointer 4.6.2 Arrays, Pointers, and the “Address of” Operator 4.7 Structures 4.7.1 Packed Structures 4.7.2 Bit Fields 4.8 Variant Access 4.8.1 Casting the Address of an Object 4.8.2 Using Unions Problems 5 Programming in Assembly Part 1: Computer Organization 5.1 Memory 5.1.1 Data Alignment 5.2 The Central Processing Unit (CPU) 5.2.1 Other Registers 5.2.2 The Fetch-Execute Cycle 5.3 Input/Output (I/O) 5.4 Introduction to the ARM® CortexTM- M3 V7M Architecture 5.4.1 Internal Organization 5.4.2 Instruction Pipelining 5.4.3 Memory Model 5.4.4 Bit-Banding 5.5 ARM ASSEMBLY LANGUAGE 5.5.1 Instruction Formats and Operands 5.5.2 Translating Assembly into Binary Problems 6 Programming in Assembly Part 2: Data Manipulation 6.1 LOADING CONSTANTS INTO REGISTERS 6.2 LOADING MEMORY DATA INTO REGISTERS 6.3 STORING DATA FROM REGISTERS TO MEMORY 6.4 CONVERTING SIMPLE C ASSIGNMENT STATEMENTS INTO ARM ASSEMBLY 6.5 MEMORY ADDRESS CALCULATIONS 6.6 MEMORY ADDRESSING EXAMPLES 6.6.1 Translating C Pointer Expressions to Assembly 6.6.2 Translating C Subscript Expressions to Assembly 6.6.3 Translating Structure References to Assembly 6.7 STACK INSTRUCTIONS 6.8 DATA PROCESSING INSTRUCTIONS 6.8.1 Updating the Flags in the APSR 6.8.2 Arithmetic Instructions 6.8.3 Bit Manipulation Instructions 6.8.4 Shift Instructions 6.8.5 Bitfield Manipulation Instructions 6.8.6 Miscellaneous Bit, Byte and Halfword Instructions PROBLEMS 7 Programming in Assembly Part 3: Control Structures 7.1 INSTRUCTION SEQUENCING 7.2 IMPLEMENTING DECISIONS 7.2.1 Conditional Branch Instructions 7.2.2 If-Then and If-Then-Else Statements 7.2.3 Compound Conditionals 7.1.4 The “If-Then” (IT) Instruction 7.2 IMPLEMENTING LOOPS 7.2.1 Speeding Up Array Access 7.3 IMPLEMENTING FUNCTIONS 7.3.1 Function Call and Return 7.3.2 Register Usage 7.3.3 Parameter Passing 7.3.4 Return Values 7.3.5 Temporary Variables 7.3.6 Preserving Registers PROBLEMS 8 Programming in Assembly Part 4: I/O Programming 8.1 THE CORTEX-M3 I/O HARDWARE 8.1.1 Interrupts and Exceptions 8.1.2 Thread and Handler Modes 8.1.3 Entering the Exception Handler 8.1.4 Returning from the Exception Handler 8.1.5 Latency Reduction 8.1.6 Priorities and Nested Exceptions 8.2 SYNCHRONIZATION, TRANSFER RATE, AND LATENCY 8.3 BUFFERS AND QUEUES 8.3.1 Double Buffering 8.4 ESTIMATING I/O PERFORMANCE CAPABILITY 8.4.1 Polled Waiting Loops 8.4.2 Interrupt-Driven I/O 8.4.3 Direct Memory Access 8.4.4 Comparison of Methods PROBLEMS 9 Concurrent Software 9.1 FOREGROUND/BACKGROUND SYSTEMS 9.1.1 Thread State and Serialization 9.1.2 Managing Latency 9.1.3 Interrupt Overrun 9.1.4 Moving Work into the Background 9.2 MULTI-THREADED PROGRAMMING 9.2.1 Concurrent Execution of Independent Threads 9.2.2 Context Switching 9.2.3 Non-preemptive (Cooperative) Multithreading 9.2.4 Preemptive Multithreading 9.3 SHARED RESOURCES AND CRITICAL SECTIONS 9.3.1 Disabling Interrupts 9.3.2 Disabling Task Switching 9.3.3 Spin Locks 9.3.4 Mutex Objects 9.3.5 Semaphores PROBLEMS 10 Scheduling 10.1 THREAD STATES 10.2 PENDING THREADS 10.3 CONTEXT SWITCHING 10.4 ROUND-ROBIN SCHEDULING 10.5 PRIORITY-BASED SCHEDULING 10.5.1 Resource Starvation 10.5.2 Priority Inversion 10.5.3 The Priority Ceiling Protocol 10.5.4 The Priority Inheritance Protocol 10.6 ASSIGNING PRIORITIES 10.6.1 Deadline-Driven Scheduling 10.6.2 Rate-Monotonic Scheduling 10.7 DEADLOCK 10.8 WATCHDOG TIMERS PROBLEMS 11 Memory Management 11.1 OBJECTS IN C 11.2 SCOPE 11.2.1 Refining Local Scope 11.2.2 Refining Global Scope 11.3 LIFETIME 11.4 AUTOMATIC ALLOCATION 11.4.1 Storage Class “Register” 11.5 STATIC ALLOCATION 11.6 THREE PROGRAMS TO DISTINGUISH STATIC FROM AUTOMATIC 11.6.1 Object Creation 11.6.2 Object Initialization 11.6.3 Object Destruction 11.7 DYNAMIC ALLOCATION 11.7.1 Fragmentation 11.7.2 Memory Allocation Pools 11.8 AUTOMATIC ALLOCATION WITH VARIABLE SIZE (alloca) 11.8.1 Variable-Size Arrays 11.9 RECURSIVE FUNCTIONS AND MEMORY ALLOCATION PROBLEMS 12 Shared Memory 12.1 RECOGNIZING SHARED OBJECTS 12.2 REENTRANT FUNCTIONS 12.3 READ-ONLY DATA 12.3.1 Type Qualifier "const" 12.4 CODING PRACTICES TO AVOID 12.4.1 Functions That Keep Internal State in Local Static Objects 12.4.2 Functions That Return the Address of a Local Static Object 12.5 ACCESSING SHARED MEMORY 12.5.1 The Effect of Processor Architecture 12.5.2 Read-Only and Write-Only Access 12.5.3 Type Qualifier “volatile” PROBLEMS 13 System Initialization 13.1 MEMORY LAYOUT 13.2 THE CPU AND VECTOR TABLE 13.3 C RUN-TIME ENVIRONMENT 13.3.1 Copying Initial Values from Non-Volatile Memory into the Data Region 13.3.2 Zeroing Uninitialized Statics 13.3.3 Setting Up a Heap 13.4 SYSTEM TIMER 13.5 OTHER PERIPHERAL DEVICES