For a variety of reasons, it may not be practical to scrap existing apparatus. Automation of old devices is frequently a custom job. Maybe the desired instrumentation is not available commercially. It might involve a prototype design or an entirely new instrumental approach. Sometimes the market is so small that vendors cannot sell enough units to make the development worthwhile. In some cases, the available commercial systems are too general for the intended applications. This situation will be more likely to occur as the use of automated information processing increases. Although the data measurement techniques are general enough to be used over a wide range of applications, the data processing requirements are not. Data processing systems tailored to particular customer needs are going to become more prevalent. Laboratory Automation Using the IBM PC addresses the needs of those who want to interface laboratory equipment to a small computer. It is aimed specifically at IBM PC-XT and PC-AT computers as well as any of the various clones on the market. It is also applicable to the IBM PS/2 or other computers of similar architecture that can run the DOS operating system. It is a good choice. These computers are low cost, widely available, and already familiar to many analytical chemists. There are extensive hardware and software products available for them, including a large number of scientific programs. The book is enhanced with numerous example programs in the text, which are also found on a 5.25-in. floppy disk inside the back cover. The examples are written in BASIC and are compatible with version 2.0 or later of BASICA (TM) or with QuickBASIC (TM). The BASIC language is also a good choice for the book. BASIC is easy to learn and is quite suitable for projects of low to medium complexity. Many scientists already know BASIC. It is easy to debug and frequently yields a working program quicker than with other languages. BASIC is often the language of choice for interfacing projects. One problem for any book on lab automation is the wide variety of interfacing hardware available to the implementer. Although they all do basically the same thing, the details of operation of the different interface circuit cards are not the same. The authors chose the model DT2801 board from Data Translation as a general analog and digital I/O board and the GPIB (IEEE 488) board from National Instruments for high-speed parallel interface examples. The interfacing strategies discussed
are appropriate to most of the hardware on the market, but the programming details needed to accomplish the objectives will differ. Readers with different hardware will have to modify the example programs found in this book, which could significantly increase the burden for the novice. The book gives a good overview of laboratory interfacing, including both hardware and software issues. Digitalto-analog and analog-to-digital conversion is explained, along with analog signal processing, signal filtering, the use of timers and counters, asynchronous serial communications applications, and the IEEE-488 bus. There is an appropriate mixture of theory and practice, the latter illustrated by useful suggestions on cabling, shielding, and grounding techniques. On the software side, the book discusses data storage, plotting, screen displays, peak detection, and image processing. There is an overview of the role of local area networks in the laboratory. When and how to use assembly language subroutines is explained in a section on advanced techniques. This section also deals with interrupts and direct memory access. This book is written in a clear and comprehensible cause-and-effect style, and there appear to be no significant errors of fact. None of the topics are covered in extensive detail. The book is most useful to give an overview, bring different possibilities and options to the attention of the reader, and provide a starting point for more detailed studies. The treatment of electronic subjects is terse, and readers with little previous knowledge of operational amplifiers and digital electronics may find it difficult to understand. Those readers should keep one of the many "electronics for scientists" type textbooks available for supplemental reading. The book also assumes that the reader is already familiar with the DOS operating system and the BASIC programming language. Attempting to read this book without t h a t knowledge may prove difficult. Although more experienced readers may already know most of the material in this book, there are still parts that may be useful. The sections on noise reduction, peak detection, image processing, local area networks, interrupts, and DMA contain useful information even for the more experienced individual. This book deserves a place on your library shelf if you are engaged in or are contemplating the use of a PC-type computer in a laboratory experiment. It is a clear and comprehensible survey of hardware and software techniques used in instrument interfacing.
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Circle 32 for literature. Circle 33 for Sales Rep. ANALYTICAL CHEMISTRY, VOL. 62, NO. 11, JUNE 1, 1990 · 669 A
