Scientific calculator
AssigneeHewlett-Packard Company
InventorsPeter D. Dickinson, Thomas E. Osborne, France Rode, Allen J. Baum
Life of this patent
Estimating the term…
Abstract
A battery powered hand-held calculator for performing arithmetic, triganometric and logarithmic functions and displaying the results thereof is provided with a clock mode which performs the function of a clock and displays real time or the function of a stopwatch and stores and displays the times at which recorded events have taken place.
Claims33
An electronic calculator having a calculator mode and a time-calculating mode for use as a realtime time-keeping device, comprising:
- an input unit, including a plurality of manually operable keys, for initiating the modes of operation of the calculator;
- a memory unit for storing microinstructions;
- a plurality of storage registers for storing a plurality of numbers representing progressively larger units of time;
- a processing unit, coupled to the input unit, memory unit and storage registers, responsive in the time-calculating mode to a preselected total number of microinstructions executed per smallest unit of time being calculated by the processing unit for repetitively incrementing the number representing the smallest unit of time, that number being zeroed when it exceeds a selected value, and, following each such zeroing of that number, incrementing the numbers representing each remaining progressively larger unit of time when the number representing the largest preceding unit of time relative thereto is zeroed, said lastmentioned numbers being zeroed when they exceed selected values, unless the number being incremented represents the largest unit of time, that number being reset to unity when it exceeds a selected value;
- and
- an output display unit coupled to the processing unit for displaying the incremental values of the numbers representing units of time.
An electronic calculator having a calculator mode and a stopwatch mode, comprising:
- an input unit including a manually operable means for initiating the mode of operation of the calculator, and a plurality of keys having legends associated therewith;
- a plurality of split-time storage registers coupled to the input unit for storing numbers representing split times;
- a processing unit, coupled to the input unit and storage registers, responsive to actuation of one of the keys when the calculator is in the stopwatch mode for storing a number representing a split time in a split-time storage register, the legend of the key actuated being effective for associating the split-time storage register in which that number is stored with the key actuated;
- and
- a display unit coupled to the processing unit for displaying the numbers stored in the split-time storage registers.
A combination calculator and real-time clock having a calculator mode and a time-calculating mode comprising a case, an electro-optical digital display on the case, a calculator keyboard on the case, electronic calculator means in the case coupled to the keyboard, and means for coupling the calculator means to the display;
- said calculator means including processing means for performing calculator functions in the calculator mode, and including memory means for storing micro-instructions and a plurality of numbers representing progressively larger units of time, said processing means alternatively performing real-time time-calculating functions in the time calculating mode in response to a preselected total number of micro-instructions executed per smallest unit of time being calculated by the processing means for repetitively incrementing the number representing the smallest unit of time, that number being zeroed when it exceeds a selected value, and, following each such zeroing of that number, incrementing the number representing each remaining progressively larger unit of time when the number representing the largest preceding unit of time relative thereto is zeroed, said last mentioned numbers being zeroed when they exceed selected values, unless the number being incremented represents the largest unit of time, that number being reset to unity when it exceeds a selected value.
A combination calculator and real-time clock as in claim 24 wherein:
- the calculator keyboard further includes a plurality of non-numeric keys;
- and
- the calculator means is responsive to actuation of one of the numeric keys when sequentially preceded by actuation of one of the non-numeric keys for causing the number stored in a split-time storage register associated with that numeric key to be displayed by the display.
A combination calculator and stopwatch having a calculator mode and a stopwatch mode comprising a case, an electro-optical digital display on the case, a calculator keyboard on the case, electronic calculator means in the case coupled to the keyboard, and means for coupling the calculator means to the display;
- said calculator means including processing means for performing calculator functions in the calculator mode, and including memory means for storing micro-instructions and a plurality of numbers representing progressively larger units of time, said processing means alternatively performing elapsed-time time-calculating functions in the stopwatch mode in response to a preselected total number of micro-instructions executed per smallest unit of time being calculated by the processing means for repetitively incrementing the number representing the smallest unit of time, that number being zeroed when it exceeds a selected value, and, following each such zeroing of that number, incrementing the number representing each remaining progressively larger unit of time when the number representing the largest preceding unit of time relative thereto is zeroed, said last mentioned numbers being zeroed when they exceed selected values, unless the number being incremented represents the largest unit of time, that number being reset to unity when it exceeds a selected value.
A combination calculator, real-time clock and stopwatch having a calculator mode, a time-calculating mode and a stopwatch mode comprising a case, an electro-optical display on the case, a calculator keyboard on the case, electronic calculator means in the case coupled to the keyboard, and means for coupong the calculator means to the display;
- said calculator means including processing means for performing calculator functions in the calculator mode, and including memory means for storing micro-instructions and a plurality of numbers representing progressively larger units of time, said processing means alternatively performing real-time time-calculating functions in the time calculating mode and elapsed-time time-calculating functions in the stopwatch mode in response to a preselected total number of micro-instructions executed per smallest unit of time being calculated by the processing means for repetitively incrementing the number representing the smallest unit of time, that number being zeroed when it exceeds a selected value, and, following each such zeroing of that number, incrementing the number representing each remaining progressively larger unit of time when the number representing the largest preceding unit of time relative thereto is zeroed, said last mentioned numbers being zeroed when they exceed selected values, unless the number being incremented represents the largest unit of time, that number being reset to unity when it exceeds a selected value.
Dependencies are inferred from the claim text.