The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 09, 1987
Filed:
Jan. 31, 1985
Richard E Bugg, Coulsdon, GB;
U.S. Philips Corporation, New York, NY (US);
Abstract
A character memory of a data display arrangement is divided into a plurality of separate memory sections which are available to provide characters for display only for respective sub-areas of a display screen. The invention is especially suited to providing high resolution character-based displays using so-called dynamically redefinable characters sets. A memory map MM containing the memory sections is addressed by a counter COU. A latch L2 initially sets the counter COU to the address of the first memory section. During each line scanning period a .div.2 divider DV is responsive to character column pulses CP to step the counter COU to address a new memory section address evey second character position. At the end of each line scanning period line pulses LP reset the counter COU to the first memory section address. In a modification, the connections of the address bus between the counter and the memory map are altered so that the addresses as actually applied to the memory sections are only changed every second (or fourth) character position so that less memory is needed.