8051 Microcontroller: Internals, Instructions, Programming and Interfacing

For every PC there are at least 20 embedded systems, and the number is increasing. 8051 is one of the most widely used microcontrollers in embedded system design, and its internal architecture, instruction set and interfacing techniques are presented in this book through simple language, excellent graphical annotations and a large variety of solved examples. Spread across 26 chapters, this book starts with the internal architecture of 8051, and then explains all instructions with examples of applications. In-depth discussions on interrupt-handling features are followed by the techniques of interfacing 8051 with the external world through different types of motors, relays, sensors, ADC/DACs, memory devices, keyboards, displays, etc. As most of the embedded systems are battery-powered, power-saving schemes play a major role in considerations of these system designs. Hence, an entire chapter is devoted to explaining power management using 8051. One full-length design example explaining both hardware as well as software aspects of a home protection system using 8051 is presented as a case study. Discussions are concluded by a chapter on advanced microcontrollers such as the AVR. Cover......Page 1 8051 Microcontroller......Page 4 Copyright......Page 5 Contents......Page 8 Preface......Page 24 Acknowledgements......Page 26 Introduction......Page 27 Microprocessor-Based System......Page 28 General Architecture......Page 29 MCS-51 Family......Page 30 Comparison Between 8085 and MCS-51......Page 31 Power Management......Page 33 Plastic Quad Flat Pack......Page 34 Points to Remember......Page 35 Search for Answers......Page 36 Think and Solve......Page 37 External Features......Page 39 Pins and Signals......Page 40 Program Memory Organization......Page 42 Program Lock Bits......Page 43 Data Memory Organization......Page 44 Register Banks......Page 45 Bit-Addressable Area......Page 46 System Clock......Page 47 Reset......Page 48 Evaluate Yourself......Page 50 Think and Solve......Page 51 Sfr Map......Page 53 Sfr Functions......Page 54 Processor Status Word......Page 55 Accumulator......Page 56 Port Registers......Page 57 Architecture of Mcs-51 Ports......Page 58 Dc Characteristics of Mcs-51 Ports......Page 61 Power Management......Page 62 Summary......Page 63 Search for Answers......Page 64 Think and Solve......Page 65 Instructions and Instruction Groups of Mcs-51......Page 67 Addressing Modes......Page 68 Immediate Addressing Mode......Page 69 Register Direct Addressing Mode......Page 70 Register Indirect Addressing Mode......Page 71 Forms of Mov Instruction......Page 72 16-Bit Data Load......Page 73 Format of Mov Instruction......Page 74 Operand Expressions......Page 75 Solved Examples......Page 76 Evaluate Yourself......Page 79 Search for Answers......Page 81 Think and Solve......Page 80 Introduction......Page 83 Add Instruction......Page 84 Addc Instruction......Page 86 Subb Instruction......Page 88 Inc Instruction......Page 89 Dec Instruction......Page 90 Evaluate Yourself......Page 91 Think and Solve......Page 92 Program Branching Instructions......Page 93 Ljmp Instruction......Page 94 Ajmp Instruction......Page 95 Sjmp Instruction......Page 96 Application of Ajmp and Sjmp......Page 97 Conditional Branching......Page 98 Jnz Instruction......Page 99 Cjne Instruction......Page 100 Djnz Instruction......Page 101 Labels in Program Listing......Page 102 Solved Examples......Page 103 Points to Remember......Page 104 Search for Answers......Page 105 Think and Solve......Page 106 Copy Block......Page 107 Shift Block......Page 109 Count No. of Nulls......Page 110 Find Checksum......Page 112 Sum of Natural Numbers......Page 113 Sum of a Series......Page 114 Fibonacci Series......Page 116 Generate a Series......Page 117 Evaluate Yourself......Page 119 Think and Solve......Page 120 Need of Subroutines......Page 121 Lcall Instruction......Page 122 Ret Instruction......Page 123 Mechanism of Subroutines......Page 124 Nesting of Subroutines......Page 125 Push Instruction......Page 126 Pop Instruction......Page 127 Comparison with 8085......Page 128 Solved Examples......Page 129 Points to Remember......Page 132 Evaluate Yourself......Page 133 Think and Solve......Page 134 Introduction......Page 135 ANL Instruction......Page 136 ORL Instruction......Page 138 XRL Instruction......Page 139 CPL Instruction......Page 140 RL Instruction......Page 141 RRC Instruction......Page 142 Solved Examples......Page 143 Evaluate Yourself......Page 146 Think and Solve......Page 147 Introduction......Page 149 Boolean Data Loading and Movement......Page 150 Setb Instruction......Page 151 Mov Instruction......Page 153 Jc Instruction......Page 155 Jnc Instruction......Page 156 Jb Instruction......Page 157 Jnb Instruction......Page 158 Anl Instruction......Page 159 Orl Instruction......Page 160 Cpl Instruction......Page 161 Solved Examples......Page 163 Evaluate Yourself......Page 164 Think and Solve......Page 165 Count 1s in a Byte......Page 167 Unpack a Bcd Number......Page 169 Pack Array of Unpacked Bcd Digits......Page 170 Find Largest and Smallest Integers of an Array......Page 172 Bubble Sorting......Page 174 Find the Sum of Factorials......Page 177 Sort Out Numbers Divisible by 4......Page 179 Points to Remember......Page 180 Search for Answers......Page 181 Think and Solve......Page 182 Introduction......Page 183 Movc Instruction......Page 184 Movx Instruction......Page 185 Xch Instruction......Page 188 Xchd Instruction......Page 190 Mul Instruction......Page 191 Div Instruction......Page 192 Da a Instruction......Page 193 Swap Instruction......Page 195 Solved Examples......Page 196 Review Questions......Page 198 Think and Solve......Page 199 Compare with External Array......Page 201 Find Sum of a Series......Page 202 Reverse an Array......Page 204 Hex to Bcd Conversion......Page 205 Update Clock Display......Page 206 Display Shift for Right Entry......Page 207 Count Number of Words......Page 209 Generate Prime Numbers......Page 211 Evaluate Yourself......Page 214 Think and Solve......Page 215 What is an Interrupt?......Page 217 External Interrupts of 8051......Page 218 Tcon......Page 219 Ie......Page 221 Checklist for Into......Page 222 Benefits of Interrupt......Page 223 Solved Examples......Page 224 Evaluate Yourself......Page 228 Think and Solve......Page 229 Differences Between a Timer and a Counter......Page 231 8051/52 Timers......Page 233 Introduction......Page 234 Overview of Serial Communication......Page 235 Serial Data Format......Page 236 Sbuf......Page 237 Scon......Page 238 Pcon......Page 239 Mode 0......Page 240 Multiprocessor Communication......Page 241 Role of Timer in Baud-Rate Generation......Page 242 Why 11.0592 MHz?......Page 243 Initialization Steps for Serial Communication......Page 244 Solved Examples......Page 245 Summary......Page 247 Search for Answers......Page 248 Think and Solve......Page 249 Need of External Memory......Page 250 Interfacing Signals......Page 251 Program Memory Interfacing......Page 252 Data Memory Interfacing......Page 253 Three Lock Bits......Page 255 Solved Example......Page 256 Evaluate Yourself......Page 257 Think and Solve......Page 258 Introduction......Page 260 Example 18.1......Page 261 Bouncing of Keys......Page 262 Software Debouncing......Page 263 Key Matrix......Page 264 Scanning Keyboard Matrix......Page 265 Debouncing Keyboard Matrix......Page 267 Evaluate Yourself......Page 270 Think and Solve......Page 271 Led Interfacing......Page 272 Solved Examples......Page 274 Seven-Segment Display Interfacing......Page 275 Multiplexed Display......Page 276 Summary......Page 280 Search for Answers......Page 281 Think and Solve......Page 282 How a Dac Works......Page 284 Sample and Hold......Page 285 Interfacing Dac......Page 286 Interfacing Adc......Page 287 Solved Examples......Page 289 Evaluate Yourself......Page 294 Think and Solve......Page 295 How Dc Motor Works......Page 296 Direction Control......Page 297 H-Bridge Using Transistors......Page 298 L293D......Page 299 Changing Duty Cycle of Square Wave......Page 300 Relay and Optocoupler......Page 301 Solved Examples......Page 302 Search for Answers......Page 306 Think and Solve......Page 307 Full-Step Rotation......Page 308 How Step Angle is Controlled......Page 309 Generation of 3.6° Step Angle......Page 310 Stepper Motor Interfacing......Page 311 Direction Control......Page 313 Speed Control......Page 315 Solved Examples......Page 316 Evaluate Yourself......Page 318 Think and Solve......Page 319 Introduction......Page 320 How a Servomotor Works......Page 321 For Pulses of 2 Milliseconds......Page 323 For Pulses of 1.5 Milliseconds......Page 324 Home-Position Detection......Page 325 Solved Example......Page 326 Summary......Page 329 Search for Answers......Page 330 Think and Solve......Page 331 Power-Saving Modes......Page 332 Idle Mode......Page 333 Power-Down Mode......Page 334 Diff erence Between Idle and Power-Down Modes......Page 335 A Case Study on Power Management......Page 336 Case 1: Normal Design Without Power Management......Page 337 Case 2: Power Management Using Idle Mode......Page 340 Case 3: Power Management Using Power-Down Mode......Page 341 Further Improvements......Page 343 Evaluate Yourself......Page 344 Think and Solve......Page 345 What is Home Protection System?......Page 346 Overall System......Page 347 Display Drivers......Page 348 Sensor Interfacing......Page 349 Ir-Sensing Module......Page 350 Timer 0 Interrupt Service Routine......Page 351 Display Refreshing......Page 352 Software Listing......Page 353 Evaluate Yourself......Page 360 Think and Solve......Page 361 Avr Microcontrollers......Page 362 Important Features......Page 363 Internal Architecture......Page 364 Program Memory......Page 365 Status Register......Page 366 Power Management and Sleep Modes......Page 367 Atmega8 Instruction Set......Page 368 Comparison Between Atmega8 and Atmega16......Page 371 Pins and Signals......Page 372 Internal Architecture......Page 373 Instruction Set......Page 375 ARM Core Architecture......Page 380 Important Features......Page 381 Renesas Microcontrollers......Page 383 Evaluate Yourself......Page 384 Think and Solve......Page 385 Answers For Evaluate Yourself......Page 386 Arithmetic Operations......Page 388 Logical Operations......Page 390 Data Movement Operation......Page 391 Boolean Variable Operations......Page 392 Call and Jump Operations......Page 393 Instructions Arranged by their Opcodes......Page 394 Instructions Arranged by Alphabetical Order......Page 400 Instructions with Direct Addressing......Page 405 Instructions with Indirect Addressing Through Ro......Page 406 Instructions with Register Addressing Through Ro......Page 407 Instructions with Register Addressing Through R2......Page 408 Instructions with Register Addressing Through R5......Page 409 Instructions with Register Addressing Through R7......Page 410 Instructions with Register Addressing Through the Accumulator......Page 411 8051 Programs Using C......Page 414 Mcs®-51 Programmer’s Guide and Instruction Setinstruction Definitions......Page 420 Bibliography......Page 468 Index......Page 470