JPH05145572A - Call takeover system of line duplicate equipment - Google Patents

Abstract

PURPOSE:To switch a line without interruption of a call and to restart communication without a fault on the line changeover request. CONSTITUTION:A line control LSI adds read/write of an internal register as a command and is provided with a read function of information required for call takeover and a write function recovering read information to an internal register of an opposite system LSI and also provided with a state freeze function to receive a frame from a line and to prevent revision of information on the way of read of a frame serial number or the like from an internal register. On the line changeover, the station in use is set to a busy state and the changeover is executed after the input is regulated, then the software control is implemented so as not to cause omission of a frame.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a call takeover system of a line duplexer using a line LSI having an intelligent function.

[0002]

2. Description of the Related Art L having a conventional intelligent function
In SI, the register information inside the LSI could not be read, so that the call takeover was realized by using the transparent mode which is controlled by the external software.

[0003]

In the conventional line control LSI having an intelligent function, it is premised that the line control device is designed in a single structure.

Therefore, even if a duplex configuration is realized by using this LSI, there is a drawback that the call cannot be taken over because the information such as the frame sequence number necessary for taking over the call cannot be read.

An object of the present invention is to provide a call takeover system of a line duplexer which can switch lines without disconnecting the call.

[0006]

In order to achieve the above object, in the call takeover method of the line duplexing apparatus according to the present invention, the internal register readable / writable line control LSI having an intelligent function is used for duplexing. Circuit controller and a selector for selecting the ACT system. When switching from the ACT system to the SBY system, the internal register of the LSI is read and the resource information is transferred to the partner system by software processing, and the transferred information is transferred. Write the resource information and the internal register of the LSI based on the
The change of the line state when switching from the T system to the SBY system is ensured by software processing, and call takeover is realized.

Further, in the line control LSI, read / write of an internal register is added as a command, a read function of information necessary for taking over a call and a write function of recovering the read information to an internal register of a partner LSI are provided. It has.

Further, in order to prevent the status from being changed by receiving the frame from the line while reading the frame serial number or the like from the internal register, it has a state freeze function.

[0009]

In the LSI of the present invention, the read / write of the internal register is added as a command, and the read function of the information necessary for taking over the call and the write function of recovering the read information to the internal register of the partner LSI are provided. .. The transfer of the read internal register information to the partner system is realized by software control.

Further, a state freeze function is provided in order to prevent the status from being changed by receiving a frame from the line while the frame serial number or the like is being read from the internal register.

[0011]

The present invention will be described below with reference to the drawings. FIG. 1 is a diagram in which call takeover is realized by the LSI of the present invention and software. The numbers used in the figure are the order of processing.

The present invention has a dual line control device I using a line control LSI capable of reading / writing an internal register having an intelligent function and a selector II for selecting an ACT system. When switching to, the internal register of the LSI is read, the resource information and the transfer to the partner system are performed by software processing, the resource information and the internal register of the LSI are written based on the transferred information, and the LSI internal state is guaranteed by software processing. A change in the line status when switching from the ACT system to the SBY system is guaranteed by software processing, and call takeover is realized.

In the line control LSI, read / write of an internal register is added as a command to read information necessary for call takeover and a write function of recovering the read information to the internal register of the partner LSI. Hold.

Further, a state freeze function is provided in order to prevent the status from being changed by receiving a frame from the line while the frame serial number or the like is being read from the internal register.

The processing contents are as follows. 1: Set own Busy state and restrict input. 2: The status inside the LSI is frozen. 3: Read status and various counter information from internal register. 4: Transfer the read information to the partner line control device. 5: The frame received during the state freeze is discarded. 6: Recover the received transfer information of 4 to the internal register. 7: Switch the line selector to the partner line control device. 8: Establish synchronization with the switched line control device. 9: Cancels own Busy and restarts communication.

[0016]

As described above, according to the present invention, the call can be taken over by the internal register read / write function of the LSI and the software, and the burden of the amount of software created can be reduced as compared with the conventional transparent mode. ..

[Brief description of drawings]

FIG. 1 is a circuit control device and a terminal (DT) when the present invention is realized.
It is a control sequence diagram (LAP-B procedure) between E).

[Explanation of symbols]

 I Line controller II Selector

Claims (3)

[Claims] 1. A dual line control device using an internal register readable / writable line control LSI having an intelligent function, and a selector for selecting an ACT system, and an LSI when switching from an ACT system to an SBY system. The internal register of is read and the resource information is transferred to the other system by software processing, the resource information and the internal register of the LSI are written based on the transferred information, and the internal state of the LSI is guaranteed by software processing. A call takeover method for a line duplexer that guarantees the change of line status when switching to a system by software processing and realizes call takeover. 2. In the line control LSI, a read / write of an internal register is added as a command, a read function of information necessary for taking over a call and a write function of recovering the read information to an internal register of a partner LSI are provided. The call takeover system of the circuit duplexer according to claim 1, wherein 3. A state freeze function is provided to prevent a status from being changed by receiving a frame from a line while reading a frame serial number or the like from an internal register. Call takeover method of the described redundant line equipment.