JP3342507B2 - LAN control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for controlling a local area network (LAN) in which various devices such as a plurality of independent personal computers are interconnected.

[0002]

2. Description of the Related Art Local area networks (LANs)
Is configured so that devices such as computers, terminal devices, and personal computers distributed in a limited area can be interconnected for communication. This LA
Some devices such as a personal computer (hereinafter abbreviated as “PC”) constituting the N have a resume function.

The resume function is provided with a battery backup function. When the power is turned off (by a power switch or software), the contents of the work are stored in a memory (VRAM, RAM, etc.), and then the power is turned on. Is a function to return to the state before the power was turned off when is turned on. This is a convenient function that minimizes battery consumption and eliminates the need for system startup in notebook-type or laptop-type battery-powered personal computers.

Powering off in this case does not mean that the power is completely turned off, but that the main circuits such as the CPU and the memory are in a sleep mode (a state where only the minimum necessary power is supplied). It is.

[0005]

Normally, a device (a personal computer or the like) constituting a LAN transmits packets to a device that has established a virtual circuit periodically and waits for a response.
When there is no response for a certain period of time or longer, the virtual line partner device has a function of disconnecting the virtual line by determining that the device of the virtual line partner cannot respond due to some reason, for example, reset. Even if the device does not have such a function, if there is no response notifying that the packet has been normally received when the packet is transmitted, the device retransmits the packet and disconnects the virtual circuit when there is no response.

For this reason, in a device having a resume function, if the power is turned off and the sleep mode is entered by the resume function, the virtual line is disconnected because it cannot respond to a request from the device that has established the virtual line. The disadvantage is that the resume function cannot be used.

When data is transmitted and received using the LAN, the LAN interface sends an interrupt request signal to the CPU of the device. When the CPU receives the interrupt request signal, the CPU interrupts the program in progress to interrupt the LAN. Execute instructions from the interface. However, if the device is in the sleep state due to the above-described resume function, the CPU cannot receive the interrupt signal, and the communication partner determines that the device is in some abnormal state, and A communication error occurs because the virtual line to the network is unilaterally disconnected.

[0008] The present invention has been made in view of the above points, and has as its object to provide a LAN control method that can utilize a resume function of a personal computer or the like.

[0009]

SUMMARY OF THE INVENTION A LAN control method according to the present invention is characterized in that when a device having a resume function is turned off and enters a sleep mode, the device has a virtual circuit established on a network. On the other hand, a packet having a message notifying that a sleep mode is to be transmitted is transmitted, and a network environment that is the same as before the power is turned off after the power is turned on is obtained. Further, the message notifying that the sleep mode is to be entered may include data for causing another device to execute its own network processing function instead.

[0010]

[0011]

According to the present invention, when a device having a resume function has established a virtual circuit with another device on the LAN, when the power is turned off and the device enters the sleep mode, the other device is placed in the sleep mode. By sending a message notifying that the user is going to enter, the network environment can be preserved between the time when the power is turned off and when the power is turned on.

[0012] In addition, by including data for causing other devices to execute their own network processing functions instead in a message notifying that the device is to enter the sleep mode, the other devices can automatically notify other devices when the power is turned off. Can be executed instead.

[0013]

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 2 is a configuration diagram showing the overall class form of a typical LAN. As shown in FIG.
Are connected to the central control station 5. And personal computer 1
Has a resume function, that is, with a battery backup function.
It has a function of storing data such as RAM and RAM.

Assuming that the personal computer 1 has established a virtual line with the personal computers 2 and 3 at present as shown in the signal sequence of FIG.
Are sending packets to each other periodically and waiting for a response from the other party.

When the power switch of the personal computer 1 having the resume function is turned off in this state, the CP of the personal computer 1 is turned off.
An interrupt is input to U and a stop process is started. In the stop process, the personal computer 1 transmits a packet 6 for notifying the personal computer 2 and the personal computer 3 of a destination address, a source address, and a message to enter the sleep mode as shown in FIG.

The personal computer 2 and the personal computer 3 that have received the packet 6 know that the personal computer 1 has been turned off and have entered the sleep mode, and stop transmitting to the virtual line established with the personal computer 1. . However, in this case, the virtual line with the personal computer 1 is kept. Then, the personal computer 1 that has entered the sleep mode is performing the resume function.

Next, when the power switch of the personal computer 1 is turned on, the personal computer 1 simultaneously transmits a packet 7 for notifying a message indicating the activation as shown in FIG. When the personal computer 2 and the personal computer 3 receive this message, they release the virtual line with the personal computer 1 and resume transmission / reception with the personal computer 1. By performing such processing, the resume function of the personal computer 1 can be realized without the user of the personal computer 1 being completely conscious.

In the above embodiment, when the power of the personal computer 1 is turned off, a packet 6 notifying a message to enter the sleep mode is transmitted to the personal computers 2 and 3 with which the virtual circuit is established. , 3 do not transmit / receive packets because they know that the personal computer 1 is in the sleep mode.
Since it does not know this, a connector request or broadcast-type transmission may be performed to the personal computer 1. In this case, since there is no response from the personal computer 1 to the personal computer 4, an error occurs in the network. Therefore, it is necessary to avoid this error.

Therefore, when the personal computer 1 transmits a packet informing the personal computers 2 and 3 of a message to enter the sleep mode, the first packet transmitted to the personal computer 2 as shown in FIG. Add a message indicating an alternative processing request. When receiving the packet 6 ′, the personal computer 2 performs a response process in place of the personal computer 1 when receiving the broadcast type packet from the personal computer 4.

For example, when the personal computer 4 attempts to start up a network with the name of the personal computer 1 while the personal computer 1 is in the sleep mode with the power turned off,
Cannot respond, the PC 2 returns a response to the PC 4. When the personal computer 4 attempts to establish a virtual circuit with the personal computer 1, it transmits a broadcast type packet and waits for a response from the personal computer 1.
Since the personal computer 1 cannot respond, the personal computer 2 transmits a packet indicating that “the personal computer 1 is in the sleep state” to the personal computer 4.

In this way, when the personal computer 1 is in the sleep mode, it is possible to prevent an error from occurring in the network. In the above embodiment, an example in which the present invention is applied to a LAN in which only a plurality of personal computers are connected to a network has been described for the sake of simplicity, but devices other than personal computers (workstations, displays, printers, fax machines, etc.) are described. It is needless to say that various types of terminal devices including the above may be connected.

Next, another embodiment of the present invention will be described with reference to FIG. FIG. 6 is a block diagram showing a main part of a device such as a personal computer having a resume function in this embodiment.

This device has a CPU 1 as a central processing unit.
0, a ROM 11 serving as a program memory, a RAM 12 serving as a data memory, and a power supply unit (P
SU) 13, power switch 14, interrupt controller 1
5, a resume controller 16, a LAN interface 17, and a system bus 18 for connecting them. The LAN interface 17 is connected to another device such as a personal computer via a LAN network (not shown) and the central control station shown in FIG.

The interrupt request line from the LAN interface 17 is connected to the CPU 10 through the resume controller 16 and the interrupt controller 15. In this embodiment, when transmitting / receiving data using the LAN, the transmission signal TxD
And receives a reception signal RxD from another device.

When the power switch 14 is turned on, the power unit 13 outputs the DC voltage Vcc, and the CPU 10, R
Although a specified voltage is supplied to the OM 11, the RAM 12, and the like, when the power switch 14 is turned off, the resume controller 16 functions to supply a minimum necessary voltage to main circuits such as the CPU 10 and the RAM 12. To enter sleep mode.

In this sleep mode, if there is a communication request from another device connected to the network,
The LAN interface 17 receives it and sends an interrupt request signal to the resume controller 16. When the resume controller 16 receives the interrupt request signal, it temporarily holds the interrupt request signal therein, sends a command to the power supply unit 13 to release the sleep state, turns the power supply on, and supplies a normal voltage to each circuit. .

After the system processing is resumed (after a certain period of time required for resuming the device to return to the normal operation state), the interrupt request held by the resume controller 16 is sent to the CPU 10 as an interrupt signal IRQ. send. The resume controller 16 has a status register so that the CPU 10 can read the cause of the resume. The two factors are an interrupt signal due to a communication request from another device connected to the LAN network and turning on the power switch 14.

When the CPU 10 receives the interrupt signal IRQ, it interrupts the program in progress and executes the instruction from the LAN interface 17. At the end of the series of interrupt processing, the status register of the resume controller 16 is read, and the state before the interruption (sleep or normal power switch ON) is determined. 16 is returned to the original sleep state.

As a result, the resume controller 1
Reference numeral 6 sends a command to the power supply unit 13 to cause the power supply unit 13 to have a minimum necessary power supply state. In addition, the interrupt controller 15 is also connected to a plurality of interrupt lines from various other peripheral devices, and receives an interrupt signal therefrom.

FIG. 7 is a block diagram showing a main part of an apparatus according to an embodiment in which the above embodiment is partially modified. The functions of a resume controller and an interrupt controller are different from those of the above-described embodiment.

Resume controller 1 of this embodiment
Reference numeral 6 'denotes an interrupt signal input line (including an interrupt request from the LAN interface 17 and an interrupt line from another peripheral device) and an output line (INT0 to INT3) capable of inputting a plurality of interrupt request signals. ), And a master register is provided for each input signal line to specify whether to enable resume. It is assumed that the register can be operated from the CPU 10.

Then, just before the device enters the sleep operation, this register is operated to accept only necessary interrupt signals from a plurality of interrupt request signals during sleep and mask unnecessary interrupts. Also, when a plurality of interrupts are permitted and are simultaneously input, the interrupt controller 15 'determines the priority of the interrupt. Other operations are the same as those of the above-described embodiment, and the description thereof will be omitted.

[0034]

As described above, according to the first aspect of the present invention, a personal computer having a resume function is connected to a LAN.
Turn off the power by sending a message to other computers that they will enter sleep mode when they turn off and enter sleep mode if a virtual circuit has been established with the other computer above. The network environment can be preserved even after the power is turned on afterwards, and the user can utilize the original resume function without being aware of it.

According to the second aspect of the present invention, the power supply is turned off by including, in the message notifying that the sleep mode is to be entered, data for causing another personal computer to execute its own network processing function instead. Sometimes, by having another personal computer execute its own network processing function instead, it is possible to process the broadcast packet of the other personal computer and to avoid an error in the network.

[0036]

[Brief description of the drawings]

FIG. 1 is a signal sequence diagram showing an operation of an embodiment of the present invention in the LAN shown in FIG.

FIG. 2 is a configuration diagram showing an example of the overall network form of a LAN to which the present invention is applied.

FIG. 3 is a view showing a data frame of a packet for notifying a message to enter a sleep mode when the personal computer 1 having the resume function shown in FIGS. 1 and 2 is turned off.

FIG. 4 is a diagram showing a data frame of a packet for notifying a message indicating activation when the personal computer 1 is turned on.

FIG. 5 is a diagram showing another example of a data frame of a packet for notifying a message that the personal computer 1 enters a sleep mode.

FIG. 6 is a block diagram showing a main part of a device such as a personal computer having a resume function according to another embodiment of the present invention.

FIG. 7 is a block diagram showing a main part of a device according to still another embodiment in which the embodiment of FIG. 6 is partially modified.

[Explanation of symbols]

1-4 PC 5 Central control station 6
6 ', 7 packets 10 CPU 11 ROM 12 R
AM 13 Power supply unit 14 Power switch 15, 15 'Interrupt controller 16, 16' Resume controller 17 LAN interface

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04L 12/28 H04L 12/40 G06F 1/00

Claims (2)

(57) [Claims] When a device having a resume function is turned off and enters a sleep mode, a packet having a message notifying another device that has established a virtual circuit on a network that the device will enter a sleep mode. Transmitting a network connection, and obtaining a network environment that is the same as before the power is turned off even after the power is turned on.
N control method. 2. The method for controlling a LAN according to claim 1, wherein the message notifying the user to enter the sleep mode includes data for causing another device to execute its own network processing function instead. LAN control method.