JPS6084035A - Common transmitter - Google Patents

Abstract

PURPOSE:To detect easily a fault of a line by duplicating a multiplexer and a demultiplexer in a common transmitter transmitting plural trains of signals as time division multiplex signals and providing a test controller and a test signal detector. CONSTITUTION:When a signal is transmitted to input controllers 24, 25 from a test controller 23, the input controller, e.g., 24 transmits an input signal 1 to a multiplexer 2 and the input controller 25 transmits an H or L test signal to a multiplexer 20 at all times. Since the test controller 23 transmits a signal to output controllers 26, 27 at the same time, the output controller 26 transmits the output of the demultiplexer 4 as an output signal 5 and the output controller 27 avoids the output of the demultiplexer 22 from being given as the output signal 5. Moreover, a signal detector 29 confirms that the H level test signal is detected from the demultiplexer 22. The test controller 23 switches the said operation for the system of the multiplexer 2 and 20 alternately and transmits data while confirming no failure in both the transmission systems.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a shared transmission device that transmits a plurality of signals as time-division multiplexed signals, and in particular to failure detection of a line thereof.

FIG. 1 is a block wiring diagram showing an example of a conventional shared transmission device.
+1:t multiplexer, (31 is a transmission line for transmitting the output of this multiplexer, (4: this transmission line), and a demultiplexer for separating the signals; 15) is the signal output of the multiplexer 1j.

In the shared transmission device configured as described above, multiple columns of signal inputs (11) are sent out from the transmission path (3) as time-division multiplexed signals by the multiplexer (21). Time division multiplexing (K number is separated by lI into a plurality of signals by a demultiplexer (41) and output as a plurality of columns of signal outputs (5).

However, because the conventional shared transmission equipment is configured as described above, it has drawbacks such as failures in the multiplexer (2) and demultiplexer (41) cannot be detected, and failures in the transmission line (31) cannot be detected. .

This invention was made to eliminate the above-mentioned drawbacks of the conventional equipment. The purpose of this invention is to provide a highly reliable shared transmission device that can be easily monitored.

FIG. 2 is a lock connection diagram showing one embodiment of the present invention, and (1) to (5) indicate the same reference numerals and 1- or corresponding parts as in FIG. 1. In the figure, (20) is a multiplexer that constitutes a separate line from multiplexer (2), (2 is a transmission line that transmits the output of this multiplexer,
(22) is a demultiplexer that separates the signal from this transmission line, (23) a test controller that controls switching of the U line, (24) (25) is a multiplexer +z+, 12I with the signal from this test controller, respectively. (26 (27) are respectively output controllers that control the output signals from the demultiplexers (41, (22)); (28 (29) are each a demultiplexer (4); ,
(22) is a signal detector for detecting a fault signal from.

In the shared transmission device configured as described above, when a signal is sent from the test controller (23) to the input controller (24 (25)), for example, the input controller (24) receives the input signal tl.
l 'e multiplexer (2) and input controller (2
5) always sends a "H" (or "L") test signal to the multiplexer (20).At the same time, the test controller (
Since the output controller (23) also sends a signal to the output controller (26 (27), the output controller (26) sends the output of the demultiplexer (41) to the output signal (51), and the output controller (27) sends the output of the demultiplexer (41) to the output signal (51). The output of (22) is not output to the output signal +51.

Also, the signal detector (29) confirms that the "H" test signal from the demultiplexer (22) is detected,
Make sure that the transmission system from multiplexer (20) to transmission line (2υ) to demultiplexer (22) is normal.
) and the multiplexer (201), data is transmitted while confirming that there is no failure in both transmission systems.

As explained above, by duplicating multiplexers and demultiplexers, and providing one test controller and a test signal detector, this invention can always detect whether the line is normal, thereby creating a highly reliable shared transmission device. There is an effect that can be obtained.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an example of a conventional shared transmission device, and FIG. 2 is a block diagram showing an embodiment of the present invention. In the figure (2) t unit multiplexer,
(41 is a demultiplexer, (20) is a U multiplexer, (22) is a demultiplexer, (23) is a test controller, and (28) and (29) are signal detectors. The same reference numerals in each figure indicate the same - or The relevant portion shall be shown. Agent Masuo Oiwa

Claims (1)

[Claims] A shared transmission device comprising a multiplexer that sends out multiple columns of signals as a time division multiplexed signal, and a demultiplexer that demodulates the received time division multiplexed signal into multiple columns of signals, two pairs of multiplexers and demultiplexers, and the above-mentioned A test controller that alternately transmits a time division multiplexed signal and a test signal to two multiplexers, and a test signal detector that receives the test signal and detects that the line that transmitted the test signal is normal. A shared transmission device characterized by being equipped with a device.