Part A Fundamentals of PC Hardware and Software 1
1 BASIC FEATURES OF PC HARDWARE 1
Introduction 1
Bits and Bytes 1
Binary Numbers 3
Hexadecimal Representation 6
ASCII Code 7
The Processor 7
Internal Memory 9
Segments and Addressing 11
Registers 13
Key Points 17
Questions 18
2 REQUIREMENTS FOR USING PC SOFTWARE 20
Introduction 20
Features of the Operating System 20
The Boot Process 21
Input-Output Interface 22
The System Program Loader 22
The Stack 23
Addressing of Instructions and Data 25
Instruction Operands 27
Key Points 27
Questions 28
3 EXECUTING COMPUTER INSTRUCTIONS 29
Introduction 29
Using the DEBUG Program 30
Viewing Memory Locations 31
Machine Language Example Ⅰ：Immediate Data 34
Machine Language Example Ⅱ：Defined Data 38
An Assembly Language Example 41
Using the INT Instruction 42
Saving a Program from Within DEBUG 45
Using the PTR Operator 45
Key Points 46
Questions 47
Part B Fundamentals of Assembly Language 49
4 REQUIREMENTS FOR CODING IN ASSEMBLY LANGUAGE 49
Introduction 49
Assemblers and Compilers 50
Program Comments 50
Reserved Words 51
Identifiers 51
Statements 52
Directives 53
Instructions for Initializing a Program 57
Instructions for Ending Program Execution 59
Example of a Source Program 59
Initializing for Protected Mode 60
Simplified Segment Directives 61
Data Definition 62
Directives for Defining Data 65
The EQu Directive 69
Key Points 70
Questions 71
5 ASSEMBLING，LINKING，AND EXECUTING A PROGRAM 73
Introduction 73
Preparing a Program for Execution 73
Assembling a Source Program 74
Using Conventional Segment Definitions 76
Using Simplified Segment Directives 81
Two-Pass Assembler 83
Linking an Object Program 83
Executing a Program 86
Cross-Reference Listing 86
Error Diagnostics 87
The Assembler Location Counter 89
Key Points 89
Questions 89
6 SYMBOLIC INSTRUCTIONS AND ADDRESSING 91
Introduction 91
The Symbolic Instruction Set 91
Instruction Operands 94
The Mov Instruction 97
Move-and-Fill Instructions 98
Immediate Operands 99
The XCHG Instruction 100
The LEA Instruction 101
The INC and DEC Instructions 101
Extended Move Operations 101
The INT Instruction 103
Aligning Data Addresses 104
Near and Far Addresses 104
The Segment Override Prefix 105
Key Points 105
Questions 106
7 WRITING.COM PROGRAMS 108
Introduction 108
Differences Between an.EXE and a.COM Program 108
Converting into.CoM Format 109
Example of a.CoM Program 110
The.COM Stack 111
Debugging Tips 112
Key Points 112
Questions 113
8 PROGRAMMING REQUIREMENTS FOR LOGIC AND CONTROL 114
Introduction 114
Short，Near，and Far Addresses 115
Instruction Labels 115
The JMP Instruction 116
The LOOP Instruction 118
The Flags Register 119
The CMP Instruction 120
Conditional Jump Instructions 121
Calling Procedures 123
Effect of Program Execution on the Stack 126
Boolean Operations 127
Program：Changing Uppercase to Lowercase 129
Shifting Bits 130
Rotating Bits 132
Jump Tables 134
Organizing a Program 136
Key Points 137
Questions 137
Part C Screen and Keyboard Operations 139
9 INTRODUCTION TO SCREEN AND KEYBOARD PROCESSING 139
Introduction 139
The Screen 140
Setting the Cursor 140
Clearing the Screen 141
INT 21H Function O9H for Screen Display 142
TNT 21H Function OAH for Keyboard Input 144
Program：Accepting and Displaying Names 145
Using Control Characters in a Screen Display 149
INT 21H Function O2H for Screen Display 150
File Handles 150
INT 2IH Function 4OH for Screen Display 151
INT 2IH Function 3FH for Keyboard Input 152
Key Points 154
Questions 154
10 ADVANCED FEATURES OF SCREEN PROCESSING 156
Introduction 156
Video Adapters 157
Setting the Video Mode 157
Using Text Mode 158
Screen Pages 161
Using INT IOH for Text Mode 161
Program：Displaying the ASCII Character Set 167
ASCII Characters for Boxes and Menus 170
Program：Blinking，Reverse Video，and Scrolling 171
Direct Video Display 173
Using Graphics Mode 175
INT IoH for Graphics 177
Program：Setting and Displaying Graphics Mode 180
Determining the Type of Video Adapter 182
Key Points 182
Questions 183
11 ADVANCED FEATURES OF KEYBOARD PROCESSING 185
Introduction 185
The Keyboard 186
Keyboard Shift Status 186
The Keyboard Buffer 187
Using INT 21H for Keyboard Input 188
Using INT 16H for Keyboard Input 189
Extended Function Keys and Scan Codes 191
Program：Selecting from a Menu 193
BIOS INT O9H and the Keyboard Buffer 197
Keying in the Full ASCII Character Set 201
Key Points 201
Questions 202
Part D Data Manipulation 203
12 PROCESSING STRING DATA 203
Introduction 203
Features of String Operations 204
REP：Repeat String Prefix 204
MOVS：Move String Instruction 205
LODS：Load String Instruction 207
STOS：Store String Instruction 208
Program：Using LoDs and STOS to Transfer Data 209
CMPS：Compare String Instruction 211
SCAS：Scan String Instruction 213
Example：Using Scan and Replace 214
Alternative Coding for String Instructions 214
Duplicating a Pattern 215
Program：Right Adjusting a Screen Display 215
Key Points 218
Questions 218
13 ARITHMETIC：I—PROCESSING BINARY DATA 220
Introduction 220
Processing Unsigned and Signed Data 221
Addition and Subtraction 222
Extending Values in a Register 224
Performing Arithmetic on Doubleword Values 225
Multiplication 227
Performing Doubleword Multiplication 231
Special Multiplication Instructions 234
Multiplication by Shifting 235
Division 235
Division by Shifting 239
Reversing the Sign 240
The Numeric Data Processor 240
Key Points 242
Questions 243
14 ARITHMETIC：Ⅱ—PROCESSING ASCII AND BCD DATA 244
Introduction 244
Data in Decimal Format 245
Processing ASCII Data 246
Processing Unpacked BCD Data 249
Processing Packed BCD Data 251
Converting ASCII Data to Binary Format 253
Converting Binary Data to ASCII Format 255
Shifting and Rounding a Product 257
Program：Converting AsCu Data 257
Key Points 263
Questions 264
15 DEFINING AND PROCESSING TABLES 265
Introduction 265
Defining Tables 265
Direct Addressing of Table Entries 267
Searching a Table 271
The XLAT （Translate） Instruction 277
Program：Displaying Hex and ASCII Characters 278
Sorting Table Entries 280
Linked Lists 281
The TYPE，LENGTH，and SIZE Operators 286
Key Points 286
Questions 287
Part E Advanced Input/Output 289
16 DISK STORAGE Ⅰ ORGANIZATION 289
Introduction 289
Disk Characteristics 289
The Disk System Area and Data Area 292
The Boot Record 294
The Directory 294
The File Allocation Table 296
Exercise：Examining the FAT 299
Processing Files on Disk 302
Key Points 302
Questions 302
17 DISK STORAGE Ⅱ WRITING AND READING FILES 304
Introduction 304
ASCIIZ Strings 305
File Handles 305
Error Return Codes 305
File Pointers 306
Using File Handles to Create Disk Files 306
Using File Handles to Read Disk Files 311
Using File Handles for Random Processing 313
Program：Processing an AScu File 320
Absolute Disk I/O 324
Disk Services Using File Control Blocks 325
Key Points 330
Questions 330
18 DISK STORAGE Ⅲ.INT 21H FUNCTIONS FOR SUPPORTING DISKS AND FILES 332
Introduction 332
Operations Handling Disk Drives 333
Program：Reading Data from Sectors 342
Operations Handling the Directory and the FAT 345
Program：Displaying the Directory 346
Operations Handling Disk Files 348
Program：Selectively Deleting Files 353
Key Points 356
Questions 356
19 DISK STORAGE Ⅳ: INT 13H DISK FUNCTIONS 357
Introduction 357
BIOS Status Byte 358
Basic INT I3H Disk Operations 358
Program：Using INT I3H to Read Sectors 360
Other INT I3H Disk Operations 363
Key Points 368
Questions 368
20 FACILITIES FOR PRINTING 369
Introduction 369
Common Printer Control Characters 370
INT 2IH Function 40H：Print Characters 370
Program：Printing With Page Overflow and Headings 371
Program：Printing ASCII Files and Handling Tabs 374
INT 2IH Function O5H：Print Character 378
Special Printer Control Characters 379
INT I7H Functions for Printing 380
Key Points 381
Questions 381
21 OTHER INPUT/OUTPUT FACILITIES 383
Introduction 383
Mouse Features 383
Mouse Functions 384
Common INT 33H Operations 385
Program：Using the Mouse 391
Ports 394
String Input/Output 395
Generating Sound 397
Key Points 397
Questions 398
Part F Advanced Programming 400
22 DEFINING AND USING MACROS 400
Introduction 400
Two Simple Macro Definitions 401
Using Parameters in Macros 402
Macro Comments 403
Using a Macro Within a Macro Definition 405
The LOCAL Directive 407
Including Macros from a Library 407
Concatenation 410
Repetition Directives 410
Conditional Directives 412
Key Points 416
Questions 417
23 LINKING TO SUBPROGRAMS 419
Introduction 419
The SEGMENT Directive 420
Intrasegment Calls 421
Intersegment Calls 422
The EXTRN and PUBLIC Attributes 423
Using EXTRN and PUBLIC for an Entry Point 425
Defining the Code Segment as PUBLIC 427
Using Simplified Segment Directives 429
Defining Common Data as PUBLIC 430
Defining Data in Both Programs 431
Passing Parameters to a Subprogram 433
Linking Pascal with an Assembly Language Program 436
Linking C with an Assembly Language Program 440
Key Points 442
Questions 444
24 MEMORY MANAGEMENT 445
Introduction 445
The Main DOS Programs 445
The High-Memory Area 446
The Program Segment Prefix 447
Memory Blocks 452
Memory Allocation Strategy 455
The Program Loader 456
Allocating and Freeing Memory 462
Loading or Executing a Program Function 463
Program Overlays 464
Resident Programs 470
Key Points 475
Questions 476
Part G Reference Chapters 478
25 BIOS DATA AREAS AND PROGRAM INTERRUPTS 478
Introduction 478
The Boot Process 478
The BIOS Data Area 479
Interrupt Services 482
BIOS Interrupts 483
BIOS：DOS Interface 487
DOS Interrupts 487
INT 2IH Services 488
Key Points 494
Questions 495
26 OPERATORS AND DIRECTIVES 497
Introduction 497
Type Specifiers 497
Operators 498
Directives 504
27 THE PC INSTRUCTION SET 525
Introduction 525
Register Notation 526
The Addressing Mode Byte 526
Two-Byte Instructions 527
Three-Byte Instructions 528
Four-Byte Instructions 528
Instruction Set 529
APPENDIXES 557
A Conversion Between Hexadecimal and Decimal Numbers 557
B ASCII Character Codes 560
C Reserved Words 562
D Assembler and Link Options 564
E The DEBUG Program 572
F Keyboard Scan Codes and ASCII Codes 579
ANSWERS TO SELECTED QUESTIONS 583
INDEX 595