JPS58107748A - Modulation and demodulation device - Google Patents

Abstract

PURPOSE:To execute automatically self-diagnosis, by starting a folding circuit and a self-diagnosis circuit through the detection of the application of power supply for a modulation and demodulation device. CONSTITUTION:The modulation and demodulation device 1 is connected to a terminal device 2 and a communication line 3, and when a power supply of the device 1 is turned on, a starter 11 detects it and transmits a start signal to make an analog switch 6 into a folding state and to change over a switching circuit 7 from the terminal device 2 to the self-synthesis circuit 8. When the start signal starts the circuit 8 via a delay circuit 12, a test signal is transmitted from a signal transmission/reception section 8a and folded back to a reception section 5 via the switching circuit 7, a transmission section 4 the analog switch 6. The signal is returned to the section 8a again via the switching circuit 7, the transmission/reception signals are compared, and either one of lamps 9 and 10 is illuminated in accordance with coincidence/dissidence, and the propriety of test results is displayed.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention relates to a modem and, more particularly, to a modem and a modem that can automatically perform self-diagnosis.

(b) Prior Art and Problems In online systems in which host computers and terminals are installed far apart from each other, the host computers and terminals are connected to a communication line via a modem and cannot transmit data to each other. is being carried out.

When a communication failure occurs in the above system, the modem is usually provided with a self-diagnosis circuit in order to identify whether the cause of the failure is in the communication line or the modem. Therefore, when a communication failure occurs, the location of the failure can be easily found by operating the self-diagnosis circuits of the modem devices at both ends of the line.

However, conventionally, the above-mentioned self-diagnosis circuit has been configured to be operated manually, but since communication failures occur only rarely, the user has almost no opportunity to operate the above-mentioned self-diagnosis circuit. I am not familiar with the operation method. Therefore, when a communication failure actually occurs, engineers from the manufacturer must be dispatched to both ends of the line, and it takes a long time to identify the failure location, which can seriously impede system operation. vinegar.

fcl OBJECTS OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and provide a modulation/demodulation device that can automatically perform self-diagnosis.

fd) Structure of the Invention A feature of the present invention is that the modem is equipped with a starter that sends out a start signal when the power is turned on, and a delay circuit. In addition to sending a start signal to the switch circuit and the switching circuit to activate them, the self-diagnosis circuit is also activated via a delay circuit, so that self-diagnosis can be performed automatically.

Embodiment of the Invention The drawing is a main system configuration diagram showing an embodiment of the invention.

In the figure, 1 is a modem, 2 is a terminal, 3 is a communication line, 4 is a transmitter, 5 is a receiver, 6 is an analog switch,
7 is a switching circuit, 8 is a self-diagnosis circuit, which consists of a test signal transmitting/receiving section 8a, a judgment section 8b, and a display section 8C;
O is a lamp that indicates whether the modem w1 is good or bad. The above is no different from conventional modem devices. In this embodiment, the starter 11 and the delay circuit 1
2 has been added.

With this embodiment, when the power is turned on, the starter 11 detects this, sends out a start signal, operates the analog switch 6 and the switching circuit 7, and first switches the modem l to its own state. 0 to make it diagnosable
The signal is then sent to the self-diagnosis circuit 8 via the delay circuit 12 to activate it. When the self-diagnostic circuit 8 is activated, a test signal is sent from the signal transmitting/receiving section 8a. This signal is transmitted to the switching circuit 7. Transmission unit 4. The signal is returned to the receiving section 5 via the analog switch 6, and from the receiving section 5 returns to the transmitting/receiving section 8a via the switching circuit 7. The judgment section 8b compares this with the test signal sent from the above-mentioned transmitting/receiving section 8a, and if the two match, it outputs a "good" signal, and when they do not match, it outputs a "bad" signal.
Then either lamp 9 or lO is turned on.

As described above, the self-diagnosis of the modulation/demodulation device 1 is completed, and its quality is automatically confirmed. Thereafter, a test completion signal is sent from the self-diagnosis circuit 8, and the starter 11 is reset, thereby returning the modem 1 to the normal communication state.

As described above, according to this embodiment, it is possible to always check whether there is any abnormality in the modem wl when starting up the system. Furthermore, when a communication failure occurs, self-diagnosis of the modulation/demodulation device 1 can be performed simply by turning the power on and off. Therefore, it is possible to immediately know whether the cause of the failure is in the modem 2t or the communication line 3.

(f) DETAILED DESCRIPTION OF THE INVENTION As described above, the present invention provides a modulation/demodulation device that can automatically perform self-diagnosis.

[Brief explanation of the drawing]

The drawing is a main system configuration diagram showing an embodiment of the present invention. In the figure, 1 is a modem, 3 is a communication line, 6 is an analog switch, 7 is a switching circuit, 8 is self-diagnostic, and 8a
.
0 is a display lamp, 11 is a starter, and 12 is a delay circuit.

Claims (1)

[Claims] It is equipped with a transmitter, a receiver, a self-diagnostic circuit, a switching circuit, and an analog switch, and by activating the switching circuit and analog switch and then activating the self-diagnostic circuit, In a modulation/demodulation device that can self-diagnose the quality of the modulation/demodulation device by returning the test signal sent from the reception section to the reception section and comparing the signal sent from the reception section with the test signal in a self-diagnosis circuit, A starter that sends a start signal when the power is turned on to the modem and a delay circuit is attached, and the starter sends a start signal to the analog switch and the switching circuit when the power is turned on to switch them. 1. A modulation/demodulation device characterized in that the self-diagnosis circuit is activated via a delay circuit at the same time as the self-diagnosis circuit is activated so that the self-diagnosis can be automatically performed.