Hewlett-Packard Company

Rex L James

Robert E Watson

Jack M Walden

Wayne F Covington

Homer C Russell

Ivar W Larson

Fred Wenninger, Jr

Francis J Yockey

Emil E Olander, Jr

John C Keith

Douglas M Clifford

Bradley W Miller

Franklin T Hickenlooper

David C Uhlrich

Marl D Godfrey

Alan C Mortensen

Allen C Mortensen

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 programmable calculator is provided by employing modular read-write and read-only memory units capable of being expanded to provide the calculator with additional program and data storage functions oriented towards the environment of the user, a central processing unit, and an input-output control unit capable of bidirectionally transferring information between the memory or central processing units and a number of input and output units. The memory, central processor, and input-output control units are controlled by a microprocessor included in the central processing unit. The input and output units include a keyboard input unit with a plurality of sections capable of being defined by plug-in read-only memory modules and stored programs added by the user, a magnetic card reading and recording unit capable of bidirectionally transferring information between an external magnetic card and the calculator, a display unit capable of displaying every alphabetic and numeric character and many other symbols individually and in a line of one or more alphameric statements, and a printer unit capable of printing on thermally sensitive paper every alphabetic and numeric character and many other symbols individually and in alphameric statements or messages. The keyboard input unit includes a JUMP key for entering computed and uncomputed relative branch statements as part of a program stored in the calculator read-write memory. Upon execution of a relative branch statement, program execution is transferred a number of program lines forward or backward from the line containing the relative branch statement, as specified by that relative branch statement.

Programmable calculator including means for performing computed and

An adaptable programmable calculator is provided by employing modular read-write and read-only memory units capable of being expanded to provide the calculator with additional program and data storage functions oriented towards the environment of the user, a central processing unit, and an input-output control unit capable of bidirectionally transferring information between the memory or central processing units and a number of input and output units. The memory, central processor, and input-output control units are controlled by a microprocessor included in the central processing unit. The input and output units include a keyboard input unit with a plurality of sections capable of being defined by plug-in read-only memory modules and stored programs added by the user, a magnetic card reading and recording unit capable of bidirectionally transferring information between an external magnetic card and the calculator, a solid state output display unit capable of displaying every alphabetic and numeric character and many other symbols individually and in a line of one or more alphameric statements, and a line printer capable of printing on thermally sensitive paper every alphabetic and numeric character and many other symbols individually and in alphameric statements or messages. A printer spacing control command that may be executed either from the keyboard input unit or under control of a program stored in the read-write memory unit enables the user to introduce a blank space between printed lines on the paper, the blank space being equal to the number of lines specified in the printer spacing control command.

Programmable calculator including means for controllably introducing

An adaptable programmable calculator is provided by employing modular read-write and read-only memory units capable of being expanded to provide the calculator with additional program and data storage functions, a central processing unit, and an input-output control unit capable of bidirectionally transferring information between the memory or central processing units and a number of input and output units. The memory, central processing, and input-output control units are controlled by a microprocessor included in the central processing unit. The input and output units include a keyboard input unit, a magnetic card reading and recording unit, a solid state multi-character display unit capable of displaying every alphabetic and numeric character and many other symbols individually and in a line of one or more alphameric statements, and an alphameric printer unit. The calculator includes a TRACE key that permits the user to manually or programmably obtain an alphameric print-out of the number of each line of alphameric statements executed by the calculator and the value of each numeric assignment made therein. The calculator includes a NORMAL key for permitting the user to manually or programmably terminate a previously established TRACE mode of operation. An alphameric listing of each line of one or more alphameric statements, as that line is being executed by the calculator or stored as part of a program in the calculator read-write memory, may be obtained when the calculator is operating in the TRACE mode.

Programmable calculator including program trace means

An adaptable programmable calculator is provided by employing modular read-write and read-only memory units capable of being expanded to provide the calculator with additional program and data storage functions oriented towards the environment of the user, a central processing unit, and an input-output control unit capable of bidirectionally transferring information between the memory or central processing units and a number of input and output units. The memory, central processor, and input-output control units are controlled by a microprocessor included in the central processing unit. The input and output units include a keyboard input unit having a plurality of alphabetic, numeric, and funtion keys for entering alphameric information, including algebraic statements, into the calculator, a magnetic card reading and recording unit capable of bidirectionally transferring information between an external magnetic card and the calculator, a solid state display unit capable of displaying every alphabetic and numeric character and many other symbols individually and in a line of one or more alphameric statements, and a printer unit capable of printing on thermally sensitive paper every alphabetic and numeric character and many other symbols individually and in alphameric statements or messages. At least one of the function keys of the keyboard input unit is a dual function key. One of the dual functions is selected by actuating the key once, and the other one of the dual functions is selected by actuating the key twice.

Programmable calculator including multifunction keys

An adaptable programmable calculator is provided by employing modular read-write and read-only memory units capable of being expanded to provide the calculator with additional program and data storage functions, a central processing unit, and an input-output control unit for bidirectionally transferring information between the memory or central processing units and a number of input and output units. The memory, central processor, and input-output control units are controlled by a microprocessor included in the central processing unit. The input and output units include a keyboard input unit, a magnetic card reading and recording unit, a solid state multi-character display unit capable of displaying every alphabetic and numerical character and many other symbols individually and in a line of one or more alphameric statements, and a thermal printer unit. The keyboard input unit includes a DISPLAY key that permits the user to manually or programmably display the results of an arithmetic expression, an alphameric message, or the contents of any designated data register, either singly or as a string, and without thereby altering the contents of the data register. Mnemonic representations of each key of the keyboard input unit appear in the display and are automatically scrolled to the left of the display as additional keys are actuated. Displayed strings of alphameric characters may be manually scrolled left or right across the display by selective actuation of a pair of display control keys. The display may be cleared independently of any memory registers.

Programmable calculator including scrolling alphanumeric display means

An adaptable programmable calculator is provided by employing modular read-write and read-only memory units capable of being expanded to provide the calculator with additional program and data storage functions oriented towards the environment of the user, a central processing unit, and an input-output control unit capable of bidirectionally transferring information between the memory or central processing units and a number of input and output units. The memory, central processor, and input-output control units are controlled by a microprocessor included in the central processing unit. The input and output units include a keyboard input unit with a plurality of sections capable of being defined by plug-in read-only memory modules and stored programs added by the user, a magnetic card reading and recording unit capable of bidirectionally transferring information between an external magnetic card and the calculator, a solid state display unit capable of displaying every alphabetic and numeric character and many other symbols individually and in a line of one or more alphameric statements, and a printer unit capable of printing on thermally sensitive paper every alphabetic and numeric character and many other symbols individually and in alphameric statements or messages. The keyboard input unit includes a MINUS arithmetic operator key that initiates either the unary minus function or the subtraction function, as the context of an entered algebraic statement employing the MINUS arithmetic operator requires.

Programmable calculator including a key for performing either a

An adaptable programmable calculator is provided by employing a modular read-write and read-only memory unit capable of being expanded to provide the calculator with additional program and data storage functions oriented towards the environment of the user, a central processing unit capable of performing both serial binary and parallel binary-coded-decimal arithmetic, and an input-output control unit capable of bidirectionally transferring information between the memory or central processing units and a number of input and output units. The memory, central processor, and input-output control units are controlled by a microprocessor included in the central processing unit. The input and output units include a solid state output display unit capable of displaying every alphabetic and numeric character and many other symbols individually and in a line of one or more alphameric statements and an output printer unit capable of selectively printing every alphabetic and numeric character and many other symbols individually and in alphameric statements or messages. Questions may be asked of the user and user instructions and other alphameric messages may be given by the output display unit. Answers to those questions and output data may be subsequently printed on the output printer unit without printing the questions, user instructions, and messages displayed by the output display unit.

Programmable calculator including alphanumeric display means

An adaptable programmable calculator is provided by employing modular read-write and read-only memory units capable of being expanded to provide the calculator with additional program and data storage functions oriented towards the environment of the user, a central processing unit, and an input-output control unit for bidirectionally transferring information between the memory or central processing units and a number of input and output units. The memory, central processor, and input-output control units are controlled by a microprocessor included in the central processing unit. The input and output units include a keyboard input unit, a magnetic card reading and recording unit, a solid state multi-character output display unit capable of displaying every alphabetic and numeric character and many other symbols individually and in a line of one or more alphameric statements, and a thermal printer unit. The keyboard input unit includes a display control key for entering a DISPLAY statement into the calculator and an execute control key for initiating execution of a line of alphameric statements entered into the calculator. The DISPLAY statement may be manually or programmably employed to cause the calculator to display the results of arithmetic expressions, alphameric messages, or the contents of any memory register without thereby altering the contents thereof. By means of fixed point and floating point control keys, the user may manually or programmably designate either fixed point or floating point notation for all subsequently displayed data. The notation currently in effect may be altered by the user during program execution by simply actuating either the fixed point or floating point control key.

Programmable calculator including data format display control means

An adaptable programmable calculator is provided by employing modular read-write and read-only memory units capable of being expanded to provide the calculator with additional program and data storage functions oriented towards the environment of the user, a central processing unit, and an input-output control unit capable of bidirectionally transferring information between the memory or central processing units and a number of input and output units. The memory, central processor, and input-output control units are controlled by a microprocessor included in the central processing unit. The input and output units include a keyboard input unit with a plurality of sections capable of being defined by plug-in read-only memory modules and stored programs added by the user, a magnetic card reading and recording unit capable of bidirectionally transferring information between an external magnetic card and the calculator, an output display unit capable of displaying every alphabetic and numeric character and many other symbols individually and in a line of one or more alphameric statements, and a printer unit capable of printing on thermally sensitive paper every alphabetic and numeric character and many other symbols individually and in alphameric statements or messages. The calculator includes a multiplicity of programmable boolean flag variables that may be designated from the keyboard input means and employed as part of an alphameric statement. Selected ones of the boolean flag variables may be manually set from the keyboard at any time during execution of a program stored in the read-write memory. A dedicated one of the boolean flag variables is automatically set by the calculator when a mathematically incorrect program statement or an arithmetic underflow or overflow is encountered during program execution.

Programmable calculator including boolean flag variable means

An adaptable programmable calculator is provided by employing a modular read-write and read-only memory unit capable of being expanded to provide the calculator with additional program and data storage functions oriented towards the environment of the user, a central processing unit capable of performing both serial binary and parallel binary-coded-decimal arithmetic, and an input-output control unit capable of bidirectionally transferring information between the memory or central processing units and a number of input and output units, such as a keyboard and an output display unit. The memory, central processor, and input-output control units are controlled by a microprocessor included in the central processing unit. Data storage registers within the calculator memory may be addressed directly by the computed integral value of an arithmetic expression that may in turn incorporate the contents of one or more similarly addressed data storage registers, thus facilitating efficient fetching and storing of information, as well as matrix operations and manipulation of files. A plurality of dedicated data storage registers having fixed labels and locations within the calculator memory may, by single key actuations on the part of the user, be called into a displayed algebraic expression, the contents of which are then manipulated in accordance with the algebraic expression.

Programmable calculator employing computed memory addresses

An adaptable programmable calculator is provided by employing modular read-write and read-only memory units capable of being expanded to provide the calculator with additional program and data storage functions oriented towards the environment of the user, a central processing unit, an input-output control unit for bidirectionally transferring information between the memory or central processing units and a number of input and output units. The memory, central processor, and input-output control units are controlled by a microprocessor included in the central processing unit. The input and output units include a keyboard input unit, a magnetic card reading and recording unit, a solid state display unit capable of displaying every alphabetic and numeric character and many other symbols individually and in a line of one or more alphameric statements, and an output printer unit capable of printing on thermal sensitive paper every alphabetic and numeric character and many other symbols individually and in alphameric statements or messages. Syntactical errors in a line of one or more alphameric statements being entered into the calculator from the keyboard input unit are automatically detected and immediately indicated to the user as they occur. Nonsyntactical errors in a line of one or more alphameric statements previously entered into the calculator and stored as a program in the read-write memory are automatically detected during execution of the line in which the error is present. Such errors, together with identification of the erroneous line, are visually indicated to the user. Both syntactical and nonsyntactical errors are communicated to the user by way of visually displayed alphameric messages that indicate the nature of the error encountered. A number of editing keys are provided to permit the user to view the line of alphameric statements in which an error has been detected to facilitate efficient correction of that error.

Programmable calculator including alphanumeric error display means

An adaptable programmable calculator is provided by employing a modular read-write and read-only memory unit capable of being expanded to provide the calculator with additional program and data storage functions oriented towards the environment of the user, a central processing unit, and an input-output control unit capable of bidirectionally transferring information between the memory or central processing units and a number of input and output units. The memory, central processor, and input-output control units are controlled by a microprocessor included in the central processing unit. The input and output units include a keyboard for entering alphameric information, including algebraic statements, into the calculator, a magnetic card reading and recording unit, a solid state output display unit capable of displaying every alphabetic and numeric character and many other symbols individually and in a line of one or more alphameric statements, and a printer unit capable of printing on thermally sensitive paper every alphabetic and numeric character and many other symbols individually and in alphameric statements or messages. The calculator includes an implied multiplication feature whereby algebraic statements entered into the calculator are entered without the multiplication operator but are, nevertheless, processed as if the multiplication operator were present at the appropriate points in those algebraic statements.

Programmable calculator including means for performing implied multiply

An adaptable programmable calculator is provided by employing modulr read-write and read-only memory units capable of being expanded to provide the calculator with additional program and data storage functions oriented towards the environment of the user, a central processing unit, an input-output control unit for bidirectionally transferring information between the memory or central processing units and a number of input and output units. The memory, central processor, and input-output control units are controlled by a microprocessor included in the central processing unit. The input and output units include a keyboard input unit, a magnetic card reading and recording unit, a solid state display unit capable of displaying every alphabetic and numeric character and many other symbols individually and in a line of one or more alphameric statements, and a printer unit capable of printing on thermally sensitive paper every alphabetic and numeric character and many other symbols individually and in alphameric statements or messages. A printed listing of the line number and content of each line of one or more alphameric statements stored as part of a program in the read-write memory unit may be obtained by means of a LIST control key of the keyboard input unit. The user may also obtain, directly or as part of any program listing, a printed indication of the number of nondedicated storage registers within the calculator read-write memory that are currently available to the user for information storage.

Growing community of inventors

Loveland, CO, United States of America

Rex L James