Line control adapter for a synchronous digital-formatted message-communications system

Claim 2

In a digital data-communications system having a plurality of terminals coupling a common communications path, at least two of the terminals being responsive to control characters expressed in different codes; wherein the system further includes: coupling means being interposed between a first terminal and the path, the coupling means comprising: means for continuously monitoring the data stream being generated by the first terminal, and for providing signal indication that a selected set of the monitored data stream corresponds to control characters expressed in a code different from that used by the first terminal; and means responsive to the signal indication for inserting a data element into the set sequence thereby converting the set sequence into a noncontrol character.

Claim 3

In a digital data-communications system according to claim 1, wherein the system further includes: another coupling means interposed between a second terminal anD the path, said second terminal being responsive to control characters expressed in the code used by the first terminal, the coupling means comprising: means for continuously monitoring the data stream generated by the first terminal and for providing signal indication that a selected set of the monitored data stream corresponds to the noncontrol character; and means responsive to the signal indication for removing the inserted data element from the monitored data set.

Claim 4

In a digital data-communications system according to claim 1, wherein the coupling means further include: means responsive to clocking signals from the first terminal for sequencing the data stream therethrough; and means responsive to the signal indication for interrupting the sequencing means for a time duration at least sufficient to insert the data element.

Claim 5

In a digital data-communications system according to claim 2, wherein the coupling means interposed between the second terminal and the path further include: means responsive to clocking signals accompany the data stream for sequencing the received data stream therethrough; and means responsive to the signal indication for interrupting the sequencing means for a time duration at least sufficient to remove the inserted data element.

Claim 6

In a digital data-communications system in which transmitted control characters define message framing, data character synchronization and the like, the system having: a common communications path; a plurality of terminals, at least one terminal being responsive to control characters expressed in a first code, and another terminal being responsive to control characters expressed in a second code; and means for coupling each terminal to the common communications path; wherein the coupling means include: means for monitoring the data stream being generated by a terminal expressing control characters in the first code; and means for altering that monitored data which appears as control characters expressed in the second code into noncontrol characters.

Claim 7

In a digital data-communications system in which transmitted control characters define message framing, data character synchronization and the like, the system having: a common communications path; a plurality of terminals, at least one terminal being responsive to control characters expressed in a first code, and another terminal being responsive to control characters expressed in a second code; and means for coupling each terminal to the common communications path; wherein the coupling means include: means for monitoring the data stream being generated by a terminal expressing control characters in the first code; and means for altering that monitored data which appears as control characters expressed in the second code into noncontrol characters.

Claim 8

In a digital data-communications system according to claim 5, wherein; the means for monitoring the data stream include; memory means containing control characters expressed in the second code; and means for providing signal indication of a comparison match between a set from the data stream and the contents of the memory means; the means for altering that monitored data include: means responsive to the signal indication for inserting a data element into the set sequence such that the set sequence mismatches the memory contents.

Claim 9

In a digital data-communications system having a plurality of terminals coupling a common communication path, at least two of the terminals being responsive to control characters expressed in different codes, wherein the system includes: coupling means interposed between each terminal and the communications path, the coupling means comprise: means for sequencing a data stream either generated by the associate terminal and applied to the path or received from the path; means for providing a first signal indication of a comparison match between a generated specified data sequence and a control character expressed in a code not used by the associate terminal; means responsive to the first signal indication for interrupting the sequencing means and inserting a data element such that the specified data sequence mismatches the compared control character; means for providing a second signal indication of a comparison match between a received specified data sequence and an arbitrary coded pattern; and means responsive to the second signal indication for removing at least one data character from the received sequence such as to create a mismatch between the sequence and the arbitrary pattern.

Claim 10

In a digital data-communications system having a plurality of terminals coupling a common communication path, at least two of the terminals being responsive to control characters expressed in different codes, wherein the system includes: coupling means interposed between each terminal and the communications path, the coupling means comprise: means for sequencing a data stream either generated by the associate terminal and applied to the path or received from the path; means for providing a first signal indication of a comparison match between a generated specified data sequence and a control character expressed in a code not used by the associate terminal; means responsive to the first signal indication for interrupting the sequencing means and inserting a data element such that the specified data sequence mismatches the compared control character; means for providing a second signal indication of a comparison match between a received specified data sequence and an arbitrary coded pattern; and means responsive to the second signal indication for removing at least one data character from the received sequence such as to create a mismatch between the sequence and the arbitrary pattern.