US 4,792,969 AGranted

Line condition data collecting system for a telephone exchange

AssigneeFujitsu Limited

InventorsYuji Shibata, Atsushi Fujihira

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Abstract

A line condition data collecting system for a telephone exchange includes an image memory in a central processing unit which stores line condition data to reduce the amount of time the central controller in the central processing unit waits for the line condition data. A signal receiving memory in the telephone exchange stores the line condition data and is sequentially accessed by an image memory controller autonomously from the central controller in the central processing unit. When the central controller requires line condition data, the image memory is checked and if the line condition data stored therein is valid, it is supplied to the central controller. If the line condition data in the image memory is invalid, a conventional access request is made to the signal receiving memory, but this occurs less frequently than in a conventional system.

Claims10

Dependent claims

A line condition data collection system for a telephone exchange, comprising:

signal receiving memory means for holding line condition data of a plurality of lines;
and
processing means for periodically collecting the line condition data and for controlling the telephone exchange, comprising:
central control means for executing commands controlling execution of said processing means, the commands including a readout command;
and
image memory means for sequentially reading the line condition data from said signal receiving memory means independently of the commands executed by said central control means, for storing validity flags, corresponding to the line condition data, indicating whether the line condition data stored in said image memory means is valid and, in response to execution of the readout command by said central control means, for supplying specific line condition data stored in said image memory means to said central control means if a corresponding validity flag indicates that the specific line condition data is valid.

3 more elements

Dependencies are inferred from the claim text.