Terminal Tektronix

There are three Tektronix terminals that are emulated, the 4010, 4014 and 4027. The 4010 is a high resolution terminal with cross hair cursors for graphics input, the 4014 adds a hardware line patterns, choice of character sizes and user definable character sets with local storage for commonly used structures. The 4027 is a color raster terminal with 64 colors, 16 character fonts, as well as polygon and vector commands. 

EMU-TEK - Tektronix terminal emulator, hardware supported IBM PC, available from FTG Data Systems, 10801 Dale Street, Suite J-2, PO Box 615, Stanton, CA 90680, U.S.A. 

VersaTerm-PRO - Tektronix terminal emulator, hardware supported Apple Macintosh, available from Peripherals, Computers Supplies, Inc., 2457 Perkiomen Ave., Mt. Penn, PA 19606, U.S.A. 

Terminals tied to a computer through RS232C or 20 mA connections are an example of loosely coupled devices. The serial ASCII transmission of data is adequate for applications where dynamics or animation are not a factor (the VT125 and GIGI can be used to a only very limited extent here). This approach has been used in both classes of equipment, our own terminals for example in raster work and Tektronix or IMLAC terminals in vector systems. 

Tektronix equipment, and functioning for any terminal that has 4010 emulation. The cost of this system can run from as low as a few thousand dollars for some minimal capability to thirty thousand for a full blown software system. The features of this package include software libraries as well as interactive graphics and drawing routines. 

Pre-1980 —Flat File Storage of Chemical Structures. Computers consisted of mainframe machines (e.g., IBM 3090) and small minicomputers (Digital, Prime). Users connected through low speed serial connections, using "dumb" terminals (no graphics capability) or monochrome vector graphics terminals such as Tektronix and Imlac. Chemical structures were mainly stored as either (l)individ-ual structure files, indexed by name, and handled one or a few structures at a time or (2) in a flat-file database accessed by record number (26). A typical corporate database contained up to a few tens of thousands of structures. 

Molecular Manipulation and Superimposition. To facilitate molecular comparisons, a variety of computer graphic techniques are available for three-dimensional manipulation and display of the stored structures in the library file (12,13). In our laboratory lateral stereo pair views of either single line or ball and stick models are displayed on a Tektronix 4014 graphics terminal linked to a Univac 1100/42 computer. 

In addition MOLY contains a large number of utility programs which allow for efficient molecular storage, retrieval, orientation and display. The system is written entirely in FORTRAN and executes on an IBM 370/158 under the MVS operating system and the TSO time-sharing system. User interaction is via a Tektronix 4006 or 4010 graphics terminal. Hard copy capabilities are provided via Tektronix photocopiers as well as a Calcomp digital plotter. 

Detailed instructions for this modification to the operating system were already available to us through purchase of the PLOT-10 Terminal Control System software from Tektronix, Inc., for support of Tektronix 4010 series terminals on IBM computers. 

Figure 20. Negatively stained image and reconstructions of fiber of HbS (hemoglobin S). (a) Micrograph of fiber of HbS prepared from a sickled cell by direct lysis with negative stain on the electron microscope grid, (b) Two-dimensional reconstruction of the fiber of HbS using computer reconstruction techniques with the maxima from the Fourier transform. The output is recorded from a Tektronix graphics terminal, (c) Two-dimensional reconstruction as in (b), but with only the maxima of the layer lines 1-6 of the Fourier transform used. Reproduced from ref. 238 (Dykes et al., Nature 1978, 272, 506) with permission of Macmillan Magazines.

The output routine for the pH and TO data pairs Is a low-priority background program. The punched paper tape with the data Is input into a DEC Edusystem 50 computer which is programmed In BASIC to analyse the data and display them on a Tektronix 4010 terminal. A typical titration requires about 30 min, and the analysis of data another 5. 

To make the Macintosh compatible with MACCS, we use the Versaterm Pro software package, which allows the Macintosh to emulate the Tektronix 4105, one of the acceptable terminal types. By this same package, the Macintosh can emulate the Tektronix 4014 and VT-100, which allow the chemists to use other applications programs, such as SYNLIB for chemical reaction literature and of course, all the standard non-graphics applications such as electronic mail. 

Allow for the display of information from sources expecting a Tektronix 4010 terminal for display, i e, implement a Tektronix 4010 emulator Again, this was to be transparent to the user and to require no explicit action on the user s part to access this mode ... 

The next version of the structure editor system developed with few major changes in concept The terminal interface was created as a "dumb" terminal emulator with no special formatting capabilities A Tektronix 4010 emulator was created with the ability to emulate only the output features of the 4010 and none of the special input features, such as cross-hairs, since these were never to be used ... 

Another problem which was specific to our environment was our lack of ReGIS terminals. DECslide would operate only on ReGIS terminals (VT-240, VT-241, and compatibles). Unfortunately we already had a significant investment in Tektronix 401x and VT-640 emulation terminals since MACCS would not run on ReGIS terminals at the time we purchased our graphics devices. Therefore further evaluation of DECslide was suspended. 

ChemSketch is a software program developed in-house to draw chemical structures and to retrieve structures from MACCS. It is written in VAX C and will run on any of the VAX CPUs as long as they are running the VMS operating system. ChemSketch currently supports Tektronix 401x, VT-640, and VT-240 terminal emulation. 

A variety of terminals (e.g. Tektronix 4010, VT640) can be emulated on more than one microcomputer. 

A general drawback of MDARC is the dated technology of its user interface. Communication with the server is via dumb terminal emulation, using a mixture of tty or VT text terminal emulation, and Tektronix or VT graphics terminal emulation for the graphics display. This older technology limits the versatility of the system and substantially reduces its aesthetic effect. 

Output. Based on what is requested in Query Definition, and on what a user commands during Inquiry Execution, the output of a search can be directed to an alphanumeric terminal, to a Tektronix graphics terminal if structures are needed, to CAS system printers, to a transaction file (PTFC) for the Communications Processor to produce standard chemistry cards at CAS, or to two types of disk files a temporary browsing file (RESULTS) or a permanent SAVE file which can be accessed either sequentially through GET or as a search key in SSS. 

---