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2.2 Boolean Functions and Truth Tables ................................................................................45
2.3 Algebraic Manipulation of Boolean Expressions .............................................................48
2.4 Canonical Forms ................................................................................................................49
2.5 Simplification of Boolean Functions .................................................................................52
2.6 What Does This Have To Do With Computers, Anyway? ................................................59
2.6.1 Correspondence Between Electronic Circuits and Boolean Functions ................59
2.6.2 Combinatorial Circuits ............................................................................................60
2.6.3 Sequential and Clocked Logic ................................................................................62
2.7 Okay, What Does It Have To Do With Programming, Then? ..........................................64
2.8 Generic Boolean Functions ..............................................................................................65
2.9 Laboratory Exercises .........................................................................................................69
2.9.1 Truth Tables and Logic Equations Exercises .........................................................70
2.9.2 Canonical Logic Equations Exercises .....................................................................71
2.9.3 Optimization Exercises ...........................................................................................72
2.9.4 Logic Evaluation Exercises .....................................................................................72
2.10 Programming Projects .....................................................................................................77
2.11 Summary ..........................................................................................................................78
2.12 Questions .........................................................................................................................80
Chapter Three System Organization .............................................................................. 83
3.0 Chapter Overview .............................................................................................................83
3.1 The Basic System Components .........................................................................................83
3.1.1 The System Bus ......................................................................................................84
3.1.1.1 The Data Bus ................................................................................................ 84
3.1.1.2 The Address Bus ........................................................................................... 86
3.1.1.3 The Control Bus ............................................................................................ 86
3.1.2 The Memory Subsystem .........................................................................................87
3.1.3 The I/O Subsystem .................................................................................................92
3.2 System Timing ...................................................................................................................92
3.2.1 The System Clock ...................................................................................................92
3.2.2 Memory Access and the System Clock ...................................................................93
3.2.3 Wait States ...............................................................................................................95
3.2.4 Cache Memory ........................................................................................................96
3.3 The 886, 8286, 8486, and 8686 “Hypothetical” Processors ..............................................99
3.3.1 CPU Registers ..........................................................................................................99
3.3.2 The Arithmetic & Logical Unit ................................................................................100
3.3.3 The Bus Interface Unit ............................................................................................100
3.3.4 The Control Unit and Instruction Sets ....................................................................100
3.3.5 The x86 Instruction Set ...........................................................................................102
3.3.6 Addressing Modes on the x86 ................................................................................103
3.3.7 Encoding x86 Instructions ......................................................................................104
3.3.8 Step-by-Step Instruction Execution ........................................................................107
3.3.9 The Differences Between the x86 Processors .......................................................109
3.3.10 The 886 Processor ................................................................................................110
3.3.11 The 8286 Processor ...............................................................................................110
3.3.12 The 8486 Processor ...............................................................................................116
3.3.12.1 The 8486 Pipeline ....................................................................................... 117
3.3.12.2 Stalls in a Pipeline ....................................................................................... 118
3.3.12.3 Cache, the Prefetch Queue, and the 8486 .................................................. 119