Computers in the Laboratory
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Current P r a c t i c e a n d Future Trends
Large mainframe
α—c Broadband network
Gateway Workstations
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oo J o s e p h G . L i s c o u s k i , Editor Digital Equipment Corporation Spotlights the computer revolution with descriptions of state-of-the-art automation for the lab. Explores what is being done today and projects ar eas where the revolution is headed. Evaluates the use of robots for rou tine sample preparation and dis cusses the use of graphic displays to make information easier to under stand. Looks at analyzing information in data bases, modeling from experi mental data, and surviving the flood of data from modern chemical instru mentation. Shows how to effectively extract useful information from vol umes of data. Conveys the breadth of computer usage in chemistry and the gains to be made with their use. CONTENTS Robots and Robotics in the Lab · Gen eral Lab Data Management and Specific Lab Needs · Applying Database Man agement in the Analytical Chemistry Lab • Planning an Approach to Lab Automa tion · Network and Communications · Introduction to Graphics · Chemists and Computers in the Corps of Engineers · Computer Generation of Structure-Ef fect Relationships from Text Data Bases • Coping with the Information Explosion Provided by Modern Chemical Instrumentaion · The Universe is Stochastic and Nonlinear Based on a symposium sponsored by the Division of Computers in Chemistry of the American Chemical Society ACS Symposium Series No. 265 128 pages (1984) Clothbound LC 84-18518 ISBN 0-8412-0867-0 US & Canada $34.95 Export $41.95 Order from: American Chemical Society Distribution Office Dept. 14 1155 Sixteenth St., N.W. Washington, DC 20036 or CALL TOLL FREE 800-424-6747 and use your VISA, MasterCard or American Express credit card.
Laboratory computer
OO Baseband network
Section computer
Figure 6. N e t w o r k i n g p r o v i d e s a n o t h e r level of integration for the e l e c t r o n i c laboratory. Here, two broadband nets, with a bridge joining them, interconnect a number of workstations. A baseband link ties larger computers together. A gateway couples the two dissimilar networks
networked by the end of 1986. A dual baseband-broadband net intercon nects the larger host computers and microbased workstations, respectively. Word processing (Mass-11, Microsys tems Engineering) and data base man agement (micro- and mainframe Ora cle) are available to all scientists. The mailman. As workstations be come more prevalent, intercommuni cation will become the most important factor—and quite possibly the bottle neck that prevents the system from serving its users properly. Some type of high-speed LAN is required. A number of vendors—for example, Sytek, Ungerman-Bass, Corvus, Net work Systems, and Nestar—have re sponded. A LAN provides a conduit over which information can flow. It does not establish, per se, a protocol for message format. LANs have been lik ened to a postal service that delivers letters (Figure 6) but does not con strain what is in the envelope, either in form or language. All that is re quired is that a reasonable address be on the face of the envelope. Conven tion has established a form for the let ter inside, and a language common to sender and receiver must be used. Electronic communication also re quires a rigid format that must be ad hered to at both ends for effective communication (Figure 7). The letter. Data transmission is usually effected by one of two coding schemes (the language): The Ameri
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can Standard Code for Information Interchange (ASCII), a seven-bit code; or an IBM eight-bit code called EBCDIC. IBM mainframe connections may be binary synchronous (bisynch, or BSC). Advanced network require ments led to IBM System Network Architecture (SNA). Most other com panies use ASCII conventions and bi nary asynchronous (asynch) commu nication protocols. Fortunately, a number of vendors make ASCII/BSC, ASCII/SNA converters that can be in stalled in workstations. They work like voltage converters, in that their operation should be transparent to the user. Examples are Irma (Digital Communications) and Cleo (Phone 1). GM employs Forte 3270 converters for its IBM PCs and Avatar units for its DEC Rainbows. Many of these con verters emulate IBM 327X terminals. Unfortunately, today there are five major protocol choices for message ar chitecture (the letter's form): Xerox Network System (XNS), the U.S. De partment of Defense's Transmission Control Protocol/Internet Protocol (TCP/IP), IBM's SNA, DEC's Digital Network Architecture (DNA), and the open system implementation of the International Standards Organization (OSI/ISO). In addition, there are smaller, special-purpose protocols such as Microcom Network Protocol (MNP). For example, VisiCorp inte grates three protocols into its VisiON products: For point-to-point connec-
