A method of replicating changes made to databases distributed throughout a computer network is described. A first program (TP1) in the Collector node instructs a second program (TP2) in the Collectee node to send all updates to a database since the last conversation. TP2 processes queries to retrieve any changes made since the last conversation between the Collector and Collectee nodes and send the data to TP1, which updates the copy of the database on its own system.

A method for programming a computer system having a display console for displaying inages to control at least one of a virtual instrument and an instrument by the steps of displaying on the screen at least one first function-icon that references at least one first control module for controlling at least one first function; displaying on the screen at least one iteration-icon that references iteration control module for controlling multiple iterations of data flow displaying on the screen at leas...

A graphic terminal is disclosed using bitmaps to represent plural overlapping displays. Graphics software is also disclosed in which the overlapping asynchronous windows or layers are manipulated by manipulating the bitmaps. With this software, the physical screen becomes several logical screens (layers) all running simultaneously, any one of which may be interacted with at any time.

A data base system includes future versions of the data base which are maintained currently in response to orders for future execution. All transactions against the data base are time stamped to assure access to the proper version of the data base. Information concerning the various versions are stored as delta nodes or lists. The application of this data base system to the assignment of outside plant telephone facilities to telephone subscribers is also described.

A portable electrocardiogram storing apparatus has an electrocardiogram amplifier, an A/D converter for sampling the amplifier output and converting it into a digital signal, a patient actuatable switch, a plurality of electrocardiogram memories, and means for selecting one of the memories for storing the digital signal when the switch is actuated. A time memory is also provided for storing a time when the apparatus is set, and a timer measures a lapse time after the setting. A selected electroc...

A memory protection arrangement comprises a controller, a memory, first and second memory address self-hold circuits, first and second address comparators and a memory write signal controlling gate. The controlling gate is responsive to the output signal of the second comparator to control memory write such that a current address falling within a range between memory addresses of the first and second memory address self-hold circuits inhibits the memory from being written. The controller then pe...

A method and apparatus is disclosed for independently displaying one of a plurality of images on a display and for superimposing the plurality of images onto one another to produce a composite image. One or more bit planes are selected to constitute a group (defined to be a "surface"), and one or more additional bit planes are selected to constitute another group. The number of groups corresponds to the number of images to be independently displayed. The priority of one group over the other is s...

In a display system having a palette for chrominance and/or luminance information, a display buffer for information defining the pixels of a display field, including index values for indexing the palette select the chrominance and/or luminance of the pixels, a windowing mechanism is provided for associating a different range of index values with each of a plurality of windows and for responding to index values stored at individual pixel positions in the display buffer to determine the visible ex...

The present invention relates to a capability present within a graphics display terminal wherein a zoom operation may be accomplished, the width of each of the lines of the zoomed image being maintained at a one pixel width regardless of the degree or amount of magnification of the zoomed image. This is accomplished by utilizing the firmware stored in the processor to perform the magnification of the image therein, prior to the storage of the appropriate binary data in the video display memory, ...