Embedded microcomputer systems : real time interfacing / 2nd ed.

1 Microcomputer-Based Systems p. 1
1.1 Computer Architecture p. 2
1.2 Embedded Computer Systems p. 6
1.3 The Design Process p. 10
1.3.1 Top-Down Design p. 10
1.3.2 Bottom-Up Design p. 14
1.4 Digital Logic and Open Collector p. 15
1.5 Digital Representation of Numbers p. 20
1.5.1 Fundamentals p. 20
1.5.2 8-Bit Numbers p. 22
1.5.3 Character Information p. 23
1.5.4 16-Bit Numbers p. 23
1.5.5 Fixed-Point Numbers p. 25
1.6 Common Architecture of the 6811 and the 6812 p. 27
1.6.1 Registers p. 28
1.6.2 Terminology p. 29
1.6.3 Addressing Modes p. 30
1.6.4 Numbering Scheme Used by Freescale for the 6811 and the 6812 p. 33
1.7 6811 Architecture p. 33
1.7.1 6811 Family p. 33
1.7.2 MC68HC711E9 p. 35
1.7.3 MC68HC11D3 p. 37
1.8 6812 Architecture p. 37
1.8.1 6812 Family p. 37
1.8.2 MC9C12C32 p. 38
1.8.3 MC68HC812A4 p. 41
1.8.4 MC68HC912B32 p. 42
1.9 Parallel I/O Ports p. 43
1.9.1 Basic Concepts of Input and Output Ports p. 43
1.9.2 Introduction to I/O Programming and the Direction Register p. 46
1.9.3 Our First Design Problem p. 47
1.10 Choosing a Microcontroller p. 53
1.11 Exercises p. 54
1.12 Lab Assignments p. 56
2 Design of Software Systems p. 58
2.1 Quality Programming p. 58
2.1.1 Quantitative Performance Measurements p. 59
2.1.2 Qualitative Performance Measurements p. 59
2.2 Assembly Language Programming p. 60
2.2.1 Introduction p. 60
2.2.2 Assembly Language Syntax p. 62
2.2.3 Memory and Register Transfer Operations p. 64
2.2.4 Indexed Addressing Mode p. 66
2.2.5 Arithmetic Operations p. 69
2.2.6 Extended Precision Arithmetic Instructions on the 6812 p. 74
2.2.7 Shift Operations p. 75
2.2.8 Logical Operations p. 77
2.2.9 Subroutines and the Stack p. 78
2.2.10 Branch Operations p. 82
2.2.11 Assembler Pseudo-ops p. 84
2.2.12 Memory Allocation p. 88
2.3 Self-Documenting Code p. 91
2.3.1 Comments p. 91
2.3.2 Naming Convention p. 94
2.4 Abstraction p. 95
2.4.1 Definitions p. 95
2.4.2 6811 Timer Details p. 96
2.4.3 6812 Timer Details p. 96
2.4.4 Time Delay Software Using the Built-in Timer p. 97
2.4.5 Moore Finite State Machine Traffic Light Controller p. 98
2.4.6 Mealy Finite State Machine Robot Controller p. 101
2.5 Modular Software Development p. 104
2.5.1 Local Variables in Assembly Language p. 104
2.5.2 Modules p. 109
2.5.3 Dividing a Software Task into Modules p. 113
2.5.4 Rules for Developing Modular Software in Assembly Language p. 116
2.6 Layered Software Systems p. 118
2.7 Device Drivers p. 119
2.7.1 Basic Concept of Device Drivers p. 119
2.7.2 Design of a Serial Communications Interface (SCI) Device Driver p. 121
2.8 Object-Oriented Interfacing p. 122
2.8.1 Encapsulated Objects Using Standard C p. 122
2.8.2 Object-Oriented Interfacing Using C++ p. 123
2.8.3 Portability Using Standard C and C++ p. 124
2.9 Threads p. 126
2.9.1 Single-Threaded Execution p. 126
2.9.2 Multithreading and Reentrancy p. 126
2.10 Recursion p. 128
2.11 Debugging Strategies p. 128
2.11.1 Debugging Tools p. 128
2.11.2 Debugging Theory p. 129
2.11.3 Functional Debugging p. 131
2.11.4 Performance Debugging p. 133
2.11.5 Profiling p. 136
2.12 Exercises p. 137
2.13 Lab Assignments p. 141
3 Interfacing Methods p. 142
3.1 Introduction p. 142
3.1.1 Performance Measures p. 142
3.1.2 Synchronizing the Software with the State of the I/O p. 143
3.1.3 Variety of Available I/O Ports p. 146
3.2 Handshake protocols p. 148
3.2.1 6811 Handshake Protocol p. 148
3.2.2 MC68HC812A4 Key Wakeup Interrupts p. 149
3.2.3 MC9S12C32 Key Wakeup Interrupts p. 150
3.3 Blind Cycle Counting Synchronization p. 151
3.3.1 Blind Cycle Printer Interface p. 151
3.3.2 Blind Cycle ADC Interface p. 152
3.4 Gadfly or Busy Waiting Synchronization p. 153
3.5 Parallel I/O Interface Examples p. 155
3.5.1 Blind Cycle Printer Interface p. 156
3.5.2 Blind Cycle ADC Interface p. 157
3.5.3 Gadfly Keyboard Interface Using Latched Input p. 158
3.5.4 Gadfly ADC Interface Using Simple Input p. 159
3.5.5 Gadfly External Sensor Interface Using Input Handshake p. 161
3.5.6 Gadfly Printer Interface Using Output Handshake p. 163
3.5.7 Gadfly Synchronous Serial Interface to a Temperature Sensor p. 164
3.6 Serial Communications Interface (SCI) Device Driver p. 173
3.6.1 Transmitting in Asynchronous Mode p. 174
3.6.2 Receiving in Asynchronous Mode p. 175
3.6.3 6811 SCI Details p. 177
3.6.4 6812 SCI Details p. 178
3.6.5 SCI Device Driver p. 179
3.7 Exercises p. 181
3.8 Lab Assignments p. 187
4 Interrupt Synchronization p. 189
4.1 What Are Interrupts? p. 190
4.1.1 Interrupt Definition p. 190
4.1.2 Interrupt Service Routines p. 191
4.1.3 When to Use Interrupts p. 192
4.1.4 Interthread Communication p. 192
4.2 Reentrant Programming p. 197
4.3 First-In-First-Out Queue p. 204
4.3.1 Introduction to FIFOs p. 204
4.3.2 Two-Pointer FIFO Implementation p. 205
4.3.3 Two-Pointer/Counter FIFO Implementation p. 208
4.3.4 FIFO Dynamics p. 209
4.4 General Features of Interrupts on the 6811/6812 p. 210
4.4.1 6811 Interrupts p. 212
4.4.2 6812 Interrupts p. 213
4.5 Interrupt Vectors and Priority p. 214
4.5.1 MC68H11E Interrupt Vectors and Priority p. 214
4.5.2 MC68HC812A4 Interrupt Vectors and Priority p. 216
4.5.3 MC68HC912B32 Interrupt Vectors and Priority p. 217
4.5.4 MC9S12C32 Interrupt Vectors and Priority p. 218
4.6 External Interrupt Design Approach p. 219
4.7 Polled Versus Vectored Interrupts p. 221
4.8 Keyboard Interface Using Interrupts p. 223
4.9 Printer Interface Using IRQ Interrupts p. 226
4.10 Power System Interface Using XIRQ Synchronization p. 229
4.11 Interrupt Polling Using Linked Lists p. 231
4.11.1 6811 Interrupt Polling Using Linked Lists p. 232
4.11.2 6812 Interrupt Polling Using Linked Lists p. 234
4.12 Fixed Priority Implemented Using One Interrupt Line p. 235
4.13 Fixed Priority Implemented Using XIRQ p. 237
4.14 Round-Robin Polling p. 238
4.15 Periodic Polling p. 238
4.15.1 MC68HC711E9 Periodic Interrupts p. 240
4.15.2 MC68HC812A4 Periodic Interrupts p. 243
4.15.3 MC9S12C32 Periodic Interrupts p. 245
4.16 Exercises p. 249
4.17 Lab Assignments p. 254
5 Threads p. 255
5.1 Multithreaded Preemptive Scheduler p. 256
5.1.1 Round-Robin Scheduler p. 257
5.1.2 Other Scheduling Algorithms p. 262
5.1.3 Dynamic Allocation of Threads p. 262
5.2 Semaphores p. 262
5.2.1 Spin-Lock Semaphore Implementation p. 263
5.2.2 Blocking Semaphore Implementation p. 265
5.3 Applications of Semaphores p. 267
5.3.1 Thread Synchronization or Rendezvous p. 268
5.3.2 Resource Sharing, Nonreentrant Code or Mutual Exclusion p. 268
5.3.3 Thread Communication Between Two Threads Using a Mailbox p. 268
5.3.4 Thread Communication Between Many Threads Using a FIFO Queue p. 268
5.4 Fixed Scheduling p. 269
5.5 Exercises p. 274
5.6 Lab Assignments p. 275
6 Timing Generation and Measurements p. 276
6.1 Input Capture p. 276
6.1.1 Basic Principles of Input Capture p. 276
6.1.2 Input Capture Details p. 277
6.1.3 Real Time Interrupt Using an Input Capture p. 281
6.1.4 Period Measurement p. 283
6.1.5 Pulse-Width Measurement p. 288
6.2 Output Compare p. 294
6.2.1 General Concepts p. 294
6.2.2 Output Compare Details p. 295
6.2.3 Square-Wave Generation p. 298
6.2.4 Pulse-Width Modulation p. 301
6.2.5 Delayed Pulse Generation p. 303
6.3 Frequency Measurement p. 304
6.3.1 Frequency Measurement Concepts p. 304
6.3.2 Frequency Measurement with [Delta]f = 100Hz p. 305
6.4 Conversion Between Frequency and Period p. 306
6.4.1 Using Period Measurement to Calculate Frequency p. 306
6.4.2 Using Frequency Measurement to Calculate Period p. 307
6.5 Measurements Using Both Input Capture and Output Compare p. 307
6.5.1 Period Measurement with [Delta]p = 1 ms p. 307
6.5.2 Frequency Measurement with [Delta]f = 0.1Hz p. 309
6.6 Pulse Accumulator p. 311
6.6.1 MC68HC711 Pulse Accumulator Details p. 311
6.6.2 MC9S12C32 Pulse Accumulator Details p. 312
6.6.3 Frequency Measurement p. 313
6.6.4 Pulse-Width Measurement p. 314
6.7 Pulse-width Modulation on the MC9S12C32 p. 314
6.8 Exercises p. 318
6.9 Lab Assignments p. 323
7 Serial I/O Devices p. 326
7.1 Introduction and Definitions p. 326
7.2 RS232 Specifications p. 332
7.3 RS422/USB/RS423/RS485 Balanced Differential Lines p. 334
7.3.1 RS422 Output Specifications p. 337
7.3.2 RS422 Input Specifications p. 338
7.3.3 RS485 Half-Duplex Channel p. 338
7.4 Other Communication Protocols p. 339
7.4.1 Current Loop Channel p. 339
7.4.2 Introduction to Modems p. 339
7.4.3 Optical Channel p. 340
7.4.4 Digital Logic Channel p. 340
7.5 Serial Communications Interface p. 341
7.5.1 Transmitting in Asynchronous Mode p. 341
7.5.2 Receiving in Asynchronous Mode p. 343
7.5.3 MC68HC711E9 SCI Details p. 345
7.5.4 MC9S12C32 SCI Details p. 346
7.6 SCI Software Interfaces p. 349
7.6.1 Full Duplex Serial Channel p. 349
7.6.2 Use of Data Terminal Ready (DTR) to Interface a Printer p. 352
7.6.3 Use of XON/XOFF to Interface a Printer p. 354
7.7 Synchronous Transmission and Receiving Using the SPI p. 355
7.7.1 SPI Fundamentals p. 355
7.7.2 MC68HC711E9 SPI Details p. 358
7.7.3 MC9S12C32 SPI Details p. 359
7.7.6 SPI Applications p. 361
7.8 Exercises p. 368
7.9 Lab Assignments p. 370
8 Parallel Port Interfaces p. 375
8.1 Input Switches and Keyboards p. 375
8.1.1 Interfacing a Switch to the Computer p. 375
8.1.2 Hardware Debouncing Using a Capacitor p. 377
8.1.3 Software Debouncing p. 381
8.1.4 Basic Approaches to Interfacing Multiple Keys p. 386
8.1.5 Sixteen-Key Electronic Piano p. 389
8.1.6 4 by 4 Scanned Keyboard p. 393
8.1.7 Multiplexed/Demultiplexed Scanned Keyboard p. 396
8.2 Output LEDs p. 398
8.2.1 Single LED Interface p. 400
8.2.2 Seven-Segment LED Interfaces p. 402
8.2.3 Scanned Seven-Segment LED Interface p. 402
8.2.4 Scanned LED Interface Using the 7447 Seven-Segment Decoder p. 405
8.2.5 Integrated LED Interface Using the MC14489 Display Driver p. 408
8.3 Liquid Crystal Displays p. 410
8.3.1 LCD Fundamentals p. 410
8.3.2 Simple LCD Interface with the MC14543 p. 412
8.3.3 Scanned LCD Interface with the MC145000, MC145001 p. 414
8.3.4 Parallel Port LCD Interface with the HD44780 Controller p. 416
8.4 Transistors Used for Computer-Controlled Current Switches p. 419
8.5 Computer-Controlled Relays, Solenoids, and DC Motors p. 421
8.5.1 Introduction to Relays p. 421
8.5.2 Electromagnetic Relay Basics p. 422
8.5.3 Reed Relays p. 424
8.5.4 Solenoids p. 424
8.5.5 Pulse-Width Modulated DC Motors p. 424
8.5.6 Interfacing EM Relays, Solenoids, and DC Motors p. 425
8.5.7 Solid-State Relays p. 430
8.6 Stepper Motors p. 431
8.6.1 Stepper Motor Example p. 431
8.6.2 Basic Operation p. 434
8.6.3 Stepper Motor Hardware Interfaces p. 438
8.6.4 Stepper Motor Shaft Encoder p. 441
8.7 Exercises p. 443
8.8 Lab Assignments p. 446
9 Memory Interfacing p. 448
9.1 Introduction p. 448
9.2 Address Decoding p. 451
9.2.1 Full-Address Decoding p. 452
9.2.2 Minimal-Cost Address Decoding p. 454
9.2.3 Special Cases When Address Decoding p. 457
9.2.4 Flexible Full-Address Decoder p. 458
9.2.5 Integrated Address Decoder on the MC68HC812A4 p. 459
9.3 Timing Syntax p. 461
9.3.1 Available and Required Time Intervals p. 461
9.3.2 Timing Diagrams p. 463
9.4 General Memory Bus Timing p. 463
9.4.1 Synchronous Bus Timing p. 464
9.4.2 Partially Asynchronous Bus Timing p. 465
9.4.3 Fully Asynchronous Bus Timing p. 466
9.5 External Bus Timing p. 468
9.5.1 Synchronized Versus Unsynch-ronized Signals p. 468
9.5.2 Freescale MC68HC11A8 External Bus Timing p. 469
9.5.3 Freescale MC68HC812A4 External Bus Timing p. 472
9.5.4 Freescale MC9S12C32 External Bus Timing p. 477
9.6 General Approach to Interfacing p. 483
9.6.1 Interfacing to a 6811 p. 483
9.6.2 Interfacing to a 6812 in Expanded Narrow Mode p. 484
9.6.3 Interfacing to a 6812 in Expanded Wide Mode p. 485
9.7 Memory Interface Examples p. 487
9.7.1 32K PROM Interface p. 487
9.7.2 8K RAM Interface p. 492
9.7.3 32K by 16-bit PROM Interface to a MC68HC812A4 p. 505
9.7.4 8K by 16-bit RAM Interface p. 507
9.7.5 Extended Address Data Page Interface to the MC68HC812A4 p. 509
9.7.6 Extended Address Program Page Interface to the MC68HC812A4 p. 511
9.8 Dynamic RAM (DRAM) p. 514
9.9 Exercises p. 514
9.10 Lab Assignments p. 523
10 High-Speed I/O Interfacing p. 524
10.1 The Need for Speed p. 524
10.2 High-Speed I/O Applications p. 525
10.2.1 Mass Storage p. 525
10.2.2 High-Speed Data Acquisition p. 526
10.2.3 Video Displays p. 527
10.2.4 High-Speed Signal Generation p. 527
10.2.5 Network Communications p. 527
10.3 General Approaches to High-Speed Interfaces p. 528
10.3.1 Hardware FIFO p. 528
10.3.2 Dual Port Memory p. 529
10.3.3 Bank-Switched Memory p. 529
10.4 Fundamental Approach to DMA p. 530
10.4.1 DMA Cycles p. 530
10.4.2 DMA Initiation p. 531
10.4.3 Burst Versus Cycle Steal DMA p. 531
10.4.4 Single-Address Versus Dual-Address DMA p. 532
10.4.5 DMA Programming p. 534
10.5 LCD Graphics p. 535
10.5.1 LCD Graphics Controller p. 535
10.5.2 Practical LCD Graphics Interface p. 538
10.6 Exercises p. 539
10.7 Lab Assignments p. 540
11 Analog Interfacing p. 541
11.1 Resistors and Capacitors p. 541
11.1.1 Resistors p. 541
11.1.2 Capacitors p. 542
11.2 Operational Amplifiers (Op Amps) p. 543
11.2.1 Op Amp Parameters p. 543
11.2.2 Threshold Detector p. 546
11.2.3 Simple Rules for Linear Op Amp Circuits p. 547
11.2.4 Linear Mode Op Amp Circuits p. 549
11.2.5 Instrumentation Amplifier p. 553
11.2.6 Current-to-Voltage Circuit p. 555
11.2.7 Voltage-to-Current Circuit p. 555
11.2.8 Integrator Circuit p. 555
11.2.9 Derivative Circuit p. 556
11.2.10 Voltage Comparators with Hysteresis p. 556
11.2.11 Analog Isolation p. 557
11.3 Analog Filters p. 558
11.3.1 Simple Active Filter p. 558
11.3.2 Butterworth Filters p. 559
11.3.3 Bandpass and Band-Reject Filters p. 560
11.4 Digital-to-Analog Converters p. 561
11.4.1 DAC Parameters p. 561
11.4.2 DAC Using a Summing Amplifier p. 563
11.4.3 Three-Bit DAC with an R-2R Ladder p. 564
11.4.4 Twelve-Bit DAC with a DAC8043 p. 566
11.4.5 DAC Selection p. 567
11.4.6 DAC Waveform Generation p. 570
11.5 Analog-to-Digital Converters p. 573
11.5.1 ADC Parameters p. 573
11.5.2 Two-Bit Flash ADC p. 574
11.5.3 Successive Approximation ADC p. 575
11.5.4 Sixteen-Bit Dual Slope ADC p. 576
11.5.5 Sigma Delta ADC p. 577
11.5.6 ADC Interface p. 578
11.6 Sample and Hold p. 579
11.7 BiFET Analog Multiplexer p. 580
11.8 ADC System p. 582
11.8.1 ADC Block Diagram p. 582
11.8.2 Power and Grounding for the ADC System p. 584
11.8.3 Input Protection for High-Speed CMOS Analog Inputs p. 584
11.9 Multiple-Access Circular Queue p. 585
11.10 Internal ADCs p. 587
11.10.1 6811 ADC System p. 587
11.10.2 6812 ADC System p. 589
11.10.3 ADC Software p. 591
11.11 Exercises p. 593
11.12 Lab Assignments p. 595
12 Data Acquisition Systems p. 597
12.1 Introduction p. 597
12.1.1 Accuracy p. 599
12.1.2 Resolution p. 601
12.1.3 Precision p. 601
12.1.4 Reproducibility or Repeatability p. 602
12.2 Transducers p. 602
12.2.1 Static Transducer Specifications p. 602
12.2.2 Dynamic Transducer Specifications p. 606
12.2.3 Nonlinear Transducers p. 607
12.2.4 Position Transducers p. 608
12.2.5 Velocity Measurements p. 609
12.2.6 Force Transducers p. 611
12.2.7 Temperature Transducers p. 612
12.3 DAS Design p. 617
12.3.1 Introduction and Definitions p. 617
12.3.2 Using Nyquist Theory to Determine Sampling Rate p. 618
12.3.3 How Many Bits Does One Need for the ADC? p. 621
12.3.4 Specifications for the Analog Signal Processing p. 621
12.3.5 How Fast Must the ADC Be? p. 626
12.3.6 Specifications for the S/H p. 626
12.4 Analysis of Noise p. 627
12.4.1 Thermal Noise p. 627
12.4.2 Shot Noise p. 630
12.4.3 1/f, or Pink Noise p. 630
12.4.4 Galvanic Noise p. 630
12.4.5 Motion Artifact p. 630
12.4.6 Electromagnetic Field Induction p. 631
12.4.7 Techniques to Measure Noise p. 631
12.4.8 Techniques to Reduce Noise p. 633
12.5 Data Acquisition Case Studies p. 635
12.5.1 Temperature Measurement p. 635
12.5.2 EKG Data Acquisition System p. 639
12.5.3 Position Measurement System p. 642
12.6 Exercises p. 643
12.7 Lab Assignments p. 650
13 Microcomputer-Based Control Systems p. 652
13.1 Introduction to Digital Control Systems p. 652
13.2 Open-Loop Control Systems p. 653
13.2.1 Open-Loop Control of a Toaster p. 654
13.2.2 Open-Loop Robotic Arm p. 654
13.3 Simple Closed-Loop Control Systems p. 659
13.3.1 Bang-Bang Temperature Control p. 659
13.3.2 Closed-Loop Position Control System Using Incremental Control p. 661
13.4 PID Controllers p. 663
13.4.1 General Approach to a PID Controller p. 663
13.4.2 Design Process for a PID Controller p. 666
13.4.3 Velocity PID Controller p. 668
13.4.4 Proportional-Integral Controller with a PWM actuator p. 669
13.5 Fuzzy Logic Control p. 672
13.5.1 DAC, ADC Fuzzy Controller p. 675
13.5.2 PWM Fuzzy Controller p. 681
13.5.3 Temperature Controller Using Fuzzy Logic p. 687
13.6 Exercises p. 691
13.7 Lab Assignments p. 694
14 Simple Networks p. 696
14.1 Introduction p. 696
14.2 Communication Systems Based on the SCI Serial Port p. 698
14.3 Design and Implementation of a Controller Area Network (CAN) p. 700
14.3.1 The Fundamentals of CAN p. 700
14.3.2 Details of the 9S12C32 CAN p. 703
14.3.3 9S12C32 CAN Device Driver p. 706
14.4 Inter-Integrated Circuit (I[superscript 2]C) Network p. 709
14.4.1 The Fundamentals of the I[superscript 2]C Network p. 709
14.4.2 I[superscript 2]C Synchronization p. 712
14.4.3 9S12 I[superscript 2]C Details p. 714
14.4.4 9S12 I[superscript 2]C Single Master Example p. 717
14.5 Modem Communications p. 718
14.5.1 FSK Modem p. 718
14.5.2 Phase-Encoded Modems p. 721
14.5.3 Quadrature Amplitude Modems p. 722
14.6 X-10 Protocol p. 723
14.7 Universal Serial Bus (USB) p. 730
14.7.1 Introduction p. 730
14.7.2 Modular USB Interface p. 734
14.7.3 Integrated USB Interface p. 735
14.8 Exercises p. 735
14.9 Lab Assignments p. 739
15 Digital Filters p. 742
15.1 Basic Principles p. 743
15.2 Simple Digital Filter Examples p. 745
15.3 Impulse Response p. 752
15.4 High-Q 60-Hz Digital Notch Filter p. 755
15.5 Effect of Latency on Digital Filters p. 760
15.6 High-Q Digital High-Pass Filters p. 762
15.7 Digital Low-Pass Filter p. 763
15.8 Direct-Form Implementations p. 765
15.9 Exercises p. 766
15.10 Lab Assignments p. 767
Appendix 1 p. 769
Appendix 2 p. 789
Index p. 802