JP2001016221A - Network system, electronic equipment and power supply control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To allow equipment in a power saving state to be switched into an operating state through remote control by other equipment in the case that the equipment are interconnected by a specific bus such as an IEEE 1394 bus. SOLUTION: At interruption of power, a power supply control circuit 6 of equipment supplies power only to a physical layer control circuit 8 to set the power saving state. In the case that the equipment receives a command from other equipment via an IEEE 1394 bus, the physical layer control circuit 8 compares a node ID attached to the command with its own node ID stored in a node ID storage section 81 to discriminate whether or not the command is addressed to the device. In the case of the command addressed to the equipment, the physical layer control circuit 8 gives an instruction to the power supply control circuit 6 to execute supply of power to all protocol layers. Thus, this equipment can be used in an operating state while being switched from the power saving state without the need for direct control of this electronic equipment in the power saving state by having only to send the command from the other equipment to this device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for connecting a plurality of electronic devices such as a personal computer and a digital audio-visual device (digital AV device) to a specific bus (IEEE13).
The present invention relates to a network system that is networked using an H.94 bus, an electronic device used in the network system, and a power control method for the device.

[0002]

2. Description of the Related Art IEEE 1394 bus (IEEE Std 1394-1)
995, Standard for a High Performance Serial Bus)
Is a serial bus used for exchanging digital data between a plurality of digital devices or forming a network for controlling a plurality of digital devices with each other.

[0003] The IEEE1394 is used for a serial bus.
In addition to the bus, there is a USB bus (Universal Serial Bus). The data transfer rate of the IEEE 1394 bus is 400 Mbps at the maximum, while the data transfer rate of the USB bus is 12 Mbps at the maximum. Not suitable for transmission media such as large video data.
Therefore, it is now common to use an IEEE 1394 bus to form a network of AV devices. Since the structure of the network formed by the IEEE 1394 bus is a branch type, a certain digital device may mediate data transmission between two other digital devices. Therefore, just because the digital device has been used does not mean that all functions of the digital device can be stopped.

Here, not only is a case where a certain digital device is disconnected from the network during data transmission, but also if a certain digital device is accidentally turned off to save power, for example ( When the power is turned off including the physical layer), the data transmission path is interrupted by the digital device, and the data is not transmitted to other digital devices thereafter. In addition, at that time, the bus reset operates, and the network is reconstructed only with the device located at the upper level of the digital device. afterwards,
When the power of the digital device is turned on, a bus reset is activated again to return to the original network configuration.

[0005]

As described above, the IE
When the power of a digital device compatible with the EE1394 bus is turned off, the functions of the entire device are stopped. For this reason, if a certain digital device is in the middle of other devices that are transmitting data, if the power is accidentally turned off, data transmission is interrupted halfway, and a bus reset occurs. There is such a disadvantage.

Therefore, when a certain digital device on the network is not used, it is necessary to supply a minimum necessary power only to the physical layer of the device and to set a power saving state so that data transmission is not interrupted. It is considered. However, in such a state, when using the original function of the digital device, the user has to go directly to the place where the digital device is installed to perform a restart operation, which is very troublesome. There was such a problem.

The present invention has been made in view of the above points, and when a plurality of devices are connected by a specific bus such as an IEEE 1394 bus, a device in a power saving state is remotely controlled from another device. It is an object of the present invention to provide a network system, an electronic device, and a power supply control method that can be switched to an operation state by a simple operation.

[0008]

SUMMARY OF THE INVENTION According to the present invention, when a plurality of electronic devices are connected to a specific bus such as an IEEE 1394 bus to form a network, when a certain electronic device is turned off, only a physical layer is provided. By supplying power to the power saving state, when using the electronic device, by sending a command from another electronic device via the specific bus,
The power supply to all the protocol layers including the physical layer of the electronic device in the power saving state is executed.

Thus, even if the electronic device in the power saving state is not directly operated, the power supply to each layer of the electronic device is executed and switched to the operating state by the operation of merely sending a command from another electronic device. be able to.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example of a network system formed by an IEEE 1394 bus. In the figure, a is a personal computer (PC), b is a set-top box (STB), c is a digital video tape recorder (DVTR), d is a DVD-RAM device, e is a printer (Printer), and they are all IEEE1.
An electronic device having a data transmission function using a 394 bus.

When these are referred to as node names, c,
Since d and e correspond to the ends of the tree, they are called leaves, b is a branch, and a is a root. Such a configuration is generally called a branch type,
Control instructions and data such as c to b and a to c can be transmitted to each other (the relationship of abc connection is a daisy chain connection).

In this example, the set-top box of b will act as an intermediary for data transmission between the personal computer of a and the digital video tape recorder of c and the DVD-RAM device of d, thus When turning off the power of this set-top box b,
It is necessary to consider the data transmission between the personal computer a and the digital video tape recorder c and the DVD-RAM device d.

Therefore, for example, when the power of the set-top box b is turned off, the power is supplied only to the physical layer so that the data transmission is not interrupted. deep. However, in order to switch the device from the power saving state to the normal power supply state and to the operation state, the user must go directly to the set-top box b and operate.

In order to solve such a problem, according to the present invention, in a device corresponding to the IEEE 1394 interface, in the power saving state, power supply is left only to the physical layer, and some request to the electronic device is received from another device. If there is, power is supplied to all layers of the electronic device, and the electronic device is sequentially activated from the physical layer level to the upper layer level. That is, the electronic device in the power saving state is automatically returned to the normal power state by a remote operation from another device on the network and switched to the operating state. Hereinafter, this point will be described in detail.

FIG. 2 is a block diagram showing the configuration of an electronic device according to one embodiment of the present invention.

The electronic device according to the present embodiment has a CPU
1, a system memory 2, a display controller 3, a power supply microcomputer 4, a power supply 5, a power supply control circuit 6, a link layer control circuit 7, a physical layer control circuit 8, and a power button detection unit 9. It is assumed that the electronic devices a to e described in FIG. 1 have the configuration in FIG.

The CPU 1 controls the entire electronic device, and executes and controls various control programs stored in the system memory 2.

The system memory 2 stores various control programs executed and controlled by the CPU 1 and various data used for executing the programs. The control program stored in the system memory 2 and executed and controlled by the CPU 1 includes a 1394 bus power management unit 20, an application layer control unit 21, a middleware layer control unit 2
2 and a transaction layer control unit 23.

The 1394 bus power management unit 20 is an IEEE
This is a program for managing power supply to a protocol layer configured to control data transmission using the 1394 bus. This protocol layer is generally
The electronic device is composed of five layers, a physical layer, a link layer, a transaction layer, a middleware layer, and an application layer. The software is controlled by a unit 21, a middleware layer control unit 22, and a transaction layer control unit 23. The other two layers, a physical layer and a link layer, are provided with a link layer control circuit 7 described later.
And the physical layer control circuit 8 controls the hardware.

The display controller 3 is a device that controls the output of a user interface in the electronic device, and controls display on a display 31 such as an LCD (Liquid Crystal Display) or a CRT (Cathode-ray tube).

The power supply microcomputer 4 is a device for managing the supply of power for operating the electronic device by driving and controlling the power supply 5. The power supply 5 controls the entire electronic device under the control of the power supply microcomputer 4. It is a device that performs power supply. The power supply control circuit 6 is a device that switches between supply and cutoff of power from the power supply 5 to the link layer control circuit 7 and the physical layer control circuit 8.

The link layer control circuit 7 is an IEEE 1394
A circuit for controlling a link layer in a protocol layer configured to control data transmission using a bus,
The physical layer control circuit 8 is a circuit for controlling a physical layer in the protocol layer.

The power button detection unit 9 is a device that controls the input of a user interface in the electronic apparatus, and detects that the power button 91 is pressed by the user.
This is notified to the CPU 1.

Here, when the electronic device is in the power saving state, the physical layer control circuit 8 performs a series of processes from a request from another device on the network to a restoration to the normal power supply state. Assumed to be performed. This physical layer control circuit 8
Is a controller LSI for the physical layer, and includes a node ID holding unit 81 for holding a node ID assigned to the device at the time of system construction (at the time of bus reset). The node ID is an identification number uniquely assigned to each electronic device (node) connected to the IEEE 1394 bus.

The method of assigning node IDs will be briefly described. First, the node that wins the arbitration at the time of constructing the system has the node ID “0”. The node having the node ID “0” transmits a self ID packet indicating that the node has the node ID “0”. Since this packet is broadcast, all nodes know that node ID "0" has been assigned. Then, the node that has won the arbitration next has the node ID “1”. The node having the node ID “1” sends a self ID packet indicating that the node has the node ID “1”, and sends the node ID to other nodes.
Notifies that D "1" has been assigned. In this way, all nodes on the network
The same procedure as described above is repeated until the transmission of the packet is completed.

Arbitration is performed such that the order of transmitting the self-ID packets is leaf first, branch next, and root last. The root is always the last
It sends out a D packet and has the largest node number. Up to 63 nodes can be connected to one IEEE 1394 bus. The bus can be expanded up to a total of 1023 buses. That is, devices of up to 1023 × 63 nodes can be connected.

FIGS. 3 and 4 are diagrams showing the flow of transmission data in the IEEE 1394 protocol layer. FIG. 3 is a diagram showing a data flow when the own device is executing data transmission, and FIG. 4 is a diagram showing a data flow when the own device is mediating data transmission between other devices. FIG.

As shown in FIGS. 3 and 4, this IEEE
The protocol layer of E1394 is the application layer 10
1. Middleware layer 102, transaction layer 10
3, the link layer 104 and the physical layer 105. Of these, the lowest physical layer 105 is the IEEE
This layer controls a physical / electrical interface with the 1394 bus, and performs automatic recognition of node connection, arbitration of bus use right between nodes on the bus, and the like. From FIG. 4, it can be seen that if even this physical layer 105 is functioning effectively, data transmission between other devices can be mediated.

The link layer 104 is responsible for addressing, data check, transmission / reception of buckets (transmitted and received by its own device, not mediation), and cycle control for isochronous (synchronous) transfer. Is a layer that controls processing related to asynchronous (asynchronous) data.

Next, the operation when the electronic device in the power saving state is restored to the normal power supply state by operation from another device will be described.

FIG. 5 is a flowchart showing the operation of the power supply control process in the electronic apparatus of the present invention.

When the power of this apparatus is turned off by pressing the power button 91, at least power can be supplied only to the physical layer in order to mediate commands and data from another apparatus to another apparatus. Power saving state (step S11).

Here, when the user operates a certain button (for example, a “disc playback” button in the case of a DVD device) in order to perform some operation on the electronic device in the power saving state from another device, An asynchronous command with the node ID of the electronic device to be operated is broadcasted to each electronic device on the network. Although the operated electronic device is in the power saving state, since only the physical layer is supplied with power as described above, commands and data from other devices can be transferred. Whether the received command is a command for itself can be determined by referring to the node ID added to the command.

That is, when the device in the power saving state acquires a command from another device connected to the network (step S12), it is determined whether the node ID added to the command matches its own node ID. It is determined whether or not it is (step S13). Specifically, in the power saving state, power is supplied only to the physical layer control circuit 8 by the power supply control circuit 6 shown in FIG. 2, and the physical layer control circuit 8 receives a command sent from another device. , And compares the node ID added to the command with the node ID of the device held in the node ID holding unit 61,
It is determined whether both node IDs match (step S13).

If the node IDs of the two match, that is, if it is confirmed that the command is directed to itself (Yes in step S13), the physical layer control circuit 8 issues an instruction to the power supply control circuit 6 to control the link layer control. Circuit 7 and CPU
1 is executed. As a result, the power saving state in which only the physical layer has been supplied is restored to a state in which power can be supplied to all layers of the protocol layer, that is, a normal power supply state (step S14).

At this time, the physical layer activates the inactive link layer corresponding to the upper layer and passes the command, and the link layer activates the inactive transaction layer which is the upper layer to execute the command. hand over. In this way, by sequentially transmitting the received command to the upper layer, all layers of the entire device are activated, and the command sent to the device is normally interpreted and processed. can do. Thereafter, the device operates in the power supply state as usual, and other devices can operate the device and send various data.

On the other hand, if the node ID of the command sent from another device does not match its own node ID in step S13, the command at that time passes through the physical layer of the device and is transmitted to another device. (Step S15). In this case, the device remains in the power saving state.

More specifically, in FIG. 1, for example, it is assumed that the power supply of the set-top box b is turned off. At this time, power is supplied only to the physical layer, and the physical layer is in a power saving state (non-operating state). Here, it is assumed that the user operates the personal computer a and transmits some command. This command is transmitted to each electronic device connected via the IEEE 1394 bus. When the physical layer controller in the set-top box b receives the command, it compares the node ID added to the command with its own node ID. If the two node IDs match, it is an operation command for itself. And instructs all layers to supply power. As a result, the set-top box b is restored from the power saving state to the normal power supply state, and becomes an operating state.

As described above, when using the electronic device in the power saving state, even if the user goes directly to the electronic device and does not perform the restarting operation, the user can use the electronic device in the operating state connected to the network. , The device can be returned to the normal power supply state and the device can be easily operated.

In this embodiment, the IEEE 1394 is used.
Although the bus has been described as an example, the method of the present invention can be applied to any bus other than the IEEE1394 as long as a similar network configuration can be realized.

[0042]

As described above in detail, according to the present invention, when a plurality of electronic devices are connected to a specific bus such as an IEEE 1394 bus to form a network, the electronic devices in the power saving state can be directly operated. In either case, by simply transmitting a command from another electronic device, power supply to each layer of the electronic device can be executed to switch to an operating state. As a result, it is possible to realize a network system that can always be used without any burden on the user.

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of a network system formed by an IEEE 1394 bus of the present invention.

FIG. 2 is a block diagram illustrating a configuration of an electronic device of the present invention.

FIG. 3 is an IE when the device is executing data transmission.
The figure which shows the flow of data in the protocol layer of EE1394.

FIG. 4 is a diagram showing a data flow when the own device mediates data transmission between other devices.

FIG. 5 is a flowchart showing an operation of a power supply control process in the electronic device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... CPU 2 ... System memory 3 ... Display controller 4 ... Power supply microcomputer 5 ... Power supply 6 ... Power supply control circuit 7 ... Link layer control circuit 8 ... Physical layer control circuit 9 ... Power button detection part 20 ... 1394 bus power supply management part 21 ... Application layer control unit 22 ... Middleware layer control unit 23 ... Transaction layer control unit 31 ... Display 81 ... Node ID holding unit 91 ... Power button 101 ... Application layer 102 ... Middleware layer 103 ... Transaction layer 104 ... Link layer 105 ... Physical layer

Claims (5)

[Claims] In a network system in which a plurality of electronic devices are connected to a specific bus to form a network, when an electronic device on the network is turned off, power is supplied only to a physical layer of the electronic device. A command is sent from the other electronic device to the electronic device in the power saving state via the specific bus, and a protocol layer including a physical layer of the electronic device in the power saving state is transmitted to the power saving state. A network system for executing power supply to all layers. 2. The network system according to claim 1, wherein said specific bus is an IEEE 1394 bus. 3. An electronic device having a data transmission function using a specific bus, wherein power supply to a protocol layer is independently controlled by a physical layer and other layers, and only when the power is turned off, only the physical layer is controlled. Power supply control means for supplying power to a power saving state; and obtaining a command from the outside via the specific bus when in a power saving state in which power is supplied only to the physical layer by the power supply control means. A command acquisition unit that determines whether or not the command acquired by the command acquisition unit is a command for itself, and if it is a command for itself, switches power supply to all layers of the protocol layer including the physical layer. An electronic apparatus, comprising: a control unit to be executed by the power supply control unit. 4. The electronic device according to claim 3, wherein the specific bus is an IEEE 1394 bus. 5. A power supply control method for an electronic device having a data transmission function using a specific bus, wherein power supply to a protocol layer is controlled independently by a physical layer and other layers, and when power is turned off. Power is supplied only to the physical layer to enter the power saving state, and in the power saving state where power is supplied only to the physical layer, an external command is acquired via the specific bus, and the acquired command is acquired. A power control method comprising: determining whether a command is a command for itself; and, if the command is for itself, supplying power to all layers of a protocol layer including a physical layer.