US 4,287,567 AGranted

High speed central office scanner

AssigneeUniversal Industrial Control Devices Ltd.

InventorJames R. Lumsden

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Abstract

The invention relates to a high speed central office scanner for use with a plurality of transponding units connected by telephone lines. The scanner is comprised of N, I/O units, each comprised of a multiplexer for connecting the I/O units to M telephone lines; a microprocessor and multiplex logic which sequentially selects one of the M telephone lines; a busy detect circuit for checking the selected telephone line and providing a signal when the line is busy; a TX/RX unit connected to the selected line for transmitting an instruction code to a transponder connected thereto when the signal is absent and for receiving data from the transponder in response to the instruction code; and a storage unit. The scanner further includes a master microprocessing unit, which includes a main microprocessor for sequentially selecting one of the N, I/O units and for generating an interrogating code for transmission to each selected I/O unit. Each master microprocessor unit includes a master storage unit for storing received data from the selected I/O unit and a main TX/RX unit for transmitting the received data stored in the main storage unit, upon receipt of a further interrogation code, wherein each of the N, I/O units scan the M telephone lines independently and asynchronously with respect to each other of the N, I/O units and the master microprocessing unit.

A high speed central office scanner for communicating with a plurality of transponding units connected by telephone lines;

said scanner is comprised of:
A. N, I/O means, where N is a positive integer, each I/O means comprising:
(a) multiplex means for connecting said I/O means to M telephone lines, each telephone line being connected to at least one transponder, where M is a positive integer;
(b) a microprocessor;
(c) multiplex logic means, controlled by said microprocessor for sequentially selecting one of said M telephone lines;
(d) a bush detect means for checking said selected line and producing a signal when said selected line is busy;
(e) transmitting-receiving means connected to said selected line, controlled by said microprocessor for transmitting an instruction code to a transponder connected thereto when said signal is absent, and receiving data from said transponder in response to said instruction code;
(f) storage means;
and
(g) I/O interface logic means,
wherein said microprocessor analyzes the received data and enters the received data in said storage means if the received data satisfies a predetermined criterion;
B. master microprocessor means comprising:
(a) interface logic means connected with said I/O interface logic means of each of said N, I/O means;
(b) a main microprocessor for sequentially selecting one of said N, I/O means and for generating an interrogation code for transmission to each selected I/O means to enquire if said selected I/O means has received data stored therein;
(c) main storage means for storing received data from said selected I/O means;
and
(d) main transmitting-receiving means for transmitting said received data stored in said main storage means upon receipt of a further interrogation code;
wherein each said N, I/O means scan said M telephone lines independently and asynchronously with respect to each other of said N, I/O means and said master microprocessor means.

15 more elements

Abstract

Claims9