JP3231351B2 - Communication control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication control device. As this type of communication control device, there is a LAN adapter that connects a device that is a main body of LAN communication with a LAN line.

[0002] When a LAN system is constructed, a terminal or server serving as a station host is connected to a LAN line via this type of device.

[0003]

2. Description of the Related Art When a failure occurs in a LAN line or any one of LAN adapters, the occurrence of the failure is notified from each LAN adapter to its own host.

As a result, each host is operated and its own L
A request to disconnect the line is given to the AN adapter, and the connection with the LAN line is disconnected.

After that, when the failure is recovered, the host of each station is operated again, and a request for line connection is given to its own LAN adapter.

[0006]

Even when no failure has occurred in the LAN adapter of the own station or when the failure has been recovered immediately, the operation of the station host for disconnecting from the LAN line and reconnecting to the LAN line is performed. Was carried out, resulting in interruption of business.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional circumstances, and an object of the present invention is to provide a LAN adapter capable of limiting a station host to be operated when a failure occurs to a necessary one. is there.

[0008]

In order to achieve the above object, a communication control apparatus according to the present invention is configured as shown in FIG.

In FIG. 1, data transfer performed with a requester 10 of LAN communication is controlled by a first control means 12, and the first communication means 16 performs LAN communication (data communication) via a LAN line 14. ) Is performed.

[0010] The procedure control of the LAN communication (data communication) is performed by the second control means 18, and the occurrence of the LAN communication failure is detected by the detection means 20.

When the failure is detected by the detecting means 20, the LAN communication (data communication) is interrupted by the interrupting means 22, and the transmission is continued until a certain period of time elapses or the fault is recovered. Means 24 to LA
Data is repeatedly transmitted to N lines.

When data transmission is repeated until a predetermined time has elapsed since the occurrence of the failure is detected, LAN communication (data communication) for diagnosis is performed by the second communication means 26.

Further, diagnostic LAN communication (data communication)
State of the LAN line 14
Is determined by the determination means 28 (ie, whether the failure has occurred in the communication control device of the local station or has occurred on the side of the LAN line 14). when it is confirmed from the result, the determination result is LAN
The communication request source 10 is notified from the notification means 30.

[0014] When the failure is recovered from the time when the occurrence of the failure is detected until a predetermined time elapses, or when the occurrence of the failure is not confirmed from the determination result,
When the LAN communication (data communication) is restarted by the restart means 32 and the occurrence of a failure is confirmed from the determination result , the LAN communication (data communication) is started.
The line connection with the line is disconnected.

[0015]

According to the present invention, data transmission is repeated for a certain period of time after the occurrence of a failure is confirmed, and when the restoration of the failure is confirmed during that time, LAN communication is resumed.

If the failure is not recovered by repeating data transmission for a certain period of time, the diagnostic LAN
Communication is performed and whether or not a failure has occurred and its location ( LAN
It is checked whether a failure has occurred on the line 14 side or a failure has occurred on the communication control apparatus side.

At this time, if the occurrence of the failure is not confirmed, the LAN communication is restarted. If the occurrence of the failure is confirmed, the fact and the location of the failure are notified to the requester 10 of the LAN communication. Is done.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the communication control means according to the present invention will be described below with reference to the drawings.

FIG. 2 illustrates the configuration of the embodiment.
In the figure, a LAN adapter 40 as a communication control means is shown.
Is inserted between the CPU 10 of the station host, which is the request source of the LAN communication, and the LAN line 14.

The LAN adapter 40 has an interface section 12 as first control means, and LAN communication (data communication).
And a LAN control LSI 16 as a first communication unit for performing LAN communication via the LAN line 14, and a LAN control unit 18 as a second control unit for controlling the communication procedure.
These are given control instructions from the MPU 42.

The interface unit 12 is connected to the CPU 1
0, and controls data transfer with the CPU 10.

The LAN control LSI 16 is connected to the LAN line 1
4 and performs LAN communication via the LAN line 14.

Furthermore LAN protocol part 18 is provided between the interface unit 12, LAN control LSI 16, L
It performs procedure control of AN communication (data communication) .

Here, when the occurrence of a fault is detected (detection means 20), the occurrence of the fault is notified from the LAN control LSI 16 to the interrupt processing unit 44, and the occurrence of the fault is confirmed by the interrupt processing unit 44. And LAN communication (data communication) are interrupted (interruption means 22).

At that time, the timer unit 50 is
Is activated, and when the timer 50 times out, the diagnostic processing unit 52 is activated.

FIG. 3 is a flowchart illustrating the operation of the interrupt processing unit 44, and indicates whether the diagnostic processing unit 52 has been activated (step 300) and whether a failure has occurred (step 302). , The timer unit 50 is activated (step 304).

When the occurrence of a fault is notified from the LAN control LSI 16, the diagnostic processing unit 52 has not been activated,
It is determined that a failure has occurred and the timer unit 50 has not been activated (step 300, step 300).
302, 304), whereby the timer unit 50 is activated and its timer operation is started (step 306).

Thereafter, when the transmission data at the time of occurrence of the fault
It is repeatedly transmitted to the line 14 (step 308, transmitting means 24), and when the restoration of the failure is confirmed on the way (NO in step 302), normal LAN communication (data communication ) is restarted (step 310, restarting means). 32).

FIG. 4 is a flowchart illustrating the operation of the timer unit 50. When the elapse of the timer time is confirmed (YES in step 400), the diagnosis flag is turned on (step 402), and the diagnosis processing unit 52 is activated. Is started.

When the interrupt processing section 44 confirms that the diagnosis flag is ON (YES in step 300), the control is transferred to the diagnosis processing section 52 (step 312).

In FIG. 5, the operation of the diagnosis processing section 52 is described in a flowchart. First, it is determined whether the diagnosis processing has already been started (step 500).

At the time of startup, the diagnostic processing has not been started (NO in step 500). Therefore, the diagnostic processing flag indicating the start is turned on (step 502), and after the diagnostic mode is set in the register, the diagnostic data is transmitted to the LAN. Line 1
4 (steps 504, 506).

After the next time, it is confirmed that the diagnostic processing has already been started (YES in step 500),
It is determined whether the transmission of the diagnostic data has been performed normally (step 508), and whether the response to the data has been normally received (step 510) (second communication means 26, determination means 28). .

When the normal operation of the diagnostic data transmission is confirmed (YES in step 508), the CPU 1 notifies the CPU 1 of the transmission completion indicating the normal operation of the LAN adapter 40.
0 (step 512).

If the normal operation of response reception is confirmed (YES in step 510), the LAN adapter 4
0 and a notification indicating that a failure has not occurred in the LAN line 14 (it is considered that a failure has occurred in the LAN adapter 40 of another station) is sent to the CPU 10, and the diagnostic processing flag and the diagnostic processing flag are output. Normal LAN with OFF
The communication (data communication) operation is restarted (step 51).
4. Resuming means 32).

Further, when the transmission of the diagnostic data is not performed normally (NO in step 508), a notification indicating that a failure has occurred in the LAN adapter 40 is sent to the CP.
If the response is not normally received (NO in step 510), the LAN line 14
A notification indicating that a failure has occurred on the side of the CPU 10
(Step 516, notification means 3
0).

The CPU 10 notifies them (step 5
12, 516), the failure occurrence and its occurrence location (the local LAN adapter 40 or LAN line 14) are displayed and output to the operator.

At this time, the line is disconnected by the input operation.
When the failure is recovered after the request to the N adapter 40, the request for the line connection is sent to the LAN adapter 4
0 is given by an input operation.

Therefore, according to the present embodiment, the stations requiring the host operation of disconnecting the line and connecting the line are limited to those in which a failure has occurred in the LAN adapter 40 (except when a failure has occurred in the LAN line 14). ).

The local station's LAN adapter 40 or LAN
Even if a failure occurs on the line 14, if the failure is recovered while the transmission retry is repeated, the data transmission up to that point is automatically restarted.

For this reason, the interruption of the work due to the LAN communication can be localized, and as a result, the decrease in the work efficiency can be minimized.

[0042]

As described above, according to the present invention, even if a communication failure occurs, if the recovery is confirmed within a predetermined time, the data communication up to that time can be automatically restarted, and Only when the fault that occurred in the communication control unit of the station or the LAN line did not recover within a certain period of time, the fault occurrence and its location are notified to the station host. As a result, the line disconnection and line connection operations are performed. You can limit the hosts to perform.

Therefore, the stations where the operation is interrupted can be localized to the minimum necessary, and therefore, the decrease in the operation efficiency can be minimized.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of the present invention.

FIG. 2 is a diagram illustrating the configuration of an embodiment.

FIG. 3 is a flowchart illustrating an operation of an interrupt processing unit.

FIG. 4 is a flowchart illustrating an operation of a timer unit.

FIG. 5 is a flowchart illustrating an operation of a diagnosis processing unit.

[Description of Signs] 10 CPU 12 interface unit 14 LAN line 16 LAN control LSI 18 LAN procedure unit 40 LAN adapter 42 MPU 44 interrupt processing unit 50 timer unit 52 diagnostic processing unit

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-171253 (JP, A) JP-A-62-207041 (JP, A) JP-A-54-33638 (JP, A) JP-A-4- 181835 (JP, A) JP-A-4-1722843 (JP, A) JP-A-4-262642 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04L 12/28-12 / 44

Claims (1)

(57) [Claims] First control means for controlling data transfer performed between the claim 1. A LAN communication request source, a first communication means for performing LAN communication via the LAN, the procedure control of LAN communication and second control means for performing, detecting means for detecting a failure of LAN communication, and interrupting means for interrupting the LAN communication when occurrence of a failure is detected for a period of time from when the occurrence of failure is detected A transmission means for repeatedly transmitting data to the LAN line until the time elapses or until the fault is recovered; and a second means for performing a diagnostic LAN communication when a certain time has passed since the occurrence of the fault was detected. and second communication means, determining means for determining whether the state of the LAN communication for diagnostic presence and the failure of the failure has occurred on the side of the LAN, the occurrence of failure determination result And notifying means for notifying the determination result to the LAN communication request source when it is check the options, the occurrence of or failure when the the disorder before the occurrence of the fault has passed a certain time from the time it is detected restored Resuming means for resuming the LAN communication when the failure is not confirmed from the determination result, and when the occurrence of the fault is confirmed from the determination result, the LAN means
A communication control device characterized by disconnecting a line connection with a line .