JPH0685946A - Method for control of call in isdn switching system - Google Patents

Abstract

PURPOSE: To simply manage a call by using a static memory. CONSTITUTION: After initializing the hardware, a mount/dismount state of a board is checked and a call management area is assigned. In the case that mount/dismount state data are dissident with data stored in a PC, data are sent to the PC to attain a protocol standby state. On the occurrence of an SDLC interrupt, a received message is analyzed and protocol processing is conducted and on the occurrence of serial interrupt, an extension number management mode, a current traffic status information transmission mode or a debugging mode is set (steps 18-25) depending on a value set to a transmission information area of the message.

Description

Detailed Description of the Invention

[0001]

The present invention relates to ISDN (Integrated S
service digital network) and, more particularly, to a call control method of NT2 or NT12 capable of switching a large number of ISDN terminals and the like.

[0002]

2. Description of the Related Art In a conventional digital private branch exchange or keyphone system, when the power is cut off, it is impossible to properly back up the current system status. After that, the system configuration and extension number were assigned.

Further, although a conventional private exchange normally supports an analog terminal and a digital terminal, when an attempt is made to connect with an analog terminal, a signal is detected from the DTMF receiving circuit and a digital signal is privately transmitted through A / D conversion. Although it is transmitted to the main control unit of the exchange, when the digital terminal tries to connect, the steps of DTMF signal detection and A / D conversion are omitted.

At this time, the progress order of the message related to the call and the contents in the message use the signal executed by the private branch exchange and the ISDN terminal in a system-dependent manner without depending on the standardization. And 1 on any time axis
Since no more than one call can be in progress for one ISDN terminal at a time, the main control that manages the call can easily manage the call using static memory.

[0005]

However, in the ISDN environment, since a large number of calls exist for one ISDN terminal at the same time, it is difficult to control the calls using the static memory. That is, since one ISDN terminal has at least two B channels and calls for each B channel are independent, at least two calls must be generated to connect each B channel. Never,
Further, since a number of calls are alternately present on one B channel on the time axis, it is difficult to predict the number of calls that one ISDN terminal can request.

The present invention has been made in view of the above conventional problems, and is the main unit of ISDN keyphones or ISDN.
It is an object of the present invention to provide a call control method for an ISDN switching system, which is applicable not only to a private exchange but also to a call control of an ISDN local exchange.

[0007]

Therefore, in order to achieve the above-mentioned object, the present invention is connected to a subscriber's ISDN terminal via a plurality of subscriber connection boards, and is connected to a station line via a station line connection board. A main control unit for controlling switching of the ISDN terminal of the subscriber by connecting to the storage unit for call management from the ISDN terminal of the subscriber, and connecting to the main control unit to exchange information with the main control unit. A computer for transmitting and receiving a call is provided, while the initialization state of each subscriber connection board or office line connection board is inspected for disconnection, and the call control corresponding to each board installed in the storage means of the main control unit. A first step of allocating an area and determining whether or not there is a connection with the computer after the allocation, and receiving the dismounting state information already stored in the computer and comparing it with the dismounting state information obtained in the inspection And both The second step of determining whether the wearing state information matches or not, and after the second step, when the two pieces of the detachment state information are different from each other, the detachment state information obtained in the inspection is transmitted to the computer, and the protocol is transmitted. A third step of maintaining a standby state, and when an SDLC (Synchronous Data Link Control) interrupt from the subscriber connection board occurs in the third step, the SDLC interrupt process is performed to receive a message from the subscriber. Analyze
When a call is mapped by the storage means of the main control unit when a call is present, protocol processing is performed, and when a serial interrupt from the computer occurs, the serial interrupt processing is performed, and after receiving a command from the computer is analyzed. And a fourth step of analyzing the transmission information by determining the transmission information area in the reception command.

In addition, a fifth step is provided in which the message format of the reception command exchanged with the computer at the time of the fourth step serial interrupt processing is the same as the SDLC format. Further, when a call management area is allocated to the storage means in the first step, a call dedicated area is provided, and when a call start request is received from an arbitrary subscriber or an office line connection board, a call is generated and a call confirmer is identified. It is provided with a sixth step of assigning and assigning to the call dedicated area.

[0009]

According to the above construction, the detached state of each subscriber connection board is inspected in the first stage, and the call management area corresponding to each installed board is assigned to the storage means of the main control section. The disassembly state information is recognized by the computer, and the main control unit is managed by a reception command from the computer.

Therefore, even if a large number of calls exist on the time axis, the calls are assigned to the call management area and the main control unit is managed by the computer, so that the computer can manage the calls. Further, by including the fifth step and making the format of the reception command the same as the SDLC format, the reception command analysis process is integrated with the reception message analysis process, and the analysis processing method can be unified. Become.

Further, when the call management area is allocated to the storage means by providing the sixth step, by providing a call dedicated area and allocating the call confirmer, the time for searching for the call confirmer can be greatly reduced.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following is a detailed description with reference to the accompanying drawings of an embodiment of the present invention for achieving the above object. First, FIG. 1 is a block diagram of an NT12 system. A main control unit (1) having a call control and switching system maintenance security function includes a subscriber connection board (2) and a primary group connection board (Primary Rate Interface, 30B). + D)
(3), U connection board (4), and PC (5) as a computer.

One subscriber connection board (2) has eight'S '
It is possible to support the interface. Again 1
The next group connection board (3) and the U connection board (4) are station line connection boards, and among them, the first group connection board (3) is a primary line access board that supports a 2-line CEPT interface. , U connection board (4) is a basic access board supporting an 8 "U" interface.

Here, each of the subscriber connection boards (2) is
The numbers bd0 to bd5 are assigned. The U interface board (4) is assigned the number bd10h, the primary group access board (3) is assigned the number bd20h, and the main control unit (1) is assigned the number bdFFh. There is. The ST-bus is connected to the switch IC in the main control unit (1) and used as a B channel path.

The main controller (1) and the PC (5) are RS-2
Connected through 32, PC (5) is PC when needed
The drive device of (5) is used to store extension connection information and extension numbers for connected subscribers, and a screen is displayed when the operator inquires the PC (5) about the current traffic status. . FIG. 2 is a block diagram showing an embodiment of the main control unit (1),
The switching units (7) and D are provided in the U and the related circuit (6).
Channel connection (8), eg 4 Mbit SRA
A system memory (9) serving as a storage unit composed of M, a system clock generation circuit (10), a deep switch (11), a serial interface unit (12), a real time clock unit (13), etc. are connected.

FIG. 3 shows an embodiment in which the memory is allocated based on the information of the number of boards obtained when the 4-megabit SRAM of the system memory (9) is initialized, which will be described later. Hereinafter, the operation and effect of the present invention will be described with reference to FIG.
A detailed description will be given based on the flowcharts of FIGS. 7 and 7, and FIGS.

Steps (denoted by "S" in the figure,
In the same manner 1), when the power of the system is turned on, the main control unit (1) initializes the respective units such as the switching unit (7) in the board and the serial port. In step 2, the SDLC format message of the received message as shown in FIG. 4 is transmitted on the 2 Mbps RS-485 loop through the SCC ₁ terminal, and each subscriber connection board (2) or the primary group which is the office line connection board is transmitted. The detached state (not mounted state) of the connection board (3) and the U connection board (4) is inspected.

In order to enable the main control unit (1) to detect which of the subscriber connection boards (2) mounted in the NT12 system is connected, the address on the receiving side of the received message is set. Is the board number (0-7, 10
h, 20h), your own address FFh as the sender address, the subscriber status as "0", and E0h as the transmission information.
Each board or the like that has transmitted to the LC and has received this exchanges the address of the receiver with the address of the sender, sets the subscriber status to "1" and returns it to the main control unit (1).

In step 3, the main control unit (1) combines the returned information and checks the number and status of the currently mounted boards. That is, if the subscriber status is "1", it is determined that the board corresponding to the sender address is mounted. Memory of the system memory (9) is allocated based on this inspection result. The system corresponding to the present embodiment can accommodate a maximum of six subscriber connection boards and two office line connection boards in total, but for example, the subscriber connection board (2) is bd0, bd2, bd3, Assuming that only the primary line connection board (3) is installed in the bd5 slot and the station line connection board is installed, the system requires about 100 bytes of memory to process one call. Therefore, the memory allocation for call management is as follows.

That is, as shown in FIG. 3, a 128 Kbyte area is allocated for call management on the subscriber side, and a 128 Kbyte area is allocated for call connection on the station line side. These are call management areas. FIG. 5 shows addresses related to call management on the subscriber side. The 32 Kbyte area for each subscriber board is allocated to the 128 Kbyte area for call management on the subscriber side. Dividing the memory in this way can greatly improve speed.

If the system memory (9) is not divided into such sub-blocks, the following situation will occur. First, when a call start request is received from the extension subscriber connection mode through the SDLC line, the main control unit (1) generates a call confirmer by generating a random number,
By designating an arbitrary memory, the sender confirms the caller and the SDLC board number obtained from the SDLC stores information necessary for the progress of the subscriber address general protocol.

When an arbitrary primitive that is not a call start request arrives through the SDLC line, this SDLC
Since the frame contains the call confirmer and the sender board number, the subscriber address, etc., it is necessary to search the memory for a memory area containing the same call confirmer based on this information. Therefore, as shown in FIG. 5, when the memory is allocated on the basis of the board, it is possible to greatly reduce the time required to search the mapped call confirmer.

As described above, after checking whether or not the board is allocated and securing the call-dedicated area, in step 4, RS
After checking whether the PC (5) is connected through the -232C port, if not connected, the process proceeds to step 9. If a PC (5) is connected,
Proceeding from step 4 to step 5, receiving the data already stored from the PC (5), comparing it with the inspected detachment state data in step 6, and proceeding to step 9 if the data are not different from each other, If they are different, step 8
Then, after transmitting the detected data of the detached state to the PC (5), the process proceeds to step 9.

In step 9, the protocol standby state is entered. In this protocol wait state, one of the SDLC interrupt and serial interrupt that has already been set is activated to process the input. The priority of SDLC interrupt is set higher than that of serial interrupt. In step 10, it is detected whether SDLC interrupt has occurred.

If an SDLC interrupt occurs, the process proceeds to step 11, where the SDLC interrupt process is performed, and then the received message is analyzed in step 12. The SDLC format of such a received message is as shown in FIG. 4 as described above, and the call confirmer is included in the information area of the received message. In step 13, it is judged whether or not the call confirmer actually exists in the information area.

If the call confirmer does not exist in the information area, the process proceeds from step 13 to step 14 to determine whether the received message is a call setup request. If it is a call setting request, after a call is generated in step 15, the call is registered according to the board number in the already secured call management memory area, and the process proceeds to step 17. If there is a call confirmer in the information area, proceed to step 16, extract the board number from the received message, and map it to the call-only area,
Search for the same call confirmer and proceed to step 17.

In step 17, protocol processing is performed.
When a serial interrupt is generated from the PC (5), the process proceeds from step 10 to step 18, the serial interrupt process is performed, and then the process proceeds to step 19, the message of the received reception command is analyzed, and when the SDLC interrupt occurs. In order to be integrated with the process of analyzing the received message, the message format exchanged with the PC (5) is defined as the SDLC format. Then, at the time of initialization, the PC (5) is regarded as one mounting board, it is confirmed that it is bdE8h, and then the transmission information area of FIG. 4 is analyzed.

If the value of the transmission information area is "1", the procedure proceeds from step 20 to step 21 to enter the extension management mode, and if it is "2", the procedure proceeds to steps 20 → 22 → 23 and the current call management area. Traffic status transmission, and if it is "3", proceed to steps 22 → 24 → 25 to enter the debugging mode. In the extension number management mode of step 21, the operation instruction of FIG. 4 is further analyzed. However, if the operation instruction area is set to “1”, the extension number assignment instruction causes a message as shown in FIG. 8 (A). It is configured to extract messages in the information area and logically assign extension numbers.

If the operation command area is set to "2" as shown in FIG. 8B, the information area becomes 8 bytes, and the current extension number to be changed to the first 4 bytes is the next 4 bytes. The current extension number to be changed to a byte contains the ASCII value of the extension number after the change to the next 4 bytes. Further, when the operation command area is set to "3" as shown in FIG. 8C, the information area does not exist and the default (default) setting is required, and the main control unit (1) is currently inspected. The numbers are sequentially assigned from 2000 in the order of the board and the order of the S subscriber interface in the board.

If the extension number assignment / change / default setting is successful, the main control unit (1) sends a completion message as shown in FIG. As in E), the failure reason is P in ASCII value
Send to C (5). If the transmission information area is "2", the current traffic status information transmission is performed in step 23. At this time, the frame format input from the PC (5) is as shown in FIG. 9 (F).

The main control unit (1) transmits the number and status of calls currently in progress as shown in FIG.
When the number of bytes exceeds the maximum, it is segmented into 1024-byte units and transmitted to the PC (5). Each time the PC (5) receives 1024 bytes without error, it sends a message indicating successful reception as shown in FIG. PC (5) in main controller (1)
If the (H) message is not received even though 3 seconds have passed after sending the data to the device, it will try to retransmit up to 3 times, but if it fails continuously, it will be sent to the PC (5). It is determined that the connection has been disconnected, and the process returns to step 10.

At this time, the PC (5) requests the main control unit (1) to report the current traffic status with the message of FIG. 9 (F) and then receives the message of FIG. 10 (G).
Although the message (G) is output in order to (5), the contents output to the screen include the number of currently existing calls, the call confirmer of each call, the sender of each call, and the receiver of each call. , The current state of each call, etc.

According to this structure, since the call management area is allocated to the system memory (9) and the call exclusive area is also allocated, two or more calls can be simultaneously made to one terminal on an arbitrary time axis. You can proceed and greatly reduce the time to find a mapped call verifier. In addition, since the message format of the reception command exchanged between the PC (5) and the main control unit (1) is defined to be the same as the SDLC format, the reception message analysis process is integrated, and the analysis processing method is used. Can be unified.

[0034]

As described above, according to the present invention,
Switching device or ISDN private exchange, ISDN,
The call processing technology of NT12 and NT2 and the technology relating to the user interface section can be effectively applied to the main unit of the digital keyphone and the ISDN private exchange, and also to the call control of the ISDN local exchange.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an NT12 system of the present invention.

FIG. 2 is a configuration diagram of a main control unit of the present invention.

FIG. 3 is a diagram showing allocation of system memory according to the present invention.

FIG. 4 is a diagram showing an SDLC frame format of the present invention.

FIG. 5 is a diagram showing an example of allocation of a call management area after board status inspection according to the present invention.

FIG. 6 is an operation flowchart of the main control unit of the present invention.

FIG. 7 is an operation flowchart of the same as above.

FIG. 8 is an exemplary diagram showing a structure of a message in an information area according to an extension number assignment command of the present invention.

FIG. 9 is an exemplary view of the same.

FIG. 10 is an exemplary diagram of the same as above.

[Explanation of symbols]

 1 Main Control Section 2 Subscriber Connection Board 3 Primary Group Connection Board 4 U Connection Board 5 PC 6 CPU and Related Circuits 7 Switching Section 8 D Channel Connection Section 9 System Memory 10 System Clock Generation Circuit 11 Deep Switch 12 Serial Interface Section 13 Real-time clock section

Claims (3)

[Claims] 1. A main control unit for connecting to an ISDN terminal of a subscriber through a plurality of subscriber connection boards, and connecting to an office line through a station line connection board to control switching of an ISDN terminal of the subscriber. A storage means for call management from the ISDN terminal of the subscriber is provided, and a computer that is connected to the main control unit and transmits / receives information to / from the main control unit is provided. The detachment state of the station line connection board is inspected, the call control area corresponding to each equipped board is assigned to the storage means of the main control unit, and after the assignment, the presence or absence of the connection with the computer is determined. The first step and the second step of receiving the dismounting state information already stored in the computer, comparing it with the dismounting state information obtained in the inspection, and determining whether the two pieces of dismounting state information match or do not match.
And, after the second step, when the two pieces of dismounting state information are different from each other, transmitting the dismounting state information obtained by the inspection to a computer to maintain a protocol standby state, and SDLC from the subscriber connection board in three steps
When a (Synchronous Data Link Control) interrupt occurs, the SDLC interrupt process is performed, the received message from the subscriber is analyzed, and the protocol process is performed after the call mapped by the storage means of the main control unit when the call exists. Then, when a serial interrupt from the computer occurs, the serial interrupt processing is performed to analyze the reception command from the computer, and then the transmission information area in the reception command is determined to analyze the transmission information. A call control method for an ISDN switching system, comprising: 2. The fifth step according to claim 1, further comprising a fifth step in which a message format of a reception command transmitted / received to / from the computer is made the same as an SDLC format in the fourth step serial interrupt processing. I
A call control method for an SDN switching system. 3. A call-dedicated area is provided when a call management area is assigned to the storage means in the first step, and a call is generated when a call start request is received from an arbitrary subscriber or an office line connection board. The call control method for an ISDN switching system according to claim 1, further comprising a sixth step of assigning a call confirmer and allocating the call confirmer to the call dedicated area.