Converter device for a computer terminal
US4601010A · kind A · utility
Inventor
Key dates
| Filing date | Dec 19, 1983 |
| Grant date | Jul 15, 1986 |
| Priority date | — |
| Expiry date | Dec 19, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG09G1/16
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A converter device which enables a computer terminal having text display capability only to be used for displaying either graphics or text and graphics simultaneously in addition to text is disclosed. The device connects in series between the video output port of the terminal electronics section of the computer terminal and the video input port of the CRT electronics section of the computer terminal and in parallel with the RS232 port of the computer terminal to an external source of serial data signals and includes a microprocessor controlled relay which allows either video signals generated by the control electronics section of the computer terminal or internally generated video signals to be transmitted to the CRT electronics section, a fail-safe switch which allows the computer terminal to function normally in the event of a malfunction in the device, a data processing system having a microprocessor, a character generator read-only memory and video refresh memory section containing random access memory elements for storing graphic data and random access memory elements for storing ASCII code signals representative of characters and selection circuitry for selecting which memory…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.