JPS5953575B2 - Communication control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a communication control system, and in particular, in a station system having a processing device and a communication control device, the communication control device autonomously transmits an incoming call rejection signal or a controlled not ready signal. The present invention relates to a communication control system configured to reduce interruptions to the processing device.

FIG. 1 is a connection topology diagram when a station system having a processing device and a communication control device communicates with another station system or a terminal device via a circuit switching network. In the figure, 1 indicates a switching network, 2 is a line termination device, 3 is a communication control device, 4 is a central processing unit, and 5 is a terminal device. In such a line switching system, the station system or terminal device must perform control operations with the switching network 1 based on an interface called an X20 interface or an X21 interface. When receiving an incoming call from the other party, the X20 interface must send an incoming call rejection signal to the network if the incoming signal received from the network cannot be received. Furthermore, if the system becomes unable to receive a call using the X2l interface, it must continuously transmit a controlled not ready (CNR) signal to the network, regardless of whether or not there is an incoming call. Figure 2a shows an example of a conventional communication control method when transmitting an incoming call rejection signal based on the This is an example of a conventional communication control method when transmitting.

5. The communication control device has a channel control word for each line, and is configured so that the contents of the channel control word are updated sequentially based on the progress of processing. The content of the channel control word is periodically read out and the firmware executes the process to be executed at the relevant timing.

For this reason, the figure expresses the above-mentioned firmware processing in the form of a flowchart for the sake of simplicity. The operation of the conventional method when a call is received is as follows.

First, in the case of an (not shown). (2)
Then, the communication control device 3 enters an incoming signal receiving state.

(3) When receiving an incoming call signal, it transmits an incoming call rejection signal once, and then interrupts the central processing unit 4.

(4) If the central processing unit 4 continues to be unable to receive calls, it issues the call rejection command 7 again. (5) As a result, the communication control device 3 repeats the operations of (2) and (3) above.

(6) On the other hand, if the central processing unit shifts to the incoming call ready state while the communication control device 3 is executing the incoming call rejection command 7, the central processing unit 4 The operation stop command 9 is issued.

(7) After the communication control device 3 stops executing the incoming call rejection command 7, it interrupts the central processing device 4.

(8) After the central processing unit 4 processes the interrupt in (7),
An incoming call acceptance command 8 is issued.

(9) Thereafter, the communication control device 3 enters the incoming signal receiving state, and when receiving the incoming signal, performs incoming call acceptance processing such as transmitting an incoming call acceptance signal.

After the processing is completed, the CPU 4 interrupts the processing. Next, in the case of the conventional X2l interface,
(10) When the central processing unit 4 issues a call rejection command 7 because the call cannot be received, the communication control unit 3 sets the command in the channel control word (not shown) corresponding to the line. do.

01) The communication control device 3 continuously transmits a controlled not ready (CNR) signal for a certain period of time, and then interrupts the central processing unit 4.

(12) The central processing unit 4 issues an incoming call rejection command again if the incoming call impossible state continues. 03) Accordingly, the communication control device 3 repeats the operation of 01) above.

(14) On the other hand, if the central processing unit shifts to the incoming call enabled state while the communication control device 3 is executing the incoming call rejection command, the same operations as in (6) to (9) above are performed.

In the case of the conventional system shown in Figure 2 above, each time a call rejection signal is transmitted or a controlled not ready signal is transmitted for a certain period of time, an interrupt is sent to the central processing unit 4. ing.

Therefore, the processing load on the central processing unit 4 increases. In particular, the central processing unit 4 issues an incoming call rejection command when the central processing unit 4 is operating near its processing capacity limit, so the above-mentioned interruption makes the central processing unit 4 even more difficult. will be forced into. The purpose of the present invention is to solve the above-mentioned problems, and to make it possible to process calls in an arbitrary manner within a communication control device without requesting instructions from the central processing unit each time a call cannot be received. The purpose is

Therefore, in the communication control system of the present invention, in a station system having a processing device that performs information processing and a communication control device that performs line control, in the communication control device, incoming calls are rejected in response to calls from the other end. When the above-mentioned processing device is notified by an incoming call rejection command that it is possible to do so, it immediately sends an end interrupt for the incoming call rejection command to the processing device, and thereafter transmits an incoming call rejection signal every time it receives a call, or continuously and a transmission processing means for transmitting a controlled no-not-ready signal, and the communication control device autonomously transmits the incoming call rejection signal or the controlled ready signal until the processing device issues an incoming call acceptance command, etc.・It is characterized by transmitting a not-ready signal.
The present invention will be explained below with reference to the drawings.

FIG. 3a shows an embodiment of the communication control method of the present invention when transmitting a call rejection signal based on the X2O interface, and FIG. 3b shows a controlled not-to-receive signal based on the X2L interface. 1 is an example of a communication control method according to the present invention when transmitting.

Note that, as in the case of the description of the conventional example described above, the figure expresses the processing of firmware within the communication control device in the form of a flowchart for the sake of simplicity. The reason why the present invention receives an interrupt after issuing an incoming call rejection command is that when the communication control device receives the incoming call rejection command, it sets the operation mode for this command (when receiving an incoming call signal, sends an incoming call rejection signal). ) and respond to the incoming call rejection command.

By returning a command completion interrupt, the next command (incoming call acceptance command) can be issued without issuing a stop command in response to the incoming call rejection command. Also, after the interrupt, other processing (in response to the command) Post-processing (processing for other lines, processing for processes other than communication lines) means that in response to an incoming call rejection command, a command completion interrupt is immediately performed, so other processes should be stopped during that time, and the interrupt This is to execute other processing after receiving the information.

The embodiment shown in FIG. 3a is configured to perform the following processing.

That is, (A) when the central processing unit 4 issues an incoming call rejection command 7 because the incoming call cannot be received, the communication control unit 3 issues this command as the channel control word (not shown) corresponding to the line in question. Set inside.

(B) Then, the communication control device 3 immediately sends an end interrupt in response to the above command to the central processing device 4, and enters an incoming signal receiving state.

(When receiving the O incoming call signal, the communication control device 3 transmits an incoming call rejection signal once to the line using the firmware.

(D) Thereafter, the incoming signal receiving state is entered without interrupting the central processing unit 4.

(E) Thereafter, the operations in (C) and (D) above are repeated every time an incoming call signal is received until an incoming call acceptance command, etc., which will be described later, is received.

(G) On the other hand, if the central processing unit 4 shifts to the state where the central processing unit 4 can receive a call while the communication control device 3 is executing the operations (6) and (D) above based on the incoming call rejection command 7, the central processing unit 4
issues an incoming call acceptance command.

G) The communication control device 3 sets the command in the channel control word (not shown) corresponding to the line, and stops the incoming call rejection signal transmission operations of (C) and (D) above. Thereafter, the communication control device 3 enters the incoming signal receiving state, and when receiving the incoming signal, performs incoming call acceptance processing such as transmitting an incoming call acceptance signal.

After the processing is completed, the CPU 4 interrupts the processing. (
) Note that although not shown in the drawings, it is also possible to stop the above-mentioned call rejection signal transmission operation by a command other than the call acceptance command, such as an operation stop command.

Next, in the case of the embodiment shown in FIG. 3b, the following processing is performed.

(J) When the central processing unit 4 issues a call rejection command 7 because the call cannot be received, the communication control unit 3 sets the command in the channel control word (not shown) corresponding to the line. do.

8 Then, the communication control device 3 immediately sends a termination interrupt in response to the above command to the central processing unit 4, and continuously sends a controlled not ready (CNR) signal to the line by means of the firmware. .

(1) On the other hand, if the central processing unit 4 transitions to a call-receiving state while the communication control device 3 is continuously transmitting the above-mentioned controlled-not-ready signal based on the incoming call rejection command 7, the central processing unit 4 issues an incoming call acceptance command.

The communication control device 3 sets the command in the channel control word (not shown) corresponding to the line, and also sets the command in the controlled not ready (
CNR) stop the continuous transmission operation of the signal.

N and below operate in the same manner as above.

(0) In addition, as in (1) above, the above Controlled Not Ready (CNR)
It is possible to stop the continuous signal transmission operation.

As explained above, according to the present invention, when receiving an incoming call rejection command, the communication control device immediately performs a termination interrupt, and thereafter autonomously performs an end interrupt until the central processing unit issues an incoming call acceptance command, etc. Since the incoming call rejection operation continues during the call period, no intervention from the central processing unit is required during that time.
Therefore, it is possible to improve the processing capacity and processing efficiency of the central processing unit that is in a state where it cannot receive calls.

[Brief explanation of the drawing]

Figure 1 is a connection configuration diagram when communicating via a circuit-switched network, Figure 2a is an example of a conventional communication control method when using an X2O interface, and Figure 2b is an example of a conventional communication control method when using an X2L interface. An example of the conventional communication control method, Part 3
FIG. 3A shows an embodiment of the communication control method of the present invention when using the X2O interface, and FIG. 3B shows an embodiment of the communication control method of the present invention when using the X2L interface.

Claims (1)

[Claims] 1. In a station system that has a processing device that performs information processing and a communication control device that performs line control, the processing device sends a message in the communication control device that indicates that the call cannot be received in response to a call from the other party's terminal. When notified by the command, it immediately sends a termination interrupt for the incoming call rejection command to the processing device, and thereafter sends an incoming call rejection signal every time it receives a call, or continuously sends a controlled call rejection signal.
has a transmission processing means for transmitting a not-ready signal;
A communication control system characterized in that the communication control device autonomously transmits the call rejection signal or the controlled not ready signal until the processing device issues an incoming call acceptance command or the like.