Martin D Roberts

US Patent:

47274956, Feb 23, 1988

Filed:

Oct 7, 1985

Appl. No.:

6/785152

Inventors:

Robert Cheetham - Longford, GB2
Martin Roberts - Phoenix AZ

Assignee:

The General Electric Company, p.l.c.

International Classification:

H04J 306

US Classification:

364514

Abstract:

The 16 kbit/s HDLC formatted signalling channel for each of 256 ISDN subscribers is separated from the data channel(s) at the exchange line circuit and TMD multiplexed into a 4 Mbit/s stream provided to a common signalling handler. In the handler, a receiving element processes each new bit of the 4 Mbit/s stream with 47 bits read out of a channel parameter store by a channel number provided by a channel allocation store. The 47 bits include the previous 7 received bits and a message byte address for that channel. When those 7 bits and the new bit form a new deformatted message byte, that byte is written into an incoming message store at a location determined by the current channel number and message byte address. Using a FIFO buffer, messages are read from the incoming message store by a processor in the order in which they are completed.