Serial Port Complete Second Edition - $39.95

by Jan Axelson This book explores wide and varied territory, including hardware and software; ports in PCs and in embedded systems; and RS-232, RS-485, and wireless interfaces. You don’t need to read the book straight through. If you’re interested in a particular topic, you can skip right to it. The first chapters focus on hardware and interfacing. Chapters 1 and 2 are an introduction to asynchronous serial communications. Chapter 3 discusses serial ports in PCs, and chapters 4–8 are a guide to interfacing using RS-232, RS-485, and wireless technologies. The next chapters are a guide to programming. Chapters 9 and 10 show how to program serial ports on PCs using Visual Basic .NET and Visual C# .NET. Chapter 11 shows how to program serial ports for embedded systems with examples for microEngineering Labs' PICBASIC PRO compiler and Microchip Technology's MPLAB C18 C compiler. Chapters 12 and 13 focus on hardware and programming for RS-485 serial networks. Chapters 14–16 explain how to implement USB virtual COM ports using special-purpose and generic USB controllers. 380 pages.

Table of Contents Introduction Acknowledgments 1 Options and Choices When to use a Serial Port Advantages Limits System Components The Computers The Physical Link Programming Applications Example Systems Managing Communications Special-purpose Modules 2 Formats and Protocols Sending Serial Data Asynchronous and Synchronous Communications Word Formats Bit Rate and Baud Rate System Support for Low-level Protocols Sending Bits The Format The Need for Accurate Timing Autodetecting the Bit Rate Autodetecting a COM Port Data Formats Binary Data Text Data ASCII Hex Application-specific Protocols Preventing Missed Data Flow Control Buffers Event-driven Programming and Polling Acknowledgments Error Checking 3 COM Ports on PCs Port Architecture Device Manager Port Resources Serial Servers Accessing Ports Drivers Identifying Ports GUIDs for COM Ports COM Port Numbering INF Files Options for Application Programming 4 Inside RS-232 The Hardware Interface Signals Voltages Timing Limits Converting Voltages Interface Chips Short-range Circuits Port-powered Circuits Using Outputs as a Power Source Regulating the Voltage Alternate Interfaces Direct Connection Other Unbalanced Interfaces 5 Designing RS-232 Links Connectors and Adapters Connector Options Adapters Using Microcontroller Development Boards Cables Length Limits Surge Protection Isolated Lines Ways to Achieve Isolation About Grounds Power Supply Grounds Optoisolating Debugging Tools Using a Breakout Box Monitoring with a Voltmeter Oscilloscopes and Logic Analyzers 6 Inside RS-485 About RS-485 Balanced and Unbalanced Lines Voltage Requirements Current and Power Speed Internal Protection Circuits Interfacing Options Chips Adding a Port on a PC Converting 3.3/5V Logic Converting RS-232 Controlling the Driver Enable Re-enabling the Driver Software-assisted Control Hardware Control 7 Designing RS-485 Links and Networks Long and Short Lines When Is a Line Long? Calculating Line Length Choosing a Driver Chip Line Terminations Characteristic Impedance Adding a Termination Effects of Terminations Reflections Series Terminations Terminations for Short Lines AC Terminations Network Topologies Biasing the Line Open-circuit Protection Short-circuit Protection Cable Types How a Wire Picks Up Noise Twisted-pair Cable Selecting Cable Grounds and Differential Lines Ensuring a Common Ground Isolated Lines Using Multiple Buses Adding a Repeater Implementing a Star Topology 8 Going Wireless Media and Modulation Using a Carrier Frequency Spread Spectrum Technology Ensuring Reliable Transfers Infrared Transmitters and Receivers IrDA Radio Frequency Complying with Regulations Choosing an RF Band Implementing a Link Using Other RF Standards 9 Using .NET’s SerialPort Class Gaining Access to a Port Finding Ports Opening a Port Timeouts Receive Threshold Closing a Port Transferring Data Transferring Bytes Transferring Text Using Stream Objects BinaryReader and BinaryWriter StreamReader and StreamWriter Saving a Port and Parameters The Application Settings Architecture Combo Box Example 10 Managing Ports and Transfers in .NET Receiving Data Setting Timeouts Detecting Received Data Collecting Received Data Ensuring Efficient Transfers Sending Data Avoiding Timeouts Sending without Blocking the Application Preventing Buffer Overflows Ensuring Efficient Transfers Flow Control Selecting a Method Monitoring and Controlling the Signals Handling Errors Exceptions The ErrorReceived Event Verifying Received Data Structuring an Application Defining a ComPorts Class Setting Parameters with Combo Boxes Defining Application-specific Events 11 Ports for Embedded Systems A Microcontroller Serial Port About the PIC18F4520 The Enhanced UART Registers Configuring and Accessing the Port Setting the Bit Rate Interrupts Basic Operations Accessing a Port Configuring the Port Sending Data Receiving Data Using Interrupts Using Flow Control Adding Ports Multiple On-chip UARTs Firmware UARTs External UARTs 12 Network Programming Managing Traffic Steps in Exchanging a Message Protocols Using Existing Protocols Debugging Tips Addressing Assigning Addresses Detecting Addresses Reserving Address Values Defining a Message Format 9-bit Format 13 An RS-485 Network Connecting the Nodes Transceivers Terminating and Biasing Cabling Example Protocol Addresses Message Format Commands Reading a Byte Writing a Byte Polling the Nodes Configuring the Driver-enable Line Sending Commands Responding to Polls Auxiliary Routines Decoding Received Data 14 Inside USB Hosts and Devices Assigning a Driver on the Host Requirements Host Responsibilities Device Responsibilities Speed Endpoints USB Transfers Transfer Types Transactions The Data Toggle 15 Using Special-function USB Controllers Inside the Chips Serial Interface (FT232R) Parallel Interface (FT245R) Prototyping Modules Using the Controllers Drivers Adding Vendor-specific Data Implementing a Virtual COM Port Converting from RS-232 to USB 16 Using Generic USB Controllers The Communication Devices Class Documentation Overview Device Controllers Host Drivers Using the Abstract Control Model POTS Models Virtual COM Ports Requests Notifications Maximizing Performance Descriptors and INF Files Device Descriptor Configuration Descriptor Communication Class Interface Descriptors Data Class Interface Descriptors String Descriptors The INF File Composite Devices Index