JPH05122211A - Frame synchronization system - Google Patents

Abstract

PURPOSE:To simplify a fault detection circuit of a receiver side communication equipment by reducing the hardware quantity of a sender side communication equipment and simplifying the configuration circuit in the communication equipment adopting the synchronization system using a frame signal. CONSTITUTION:An interface section 4 of a sender side communication equipment 1 is provided with a frame phase storage section 5 storing and generating a subordinate frame signal having the same phase and period as those of a frame signal inputted when the communication equipment 1 is normal. When the communication equipment 1 at the sender side is normal, the subordinate frame signal in matching with the frame signal is used and sent to the receiver side communication equipment. When the frame signal is interrupted due to a fault of the communication equipment 1, the subordinate frame signal stored in the frame phase storage section 5 is outputted with the same phase and period as those before the interruption. The outputted subordinate frame signal is employed and the transmission to the receiver side communication equipment is implemented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a frame synchronization system that uses a signal for frame synchronization between communication devices for data communication to perform synchronization.

[0002]

2. Description of the Related Art Conventionally, in a communication apparatus using this type of frame synchronization method, an independent frame signal having a phase different from that of a frame signal input from the inside of the transmitting side apparatus is generated in an interface section with a counterpart apparatus. Then, the data and the like input from the inside of the device are synchronized and transmitted to the partner device.

[0003]

In the above-described conventional frame synchronization method, the phase of the frame signal, data, etc. input from the inside of the device on the transmission side is different from the phase of the independent frame signal generated in the interface unit, so that the interface unit However, there is a drawback in that the phases must be matched, the amount of hardware in the interface section increases, and the configuration circuit becomes complicated.

[0004]

A frame synchronization system of the present invention is a frame synchronization system that uses a signal for frame synchronization between communication devices that perform data communication to achieve synchronization. The interface unit is provided with means for storing and generating a subordinate frame signal having the same phase and cycle as the phase and cycle of the frame signal input during normal operation of the communication apparatus, so that the inside of the communication apparatus on the transmission side is normal. In this case, the subordinate frame signal matched with the frame signal is used, and when the frame signal is interrupted due to an internal failure of the communication device on the transmitting side, the subordinate frame signal stored in the means is interrupted. The configuration is such that the same phase and cycle as before are output, and the output dependent frame signal is used to transmit to the communication device on the receiving side.

[0005]

The present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of an embodiment of the present invention.
The interface unit 4 includes a frame phase storage unit 5 having a frame phase storage function, a clock transfer unit 6 having a clock transfer function, and an interface unit clock 7 for generating a clock signal, and communicates with the inside 3 of the apparatus. The device 1 is configured. Communication device 1
Is connected to the communication partner 2 and transmits a dependent frame having the same phase and cycle as the phase and cycle of the frame signal input during normal operation of the communication device 1, data and an interface clock, and communicates by the frame synchronization method. It is carried out.

Next, the operation of the present invention will be described. Data, frames and clocks are input to the interface unit 4 from the inside 3 of the device. The data, frame and clock input to the interface unit 4 are transferred to the clock of the interface unit clock 7 by the clock transfer unit 6. The frame changed to the interface clock is input to the frame phase storage unit 5.

As shown in FIG. 2, the frame phase storage unit 5 is composed of a counter 8 which operates on the clock of the interface unit. The input frame is input to the set terminal S of the counter 8 and the data terminal D is supplied for each frame. The interface unit 4 receives a signal from the clock 7 uniquely possessed by the interface unit 4 via the terminal CK according to the set value set in the above, and outputs the dependent frame from the terminal Q in the same phase as the input frame.

The counter 8 outputs dependent frames at the same cycle as the frame cycle input during normal operation. Even if the internal frame 3 is interrupted and the input frame is interrupted and data is not set, the counter 8 is stored during normal operation. Dependent frames are output with the same period and the same phase as in the normal state. Further, when the inside of the apparatus 3 returns to normal, the input frame also returns to normal, and a dependent frame matching the phase of the newly input frame is output.

[0010]

As described above, according to the present invention, when communication is performed using the synchronization method using a frame signal, the frame signal is not interrupted by an internal failure of the device and is transmitted by the communication partner device. Since it is possible to know the other party's abnormality by judging only the data, it is possible to reduce the amount of hardware in the communication device on the transmission side and simplify the configuration circuit, and to simplify the abnormality detection circuit in the communication destination device. effective.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration example of a frame phase storage unit in FIG.

[Explanation of symbols]

 1 communication device 2 communication partner 3 device internal 4 interface unit 5 frame phase storage unit 6 clock transfer unit 7 interface unit clock 8 counter

Claims (1)

[Claims] 1. In a frame synchronization method for performing synchronization by using a signal for frame synchronization between communication devices that perform data communication, the interface unit of the communication device on the transmission side is input when the communication device is operating normally. Means for storing and generating a subordinate frame signal having the same phase and period as the phase and period of the frame signal to be generated, and when the inside of the communication device on the transmitting side is normal, the subordinate signal corresponding to the frame signal is provided. When a frame signal is used and the frame signal is interrupted due to an internal failure of the communication device on the transmitting side, the dependent frame signal stored in the means is output in the same phase and cycle as before the interruption, and is output. A frame synchronization method characterized in that a dependent frame signal is used and transmitted to a communication device on the receiving side.