发明名称 |
Data communications systems employing redundant series transmission loops |
摘要 |
A loop communication system includes a loop controller originating and terminating parallel output multiple bit message frames over a pair of trunks to remote stations, each of which includes a multiplexing connection means to the incoming trunk segments, with means to selectively and operably connect one of the incoming trunk segments to a frame processor. A pair of transmitters are also provided at the interface means and actuated to synchronously and correspondingly retransmit the process signal over the two outgoing trunk lines or segments. A logic circuit directly transmits the signal from one receiver and blocks the other until the first fails. The message is processed and retransmitted by a pair of transmitters over the two outgoing trunk segments. Suitable indicators coupled into the logic circuit signal the failure. A contact status circuit initiates transmission of the failure location via message frames to the controller. A control switch by-passes the station and is operable manually or in response to a power failure.
|
申请公布号 |
US4159470(A) |
申请公布日期 |
1979.06.26 |
申请号 |
US19770797368 |
申请日期 |
1977.05.16 |
申请人 |
JOHNSON CONTROLS INC |
发明人 |
FROEHLING, PAUL;GALASZEWSKI, ROBERT D;STROJNY, LAWRENCE J |
分类号 |
H04L1/22;H04B1/74;H04B17/00;H04L12/437;(IPC1-7):H04Q9/00;G08C25/00 |
主分类号 |
H04L1/22 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|