Hewlett-packard Company

John C Keith

Douglas M Clifford

Robert E Watson

Rex L James

Freddie W Wenninger

David Steven Maitland

Donald E Morris

Louis T Schulte

Marl D Godfrey

Bradley W Miller

Franklin T Hickenlooper

Jindrich Kohoutek

David C Uhlrich

Brad E Clements

Alan C Mortensen

Steven Paul Tucker

David J Hodge

Lief J Sorensen

Allen C Mortensen

A method and apparatus for use in read/write operations by a processor that reads and writes information in first and second address formats. The method and apparatus include a memory and a memory mapper for remapping according to a predetermined scheme those memory fragments not containing information stored in the first address format. Memory fragments are thus accessible to the processor for reading and writing information in the second address format. Such remapping operation results in the memory fragments appearing logically contiguous. In the preferred embodiment, the first address format is an x-y address format and the second address format is a linearly addressable format. An alternative embodiment discloses the use of a second memory for reading and writing information in the second address format. In that embodiment, the memory mapper remaps the memory fragments to appear logically contiguous with said second memory. The invention finds particular utility in conjunction with a graphics processor system. In such a system, the memory mapper is a programmable array logic device and the memory is VRAM memory. In certain situations it is preferred to remap that portion of the memory where information is to be stored in the first address format so that the first information signal is stored in locations which are physically contiguous.

Method and apparatus for the mapping of physically non-contiguous memory

A handheld stylus for a digitizer includes a tip that is angled downward to meet the digitizing surface at almost, but not quite, a right angle. The body of the stylus is of a generally triangular cross section. Mounted upon the stylus are pushbutton switches actuatable by a force along a line essentially at right angles to the digitizing surface when the stylus is in use. An anti-rolling winged member keeps the stylus from rolling when it is laid over on its top after use.

Ergonomic digitizer stylus

A digitizer platen or tablet incorporates a recess within its surface. The recess has plural multiples of four interior corners for interlocking with predetermined sizes of rectangular paper wherein no two lengths are equal and no two widths are equal. Menus are plotted or otherwise prepared upon the predetermined sizes. The menu preparation is such that when a sheet of any of the predetermined sizes is registered within its corresponding interior corners of the recess there obtains a constant (X, Y) offset between a selected point of reference upon the tablet, such as the origin, and a selected point of reference upon the menu. Such automatic constant offset with registration frees the operator of the digitizer from manually instructing the applications software as to the exact location of the menu.

Graphics tablet menu locator accommodating differing sizes of paper

An electronic calculator includes modular read-write and read-only memory units, a central processing unit, an output display unit, an output printer unit, a keyboard input unit, and input/output interface circuitry for facilitating the connection of one or more peripheral input/output units, such as an X-Y plotter, for example, to the calculator. When the calculator is coupled to an X-Y plotter, the user may employ commands entered from the keyboard input unit to move the plotter pen to an arbitrary position on the plotter platen whose X and Y coordinates are unknown to him and to subsequently cause the calculator to determine and display the X and Y coordinates of that arbitrary pen position.

Programmable calculator including means for digitizing the position of

An adaptable programmable calculator employs modular read-write and read-only memories separately expandable to provide additional program and data storage functions within the calculator oriented toward the environment of the user, an LSI NMOS central processing unit, and LSI NMOS peripheral interface adaptor capable of bidirectionally transferring information between the read-write memory and central processing unit and a number of input/output units. The input/output units include a keyboard input unit with a plurality of alphanumeric keys, a magnetic tape cassette reading and recording unit capable of bidirectionally transferring programs and data between a magnetic tape and the calculator, a seven-segment gas discharge display, and a 16-column alphanumeric thermal printer. The calculator includes switch means for selecting an auto start mode of calculator operation whereby, upon the application of operating power to the calculator, a program stored on an external magnetic record member is automatically loaded into the calculator read-write memory and execution of that program is commenced.

Programmable calculator including means for automatically processing

An adaptable calculator is provided by employing five MOS/LSI circuits interconnected by a multiple line bus system. They include (1) a read-only memory circuit group; (2) a control and timing circuit; (3) an arithmetic and register circuit; (4) a data storage circuit; and (5) an input/output (I/O) circuit. Input and output units include a keyboard input unit and an 18-column output printer unit for printing intermediate results of calculations, entered data, arithmetic operators, and diagnostic notes. The keyboard input unit includes a PERCENT key that may be employed in combination with any of four arithmetic operator keys. The calculator may be operated manually by the user from the keyboard input unit or automatically by a program written in user-level language and stored in a plug-in read-only memory unit (ROM), a plug-in programmable read-only memory unit (PROM) or a read/write memory unit associated with a plug-in magnetic card reading and recording unit.

Adaptable programmed calculator including a percent keyboard operator

An adaptable calculator is provided by employing five MOS/LSI circuits interconnected by a multiple line bus system. They include (1) a read-only memory circuit group; (2) a control and timing circuit; (3) an arithmetic and register circuit; (4) a data storage circuit; and (5) an input/output (I/O) circuit. Input and output units include a keyboard input unit and an 18-column output printer unit. An optional LED display unit may be plugged into the calculator mainframe. The keyboard input unit includes an AUTO DECIMAL POINT key for selecting an automatic decimal point mode of calculator operation in which the calculator automatically places the decimal point at a specified location in all entered data. Thus, the operator need not manually enter the decimal point in entered data. The calculator may be operated manually by the user from the keyboard input unit or automatically by a program stored in the calculator memory.

Adaptable programmed calculator including automatic decimal point

An adaptable programmable calculator employs modular read-write and read-only memories separately expandable to provide additional program and data storage functions within the calculator oriented toward the environment of the user, an LSI NMOS central processing unit, and an LSI NMOS peripheral interface adaptor capable of bidirectionally transferring information between the read-write memory and central processing unit and a number of input/output units. The modular read-write memory includes a movable boundary between a program storage section thereof and a data storage section thereof to permit the user to adjust the size of those sections of the read-write memory in accordance with his present problem solving requirements. The input/output units include a keyboard input unit with a plurality of alphanumeric keys, a magnetic tape cassette reading and recording unit capable of bidirectionally transferring programs and data between a magnetic tape and the calculator, a seven-segment gas discharge display for displaying data entered into the calculator, the results of computations, and selected alphanumeric messages, and a 16-column alphanumeric thermal printer for printing results of computations, program listings, messages generated by the user and the calculator itself, and error conditions encountered during use of the calculator. All of these input/output units are included within the calculator itself. Many other external input/output units may be employed with the calculator. The calculator may be operated manually by the user from the keyboard input unit or automatically through a program stored within the read-write memory to perform calculations and to provide an output indication of the results thereof. The calculator employs reverse polish notation (RPN) language including an operational stack of registers for efficiently evaluating algebraic expressions. The language is arranged on a modified key per function basis, incorporating some of the features of higher level languages such as loops. The language also includes sophisticated editing features that enhance the usefulness of the calculator.

Programmable calculator employing a read-write memory having a movable

An adaptable calculator is provided by employing five MOS/LSI circuits interconnected by a multiple line bus system. They include (1) a read-only memory circuit group in which subroutines for performing arithmetic and other functions of a basic keyboard input unit are stored; (2) a control and timing circuit for scanning the keyboard, for retaining status information relating to the condition of the calculator or of a particular subroutine, and for generating a next address in read-only memory; (3) an arithmetic and register circuit containing an adder, a group of working registers, a group of data storage registers forming a stack, and a constant storage register; (4) a data storage circuit which provides ten data storage registers, nine of which are employed by the calculator system and one of which is available to the user for storing data; and (5) an input/output (I/O) circuit for enabling the calculator to communicate with various I/O peripheral units such as a typewriter and an X-Y plotter, for performing binary arithmetic by means of a binary arithmetic logic unit contained therein, and for performing various system housekeeping operations. Input and output units include a keyboard input unit having a receptacle for accommodating a 15-key function block to enlarge the capabilities of the calculator and an 18-column output printer unit for printing intermediate results of calculations, entered data, arithmetic operators, and diagnostic notes. An optional 15-digit seven-segment light emitting diode (LED) output display unit may be inserted into the calculator mainframe. All of these input and output units are included within the calculator itself. An X-Y plotter, a typewriter, a marked sense card reader, an extended data storage memory, a magnetic card reading and recording unit, a ASCII bus for enabling the calculator to communicate with data gathering instruments, and many other peripheral input and output units may also be employed with the calculator. The calculator may be operated manually by the user from the keyboard input unit or automatically by a program written in user-level language and stored in a plug-in read-only memory unit (ROM), a plug-in programmable read-only memory unit (PROM) or a read/write memory unit associated with a plug-in magnetic card reading and recording unit.

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Loveland, CO, United States of America

John C Keith