JPS59186450A - Communication control equipment - Google Patents

Abstract

PURPOSE:To make a request for recovery speedily, interrupt ineffective outgoing/incoming call operation, and shorten the holding time of a switching network, etc., when the switching network malfunctions by making a comparison with the ID signal of a called subscriber which is received during origination, comparison ACK signals coming after each ID signal of a calling subscriber which is received during termination, a vertical parity check during the reception of each signal, a check on a step-out error, a time-out check, etc. CONSTITUTION:An identification information ID signal and a connection completion signal ACK signal are all compared, and when all signals are coincident, a control circuit 10 informs a processor 1 of the completion of a normal connection with an opponent station through a channel control part 8. Further, when the ID signal or ACK signal are not coincident, the control circuit 10 sets a transmission line (T) 14 to ''0'' through a transmitting circuit 12, sends the recovery request to an exchange to interrupt the calling operation, and informs the processor 1 of the dissidence of the received ID signal or ACK signal. Further, the calling operation is interrupted as mentioned above in case of a step-out error during the reception of the receive signal, vertical parity error, time-out error, i.e. a failure of the reception of up to the ACK signal within a specific time, etc.

Description

[Detailed description of the invention] (Technical field) The present invention relates to a communication control device.

(Background technology) Conventionally, a communication control device receives a command from a host device and
When making a ``call'' to the other party's station, the following method was used. The higher-level processing unit (hereinafter referred to as CPU) instructs the communication control unit of the other party's number and issues a calling command. Upon receiving this command, ``the communication control device sets the transmission line (T) to ``1'' and issues one call to the exchange. Upon receiving this, the exchange sets the reception line (R) to ``1//vc'' to notify the communication control device that it has accepted the call request. As a result, the communication control device sends the destination number instructed by the CPU to the transmission line in bit series as a selection signal. A partner station is selected according to this selection signal, and when a communication line is set up with the partner station, the CP of the partner station is transmitted through the switching station.
The identification information (ID signal) of the partner station and the connection completion signal (ACK signal) are sent in bit series from U to the reception line of the communication control device via the communication control device of the partner station. Upon receiving this, the communication control device converts the bit-serial signal into parallel, and notifies the CPU to read it.

Furthermore, when a host device (CPU) receives an "incoming call" from a partner station through a communication control device, the following method is used. When there is an "incoming call" from the other party through the switching center, the switching center sets the reception line (R) to "1" and notifies the communication control device of the "incoming call."

In response, the communication control device sets the transmission line (T) to ``1'' to the switching center and transmits an incoming call acceptance signal (RACK signal) indicating acceptance of an incoming call in bit series.Next, the above-mentioned Caller identification information (ID signal) and connection completion signal (ACK signal) are sent from the switching center to the communication control device through the reception line (R).The communication control device converts the pinto series signals into parallel signals. , and notifies the CPU to read it.

The communication control device is usually connected to the CPU by a channel method, and commands are controlled by a channel control word (CCW). Taking "calling" as an example, the CPU first creates a CCW for calling instructions that includes address information of the CPU in which the other party's number is stored as the first CCW. "Call"
Add a sign to continue executing the fire instructions after the operation is complete. Next, as a second CCW, create a CCW for ID and ACK signal reception instructions that includes memory address information of the CPU that receives the ID signal and ACK signal and stores this signal,
Commands the communication control device to start operation.

In this way, both "outgoing calls" and "incoming calls" are connected to the receiving line (R).
The identification information (ID signal) and connection completion signal (ACK signal) sent from the communication control device were not judged at all and were transferred to the host device. Some kind of error occurred during this failed exchange process, and connection with the correct partner was not established, resulting in the ID being incorrect.

Even if an ACK signal is not obtained, it will be determined that there is an incorrect connection after the processing in the CPU has progressed considerably, and only at that point will the CPU issue a command for recovery processing to the communication control device to open the communication line. was.

As described above, the conventional communication control device does not discriminate the ID and ACK signals even though it receives them, and therefore has the drawback of delaying the recovery process in the case of an erroneous connection and placing an unnecessary load on the CPU.

In order to avoid the above-mentioned drawbacks, a memory or register is provided in the communication control device in advance, and the contents of the ID and ACK signal to be received when a correct connection is established are stored in the memory or register. There has been a method of comparing the ID and ACK signals received from the line (R) and performing recovery processing if they do not match, but this method has the drawback of increasing the cost of the communication control device.

(Problem of the Invention) An object of the present invention is to eliminate these drawbacks, reduce the load on a host device, and provide an economical communication control device.

The present invention performs a call operation in response to a call command from a host device, and when a partner station is selected and identification information (ID signal) and a connection completion signal (ACK signal) are returned, the above call command is issued. Subsequently, a command to compare identification information is issued to the chain.
Based on this command, the returned information is compared, and if they do not match, the call is stopped and the host device is notified of this fact. Also, when an incoming call is detected in response to an incoming call command from the host device, and the above return information is sent from the other party's calling station, following the incoming call command, the chain identifies information. A comparison command is issued and the comparison is made in the same manner as above, and if there is a mismatch, the incoming call is canceled and the host device is notified of this fact. This will be explained in detail below.

(Structure and operation of the invention) FIG. 1 shows a configuration diagram of a data communication system using a communication control device of the invention. The communication control device 5 is connected to a switching network 7 through a communication line 6, and is further connected to an input/output channel included in the communication control device 5 through an interface line 3 to a processing unit (CPU) and through an interface line 4 to a storage device (hereinafter referred to as M). 'EM) 2.

FIG. 2 is a configuration diagram of a communication control device to which the present invention is applied. A transmission line (T) 14 is connected to the transmission circuit 12 and transmits data according to instructions from the control circuit 10. Receive @
(R) 15 is connected to the receiving circuit 13, and converts the data sent from the switching network 7 into serial/parallel data in the receiving circuit 13 and passes it to the control circuit 1o. The channel control section 8 is connected to the storage device 2 through the interface line 4 and to the processing device 1 through the twisted interface line 3. The transfer character counting circuit 9 is used to count the number of characters transferred by the channel control section 8. The comparison circuit 11 is for comparing the transmitted and received characters with the contents of the storage device 2 through the channel control section 8.

First, the case where a call is made to a partner station will be explained. In FIG. 3, when the channel control unit 8 executes the calling channel control word j6, the control circuit 1o sets the transmission line (T) to put out. Upon receiving this, the exchange changes the reception line (R) to ゜　 to notify that it has accepted the call request. The receiving circuit 13 detects this and notifies the control circuit 1oVC.

In response, the control circuit 10 issues a data transfer request to the channel control unit 8 to transmit a selection signal indicating the partner station number.

The channel control unit 8 reads out the selection signal 19 by referring to the address in the storage device storing the selection signal 19 shown in the channel control word 16 for calling, and sends the selection signal 19 to the control circuit 10.
give it to As a result, the control circuit 10 sends the selection signal 19 to the exchange through the transmission circuit 2 and the transmission line (T) 14. A partner station is selected in response to this selection signal 19Vc, and thereafter identification information (ID signal) of the partner station and a connection completion signal (ACK signal) are sent from the exchange to the reception line (R) j5. Therefore, the receiving circuit 13 performs serial-to-parallel conversion and passes it to the control circuit 10. In general, the ID signal has a predetermined format, for example, a CR code, LF code, S■ code, * code, followed by a number (usually 7 digits), and finally a 10 sign. By the way, the control circuit 10 transmits the selection signal 19 through the transmission circuit 12 and the transmission line (T) 14 as described above, and the transmission has already been completed. When the control circuit 10 notifies the channel control section 8 of completion at this point, the channel control section 8 knows that the execution of the calling channel control word 16 shown in FIG. 3 has been completed. The calling channel control word 16 contains the next ID signal reception comparison channel control word 17.
Since a chain instruction has been issued to continue executing , the channel control unit 8 instructs the control circuit 10 to receive the ID signal and enters the receiving state.

The control circuit 10 in this state is notified by the reception circuit 13 of the reception of the above-mentioned ID signal. When the control circuit 10 is notified of the first code (CR code), it requests the channel control unit 8 to read out the comparison ID signal. The channel control unit 8 refers to the address in the storage device 2 where the comparison ID signal is stored, which is indicated in the ID signal reception comparison channel control word 17, and selects the first comparison code ( CR code). Here, the first code (CR code) received by the comparator circuit 11 is compared with the code (CR code) read from the storage device 2, and after confirming a match, it waits for reception of the second code, and then processes it. After receiving, all ID signals and ACK signals are compared, such as comparing the second received code (LF code) with the second code (LF code) in the storage device 2, and it is determined which one matches the second received code (LF code). If so, the control circuit 10 notifies the processing device 1 through the channel control unit 8 that the connection with the partner station has been successfully completed. Still ID signal or A
If the CK signals do not match, the control circuit JO sets the transmission line (T) 14 to "0" through the transmission circuit 12, sends a recovery request to the switching center, cancels the calling operation, and sends the signal to the processing device 1. Notifies you of a mismatch between the received ID signal or ACK signal.In addition to the mismatch of the above received signals, there is also a synchronization error when receiving the received signal, a vertical parity error, or a timeout error where the ACK signal could not be received within a certain period of time. Similarly to the above, it is also possible to cancel the calling operation and notify the processing device 1 including the detailed reason for the cancellation.

Next, the incoming call from the other station will be explained. When the channel control unit 8 executes the incoming call instruction channel control word 21 shown in FIG. 4 in response to a command from the processing device 1, the control circuit 10 becomes ready for incoming calls. In the case of an incoming call from the other station, the receiving line (R) 15 becomes ``1'' through the switching center, and the incoming call is notified to the control circuit 10.The control circuit 0 is the transmitting line (T).
After setting ゞゝ1〃, a data transfer request is issued to the channel control unit 8. The channel control unit 8 receives an incoming call acceptance signal (RACK) indicated in the incoming call instruction channel control word 21.
By knowing the address of the storage device 2 where the RACK signal is stored, the RACK signal is transferred to the read control circuit 10. The control circuit 10 transmits the RACK signal to the exchange through the transmission circuit 12 and the transmission line (T) 14, and then notifies the channel control unit 8 of completion. The channel control unit 8 receives an incoming call.
Since the instruction channel control word 21 contains a chain instruction, the next ID signal reception comparison channel control word 17 is executed. After this, the same operation as the above-mentioned calling operation is performed, and a report of the completion of the operation is notified to the processing device 1. In the case of an incoming call, there may be a case where there is not only one station but multiple stations at the other end. In this case, the received ID signal and ACK signal are held in the control circuit 10, so the ID signal is By chaining the required number of received comparison channel control words, it is possible to compare a plurality of prepared ID signals. The communication control device 5 usually uses a microprocessor and is controlled by a microprogram, and the comparison circuit 11 and the like are comprised of registers and arithmetic circuits in the microprocessor, and the microprogram determines the result of the comparison to find a match as described above. , to check for inconsistencies.

(Effects of the Invention) As explained above, the device of the present invention can compare called party ID signals received during a call, compare caller ID signals received during an incoming call, and compare caller ID signals received during an incoming call, and Comparison of incoming ACK signals, and vertical parity check when receiving each signal.
We perform synchronization error checks, timeout checks, etc., and if a malfunction of the switching network, etc. occurs, we promptly request recovery, cancel invalid call/receive operations, shorten the switching network's holding time, and It becomes possible to significantly reduce the load. This makes it possible to construct an economical and high-performance system, especially in a data communication system that connects to a switched line network.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing an example of a data communication system configuration including a communication control device to which the present invention is applied, Fig. 2 is a block diagram of a communication control device to which the present invention is applied, and Fig. 3 is a communication control device to which the present invention is applied. FIG. 4 is a diagram showing a group of channel control words when a communication control device to which the present invention is applied makes an incoming call. ■=Processing device, 2: Storage device, 3: Processing device interface line, 4: Storage device interface line, 5: Communication control device, 6: Communication line, 7: Switching network, 8: Channel control unit, 9: Transfer character Counting circuit, 10: Control circuit, 11
: comparison circuit, 12: transmitting circuit, 13: receiving circuit, 14:
Transmission line (T), 15: Reception line (R), 16 Channel control word for two callings, 17: Channel control word for ID signal reception comparison, 18: Storage area, 19: Selection signal storage area, 20
: ID signal storage area for comparison, 21: Channel control word for incoming call instruction, 232 Incoming call reception response signal storage area. Patent applicant Oki Electric Industry Co., Ltd. Patent application agent Megumi Yamamoto −

Claims (1)

[Claims] In a communication control device inserted between a host device and a communication line to control communication, a calling operation is performed in accordance with a calling command given from the host device, a partner station is selected, and identification information is returned. When the calling command is received, an identification information comparison command is issued by the chain, and means for comparing the received identification information returned by this command and notifying the higher-level device of the result, and when the comparison does not match. means for restoring the call, and responding to the call acceptance when an incoming call is detected according to the incoming call command given from the host device, and following the incoming call command when identification information is sent from the other party's calling station. A means for comparing received identification information actually sent to determine whether an identification information comparison command is issued by the chain and receiving a call is permitted, and notifying the higher-level device of the result, and when the comparison does not match. A communication control device comprising: means for restoring an incoming call.