Book delves into serial ports; they never were “obsolete”

A recently published book addresses the need for and popularity of serial ports. Serial Port Complete Second Edition (Lakeview Research, December 2007, ISBN 978-1931448-06-2) by Jan Axelson explores hardware and software; ports in PCs and embedded systems; and RS-232, RS-485, and wireless interfaces. Axelson banishes the myth that serial ports are obsolete. She describes how, when the USB interface took hold in the late 1990s, many in the industry made this prediction. Although plenty of peripherals that formerly used the serial port have switched to USB, some devices can’t use USB or have requirements that USB alone can’t provide. As a result, many embedded systems use serial ports because they’re inexpensive and less complex to program than USB ports and can use longer cables than USB allows. Also, the RS-485 serial interface supports networks for many monitoring-and-control applications. Although most PCs no longer have built-in serial ports, you can easily add them with USB converters, meaning that the number of expansion slots no longer limits the number of serial ports a system can have. Microsoft’s .NET Framework SerialPort class lists a large number of ports, indicating that PC applications continue to find communication ports useful.

The first chapters focus on hardware and interfacing and introduce asynchronous-serial communications. Chapter 3 discusses serial ports in PCs, and chapters 4 through 8 provide a guide to interfacing using RS-232, RS-485, and wireless technologies. The following chapters provide a guide to programming. Axelson also describes how to program serial ports on PCs using Visual Basic .NET and Visual C# .NET. Later, she 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. The $39.95, 380-pg book also covers hardware and programming for RS-485 serial networks and how to implement USB virtual-communication ports using special-purpose and generic USB controllers.

For the second edition, the author has revised and updated the contents. For example, she adds code in C/C# as well as in Basic and includes code examples for PCs and embedded systems. The book also covers designing and programming USB virtual-communication ports, using wireless technologies to transmit serial data, accessing serial ports over Ethernet or Wi-Fi networks, and transferring text data using Unicode encoding. Whether your interest is hardware or software and whether you work with PCs, embedded systems, or both, you’ll find useful guidance in this book. Programmers will learn how to communicate using serial ports, including USB virtual-communication ports, in PCs and embedded systems. The sample code for PCs and microcontrollers in Basic and C/C# provides a quick start for a variety of applications. Circuit designers will find designs for a variety of applications, including converters that translate between RS-232, RS-485, and 3 and 5V logic. The book also includes designs with fail-safe features, high noise immunity, and low power consumption.

The book provides hobbyists and experimenters with inspiration for projects and enables teachers and students to learn about serial ports and use the examples in this book to demonstrate concepts. This book assumes a basic knowledge of electronics and either Basic/Visual Basic or C/C# programming. It assumes no previous knowledge or experience with serial-port hardware or programming.