Dixson T Jen

US Patent:

40854426, Apr 18, 1978

Filed:

Mar 31, 1975

Appl. No.:

5/563527

Inventors:

Sigitas Julius Liaukus - Huntington CT
Dixson Teh-Chao Jen - Monroe CT

Assignee:

Bunker Ramo Corporation - Oak Brook IL

International Classification:

G06F 314

US Classification:

364900

Abstract:

A programmable read-only memory (PROM) provides a fixed stored microroutine to logic circuitry which controls the fetching of data from a memory to a variable number of video display units. The microroutine includes a small number of micro subroutines that are utilized to fetch the addresses in a separate main memory, where character data is to be found. Similarly, subroutines are provided for obtaining entry marker (cursor) addresses from the main memory. Additional subroutines are provided for indirectly addressing the main memory for the character data which undergoes encoding by a character generator that is capable of providing video information to eight channels.