Programmable calculator
US4075679A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 8, 1975 |
| Grant date | Feb 21, 1978 |
| Priority date | — |
| Expiry date | Dec 8, 1995 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F15/02
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
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, and an LSI NMOS central processing unit, capable of handling sixteen-bit parallel binary operations, binary-coded-decimal arithmetic, sixteen-bit parallel input/output operations, two-level interrupt from up to sixteen input/output devices, and a direct memory access channel. The input/output units include a keyboard input unit having a full complement of alphanumeric keys, a magnetic tape cassette reading and recording unit capable of bidirectionally transferring programs and data between the calculator and a magnetic tape, a 32-character solid state output display unit capable of displaying every alphabetic and numeric character and many other symbols individually or in combination, and a sixteen-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 w…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.