The following operators can be used to better focus your queries.
( ) , AND, OR, NOT, W/#
? single char wildcard, not at start
* multi char wildcard, not at start
(Cat? OR feline) AND NOT dog?
Cat? W/5 behavior
(Cat? OR feline) AND traits
Cat AND charact*
This guide provides a more detailed description of the syntax that is supported along with examples.
This search box also supports the look-up of an IP.com Digital Signature (also referred to as Fingerprint); enter the 72-, 48-, or 32-character code to retrieve details of the associated file or submission.
Concept Search - What can I type?
For a concept search, you can enter phrases, sentences, or full paragraphs in English. For example, copy and paste the abstract of a patent application or paragraphs from an article.
Concept search eliminates the need for complex Boolean syntax to inform retrieval. Our Semantic Gist engine uses advanced cognitive semantic analysis to extract the meaning of data. This reduces the chances of missing valuable information, that may result from traditional keyword searching.
A technique incorporated in an improved interrupt refresh subroutine saves processor time by reducing subroutine overhead.
English (United States)
This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately
80% of the total text.
Page 1 of 2
Reduced Program Overhead for Software Generated Dynamic Memory
A technique incorporated in an improved interrupt refresh subroutine saves
processor time by reducing subroutine overhead.
Dynamic memory requires periodic refresh to maintain its information
content. For data to be retained, each memory cell must be addressed within a
time limit. Heretofore, a typical low cost refresh method is to periodically interrupt
the system processor and have an interrupt service subroutine perform 128 row
address sequential read. This software refresh operation is accomplished by
using the low order seven address bits, and is repeated every two milliseconds.
More specifically, this refresh operation is accomplished by 64 sequential
"dummy" POP instructions. Such periodic row address sequential read,
however, takes up considerable processor time and adversely impacts its
The table below illustrates an improved interrupt refresh subroutine (see
original). which reduces program overhead for such software-generated dynamic
memory refresh. The improved refresh subroutine makes use of the OP Codes
and the instructions needed in the set-up and execution of the subroutine to
generate refresh cycles. This technique also takes advantage of the fact that
refresh of the 128 row address memory locations need not be sequential. By
placing the refresh subroutine on a 128-byte boundary region, the execution of
each subroutine step generates one or more read cycles, which...