초록 ▼

In a data communication system including a plurality of remote units under the control of a master controller, whereby each of the remote units operates to transmit and receive data from the master controller, an interface circuit for connecting each remote unit to the controller includes a switchin

In a data communication system including a plurality of remote units under the control of a master controller, whereby each of the remote units operates to transmit and receive data from the master controller, an interface circuit for connecting each remote unit to the controller includes a switching transistor operable via a timing network for turning on to apply a high level signal continuously on the remote data output terminal of the associated interface circuit, for effectively isolating the malfunctioning remote transceiver, while permitting normal system operation without interference from the malfunctioning unit.

대표청구항 ▼

A data communication system comprising: a plurality of remote devices each including a loop return line for passing data to and transmitting data from the remote device; a plurality of interface circuits each associated with an individual one of said plurality of remote devices, respectively, each h

A data communication system comprising: a plurality of remote devices each including a loop return line for passing data to and transmitting data from the remote device; a plurality of interface circuits each associated with an individual one of said plurality of remote devices, respectively, each having a first terminal for connection to an end of said loop return line, the latter having another end connected to said remote device, a second terminal for receiving data to transfer to said loop return line, and a third terminal for transmitting data received from the associated said remote device via said loop return line; master controller means having a plurality of transmit data lines connected individually to said second terminals of said plurality of interface circuits, respectively, and an input data line for receiving data from said plurality of remote devices; AND gate means having a plurality of input lines connected individually to said third terminals of said plurality of interface circuits, respectively, and an output terminal connected to an end of said input data line of said master controller means; and each one of said interface circuits include isolation circuit means for applying a digital “1”on the associated third terminal in response to said associated remote device faulting, by its loop return line becoming either open-circuited or shorted to a source of reference potential, thereby effectively isolating the associated remote device from said AND gate means, while permitting said AND gate means to be primed for passing data from the normally operating ones of said remote devices to said master controller means.