United States Patent 4,177,520
Calculator apparatus having a single-step key for displaying and executing program steps and displaying the result
| Issued: | Dec. 4, 1979
|
|---|
| Inventor: | Randall B. Neff, Menlo Park, Calif.
|
|---|
| Assignee: | Hewlett-Packard Company, Palo Alto, Calif.
|
|---|
| Appl. No.: | 604,696
|
|---|
| Filed: | Aug. 14, 1975
|
|---|
Abstract:
A programmable electronic calculator is provided having an LED display
device and a single-step key for causing display and execution of
individual steps of a program stored in the calculator, and for causing
display of the results of said execution by means of a single actuation
of the single-step key. As the key is depressed, the next program step
that is to be executed is displayed, together with the number of that
step in the program. When the key is released, the program step is
executed and the result is displayed.
12 Claims, 2 Drawing Figures
PDF file of US Patent 4,177,520 (546K)
Back to the HP Calculator Patents page
Back to my home page
Last updated May 31, 2003
Copyright 2003 Eric Smith
eric@brouhaha.com
check now