Hitachi, Ltd.

Toshitaka Hara

Nagaharu Hamada

Yukitaka Hayashi

Masahiro Iwamura

Yoji Nishio

Tadaaki Bandoh

Nobuo Sato

Yoshiki Kobayashi

Kazuhiro Fujisaki

Norio Murayama

Yasuo Minowa

Mitsuo Kikkawa

When a user of a data base desires to fetch necessary information from the data base, display the fetched information on a display unit and save a part of the data displayed on the screen of the display unit, partial data on the display screen is extracted on the basis of two kinds of tables, a character string table and a range table. The character string table is for defining a character string used as a key to search for the data on the display screen. When a character string is found on the display screen, the range table is applied to determine a data region to be extracted inclusive of this character string. The character string used as a key to search and the extracting data region which are defined in advance on the respective tables simplify the operation by the user.

Method and apparatus for system for selectively extracting display data

A cathode ray tube having a viewing screen on which time points represented by a plurality of points spaced from one another with a predetermined time interval are displayed in the raster direction, while display quantities of trend graphs are displayed as functions of the time points in the direction perpendicular to the raster direction by a plurality of points spaced from one another with a predetermined interval. A raster scanning is effected by sweeping the viewing screen with a scanning point whereby the scanning lines thus produced are correlated to the spaced points representing the display quantities. Apparatus stores the display quantities of the trend graph corresponding to the time points, sequentially reads out the display quantities from the memory apparatus in the order of the time points, and compares the display quantities read out from the memory apparatus with a display quantity represented by an instant scan line. The comparison apparatus compares the display quantity read out corresponding to an instant time point and an instant position of the scanning spot of the instant scan line with a display quantity represented by an instant scan line, supplies a video signal to the cathode ray tube when the instant display quantity represented by the instant scan lines lies in a range delimited by the display quantity at the instant time point and the display quantity at the select one time point of the time points immediately preceding and following the instant time point.

Trend graph display system

A display system for displaying information in response to an input video signal comprises a data control unit including a microprocessor and a microprogram memory for storing a program for the microprocessor, a refresh memory unit connected to the data control unit through an address bus and a data bus, and a video control unit for accessing display data stored in the refresh memory unit by a timing control unit to produce a video signal. The refresh memory unit comprises memories sectioned by byte, an I/O controller which receives a read/write control signal to indicate whether the access by the data control unit is read access or write access and an access memory specifying signal to indicate whether it is a one-byte memory access or a two-byte memory access to produce an I/O control signal, and a memory controller responsive to the I/O control signal to control data access to the two byte memories.

Microprocessor controlled display system

A graph display apparatus using a CRT display unit of raster scanning type for displaying a graph with a high accuracy, that is, a high resolution. The apparatus comprises a raster counter for counting the number of rasters to identify the raster number of the scanning lines presently scanning the display screen of the CRT display unit, and a plurality of graph display units for displaying a graph with a standard accuracy. Each graph display unit comprises a memory having a capacity corresponding to the number of time points obtained by dividing the time axis extending in the scanning direction of the raster on the display screen by the number n of data plotting for storing the raster numbers corresponding to the levels of the quantities to be displayed at the individual time points, and a comparator comparing the output of the raster counter with the output of the memory read out sequentially in timing relation with the individual time points for providing a coincidence detection signal only when coincidence is reached between the output of the counter and the output of the memory at a time point. The display signal outputs of these graph display units are combined to display a graph with a desired resolution which is for example two or four times the standard resolution. To this end, a variable accuracy circuit is associated with each of the graph display units to receive the output of the associated graph display unit thereby providing a display signal output at the timing of scanning specific dots among a plurality of dots corresponding to one time point. The outputs of the variable accuracy circuits are applied to an OR circuit which applies an output signal representing the logical sum of these inputs to the CRT display unit.

Variable accuracy trend graph display apparatus

A data display control system for displaying respective data memorized in a plurality of refresh memories which is operable in various display modes including a selective picture display, a superimposed picture display and a shifting picture display. Individual data memorized in respective refresh memories contain each a display control bit adapted to determine whether or not the individual data are to be displayed on the screen. The data display control system reads out from the respective refresh memories a data information to be picture-displayed and only when the contents of a display control bit contained in the data information designate a display, it converts this data information into a video signal for a picture display. The contents of the display control bit are changeable for individual data.

Data display control system with plural refresh memories

A computer system comprises a central processor unit, a single memory apparatus and an external processor unit which is adapted to read out N bytes of data in each period of T.sub.o. The number n of data remaining to be processed after a time elapse T.sub.1 (T.sub.1 &lt; T.sub.o) from the beginning of the period T.sub.o is successively compared with the number m of data which can be read out continuously by the external processor unit during a remaining time span (T.sub.o -T.sub.1). So long as the number n is smaller than the number m the external processor unit is allowed to read out the data from the memory apparatus only when the central processor unit is not using the memory apparatus. On the other hand, when the number n becomes equal to the number m, connection between the memory apparatus and the central unit is interrupted to allow in turn the external processor unit to read out data from the memory apparatus, whereby the processing efficiency of the computer system is improved.

Computer systems having a common memory shared between a central

A system for controlling display of characters on partitioned regions of a CRT display surface comprising a refresh memory having a capacity enough to store application display data for exhibiting application display on the entire area of the CRT display surface, and a special display data memory storing special display data for exhibiting special display on a limited specific region, for example, the lowest and second lowest display line portions of the CRT display surface to be pointed by a light pen. In the system, elements including a data selector, a comparator, a register and a flip-flop are provided to switch over the data input to the CRT unit so that, when the special display is not required, the data stored in the refresh memory are solely read out to exhibit the application display on the entire area of the CRT display surface, while when the special display is required, the data stored in the special display data memory are read out to exhibit the special display on the specific display region during scanning of this specific display region of the CRT display surface.

Partitioned display control system

A raster scan type CRT display system is disclosed which has a randomly accessable refresh memory. The display system comprises column and row start address registers for defining a read start address for the refresh memory, column and row address counters for counting the contents of the column and row start address registers as start positions to generate a read address of the refresh memory for display, column and row cursor registors for defining a data entry position on a CRT screen, and column and row address generators for generating an entry address for the refresh memory based on the contents of the column and row start address registers and the contents of the column and row cursor registers, whereby a rolling or shifting of the image is effected and the refresh memory can be accessed by a processor for read/write operation without the need to monitor the image rolling.

Raster scan type CRT display system having an image rolling function

A bus-coupler or bus window in an information transport system for connecting a plurality of buses, to each of which a plurality of arithmetic units, a plurality of memory or storage units and a plurality of input-output units are connected separately through stations. The bus coupler includes a dead-lock control circuit for preventing a dead-lock which could possibly occur in communication between the buses.

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Hitachi, Japan

Toshitaka Hara