Programmable calculator including multifunction keys
US4178633A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 1, 1977 |
| Grant date | Dec 11, 1979 |
| Priority date | — |
| Expiry date | Jun 1, 1997 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F15/0233
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
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 …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.