JP2001285314A - Device status notification method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To resolve the problem that the frequency of the bus usage is increased for a device (controller) connected to an IEEE1394 serial buss to obtain a status of other device (target) because at first a AV/C Status command or a AV/C Notify command must be transmitted from a controller to other device (target). SOLUTION: In this method, informing positively the status of own device to other device so as to reduce using frequency of serial bus.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a status notification device and a status notification method. The present invention relates to a status notifying device and a status notifying method for notifying the status information.

[0002]

2. Description of the Related Art A conventional technique will be described below with reference to FIGS.

Conventionally, when a plurality of devices connected via an IEEE1394 serial bus are used to control other devices or acquire information of other devices, commands (hereinafter referred to as AV / C standards) defined by the AV / C standard are used. AV / C command) was used. In particular, when acquiring information on other devices, among AV / C commands, Status command (hereinafter referred to as AV / C Status command),
And the Notify command (hereinafter, the AV / C Notify command) was used.

When the AV / C Status command is used as shown in FIG. 8, the following method has been used. That is, the device 11 (hereinafter, a controller) that performs an operation of acquiring information transmits an AV / C Status command to the device 12 (hereinafter, a target) that provides information. The target receives the AV / C Status command from the controller, creates an AV / C Status response storing current status information to be notified to the controller specified by the command, and transmits the AV / C Status response to the controller. Thus, AV
By using the / C Status command, the controller was able to obtain the current status information of the target.

However, in the case of using the AV / C Status command, in order for the controller to acquire the target state change without delay, the controller must use the AV / C Status command.
The tus command must be transmitted continuously, for example, periodically, and the occupancy of the IEEE1394 serial bus becomes high.

On the other hand, when the AV / C Notify command is used as shown in FIG. 9, the following method has been performed. The controller 11 sends the AV / C
Send Notify command. The target 12 receives the AV / C Notify command from the controller 11, creates an AV / C Interim response storing the current status information to be notified to the controller 11 specified by the command, and transmits the response to the controller 11. I do. The target 12 monitors the status information specified by the AV / C Notify command, and when the status changes, creates an AV / CChanged response storing the status information after the change, and transmits the response to the controller 11.

As described above, by using the AV / C Notify command, the controller 11
Can be obtained, and when the state information changes, the changed state state information can be obtained immediately.

However, when the controller 11
AV / C when the status of 2 must be monitored continuously
After an AV / C Changed response to the Notify command is returned from the target 12, the AV / C Notif
There was a problem that a y command had to be sent.

When the target 12 receives the AV / C Notify command, it must store the controller information of the reply destination in the storage area of the target 12 until the target 12 transmits the Changed response to the controller 11. . For this reason, a plurality of AV
There is a problem that the size of the storage area must be increased in consideration of the case where the / C Notify command is sent.

[0010]

Conventionally, in order for a device (controller) connected to the IEEE1394 serial bus to acquire the status of another device (target), the controller first sends an AV / C Status command to the target. Or they had to send an AV / C Notify command.

Further, in order to quickly acquire the state of the target, the above command must be continuously transmitted from the controller. For this reason, there has been a problem that the use frequency of the bus increases.

When the AV / C Notify command is used, the device (target) receiving the AV / C Notify command needs to store the transmission source device (controller), and the device must be connected to the serial bus. As the number of connected devices increases, there is a problem that a large storage area for the target must be secured.

[0013]

A state notification method according to the present invention is a method for notifying a state of a first device connected to a plurality of devices on a home network, wherein the first device is provided in the first device. And state information detecting means for notifying the at least one of the plurality of devices connected by the home network of the detected state information of the first device.

[0014] A status notification device according to the present invention includes: a first device connected to a plurality of devices on a home network;
State information detection means provided in the first device for detecting state information of the first device; and the state information of the first device obtained by the state information detection means being connected to the home device by the home network. Notification means for notifying at least one of the plurality of devices.

With this configuration, the present invention can reduce the frequency of use of the serial bus by actively notifying the status of the own device to other devices. Further, it is possible to promptly notify other devices of the status information. In addition, as other devices to be notified, devices that have a connection established by CMP specified in IEC61883-1, all devices existing on the IEEE1394 serial bus, or devices that are set in advance can be used. Status information can be notified to devices that need the information.

[0016]

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

First, a first embodiment will be described. FIG. 1 shows a DTV (digital TV) 1 and a DVHS (digital V
HS) 2, STB (set top box) 3 is IEEE1
394 is a home network connected by the serial bus 4. In FIG. 1, the MPEG2 stream reproduced by the DVHS2 is transferred from the DVHS2 to the DTV1 by using the isochronous data transfer of the IEEE1394 serial bus 4, and is displayed on the DTV1 screen.

Here, for example, when the DVHS2 tape has advanced to the end, the DVHS2 sends an error message to the DT using the AV / C Vendor Control command 5.
V1 and STB3 (FIG. 2).

In this embodiment, the destination of the message is
All nodes are connected to the IEEE1394 serial bus 4. In other words, although not specifically shown, for example, IEEE13
94 The number of devices connected to the serial bus 4 is DTV, D
If the TV, STB and DVHS are four, DVH
S sends an AV / C Vendor Control command indicating an error message to all devices on the IEEE1394 serial bus 4 except for the two DTVs and one STB.

By notifying the state information such as the DVHS 2 having entered an error state to all the nodes on the IEEE1394 serial bus 4 using the AV / C Vendor Control command 5, the nodes on the serial bus 4 Status information of other devices can be immediately recognized. Also, AV / C
It is possible to reduce an increase in the frequency of use of the bus that occurs when using the Notify command or the AV / C Status command.

Next, a second embodiment will be described. The home network takes the same form as in the first embodiment.
In FIG. 3, reference numeral 6 indicates that a connection is established based on the CMP defined in IEC 61883-1. For example, when the DVHS 2 is in an error state, the device for which the connection shown in 6 of FIG.
An error message is sent to only 1 using the AV / C Vendor Control command.

Next, an example of means for finding a device that has established a connection will be described. For example, AV / C Vendor Contro
The oPCR is set so that a node that transmits an error message using the l command, in this embodiment, the DVHS 2 outputs to the serial bus 4.

When the oPCR is set, the DVHS2 sets the IEEE13
94 Read the iPCR values of all devices connected to the serial bus 4 and read the channel n
Find a device that has an iPCR set to the same value as the umber area. Then, an AV / C Vendor Control command is transmitted to the device found by the above procedure.

Similarly, when the iPCR is set so that the DVHS 2 receives the data stream from the serial bus, the oPCR of all the other devices is read and the channel numb is read.
By comparing the er areas, it is possible to find other devices that have established a connection with the DVHS2.

In the process of establishing a connection, a node instructing to establish a connection
(Hereinafter referred to as a controller) and a node (hereinafter referred to as a target) instructed to establish a connection.

In this embodiment, the AV / C Vendor Control
The destination to send the l command may be only the controller node or only the target node. Further, both the controller and the target may be used.

For example, as shown in FIG. 4, the controller may be a node that has established connection 6. In FIG. 4, an arrow 7 indicates transmission of a control command for establishing a connection.

As shown in FIG. 4, when the controller has established a connection, the AV / C to be transmitted when the DVHS 2 enters an error state as in the first embodiment.
The destination of the Vendor Control command can be found by reading and comparing the iPCR and oPCR of the node on the serial bus 4.

In some cases, as shown in FIG. 5, an instruction is issued to establish a connection between other devices. FIG.
TV1 connects to DVHS2 and STB3
Is an example of transmitting a control command to establish In FIG. 5, arrow lines 8 and 9 indicate connection 6
Represents the transmission of a control command for establishing

FIG. 5 shows an example in which a controller node is found when the node that establishes connection 6 is different from the controller. The target, for example, DVHS2 in FIG. 5, receives the control command 8 for establishing the connection 6 transmitted from the DTV1.

The DVHS 2 stores the device that has transmitted the control command 8, in this embodiment, the DTV 1. Here, when the DVHS2 falls into an error state as in the first embodiment, the destination is the DTV1 destination stored in the above-described method, and the AV / C Vendor is transmitted to the controller.
Control commands can be sent.

As in this embodiment, the AV / C Vender Control
l By sending the command to the node that established the connection, or to the controller or target at the time of establishing the connection, it is possible to send or receive the data stream with devices that may send and receive the data stream. By using the AV / C Vendor Control command to notify the status information such as the error status only to the device that performs the error, nodes on the serial bus can immediately recognize the status information of other devices .
Further, it is possible to reduce the frequency of use of the bus that occurs when using the AV / C Notify command or the AV / C Status command.

Next, a third embodiment will be described. FIG.
Is a schematic diagram of this embodiment. Connection 6 between DTV 1 and DVHS 2 connected to 1394 serial bus 4
Has been established. In addition, the DTV1 and the DVHS
Between 2, the transmission and reception of the Isochronous Data Stream 10 is performed.

For example, the destination of the AV / C Vendor Control command transmitted when the DVHS 2 enters an error state is another device that transmits and receives the Isochronous Data Stream 10. In this embodiment shown in FIG. 6, an AV / C Vendor Control command indicating an error state is transmitted to the DTV 1.

As in this embodiment, AV / C Vender Control
Using the AV / C Vendor Control command to notify status information such as an error status only to the device that is transmitting and receiving the IsochronousData Stream as the command transmission destination, the node on the serial bus allows other devices Can be immediately recognized. Also, AV / C
It is possible to reduce the frequency of use of the bus that occurs when using the Notify command or the AV / C Status command.

Next, a fourth embodiment will be described. FIG.
Is a schematic diagram of this embodiment. FIG. 7 shows DTV1 and DV.
HS2 and STB3 are home networks connected by an IEEE1394 serial bus 4. In FIG. 7, the DTV
1 and DVHS2 are made by A company, and STB3 is made by B company.

Here, for example, it is assumed that the DVHS 2 is set in advance as a product of company A as a destination to which status information is transmitted when an error occurs. For example, DVHS2 sends an error message to AV / C Vendo
Send to DTV1 using rControl command. As a means for identifying the manufacturer shown in this embodiment, ConfigRO
The GUID described in M can also be used.

In this embodiment, a node on the serial bus is notified by using the AV / C Vendor Control command to notify a node of a preset type of status information such as an error state of the DVHS 2 or the like. Status information of other devices can be immediately recognized. Also,
It is possible to reduce an increase in the frequency of use of the bus that occurs when using the AV / C Notify command or the AV / C Status command.

[0039]

According to the present invention, the frequency of use of the serial bus is reduced by actively notifying the status of the own device to other devices between the devices connected by the IEEE1394 serial bus, thereby reducing the frequency of use of the serial bus. Communication burden can be reduced. Further, the other device can acquire the state information immediately when the state change occurs. Other devices to be notified may be devices that have a connection established by CMP defined by IEC 61883-1, devices that perform an operation to establish a connection, devices that perform isochronous data transfer, IEEE1394 By using all devices existing on the serial bus or using devices that are set in advance, status information can be transmitted to devices that require device status.

[Brief description of the drawings]

FIG. 1 is a schematic diagram of a home network according to the present invention.

FIG. 2 is a diagram showing an example in which status information is notified to all devices according to the present invention.

FIG. 3 is a schematic diagram when a connection according to the present invention is established.

FIG. 4 is a diagram showing a first example showing connection establishment and control at that time.

FIG. 5 is a diagram showing a second example of connection establishment and control at that time.

FIG. 6 is a diagram showing connection establishment and isochronous data transmission.

FIG. 7 is a diagram showing an example in which status information is notified to a device designated in advance.

FIG. 8 is a diagram showing an example of a conventional home network.

FIG. 9 is a diagram showing another example of a conventional home network.

[Explanation of symbols]

 1 ... DTV 2 ... DVHS 3 ... STB 4 ... IEEE1394 serial bus 5 ... AV / C Vendor Control command 6 ... Connection 7 ... Connection establishment control instruction 8 ... Connection establishment control instruction 9 ... Connection establishment control instruction 10 ... Isochronous data stream

Claims (12)

[Claims] 1. A method for notifying a status of a first device connected to a plurality of devices on a home network, said status information detecting means being provided in the first device and detecting status information of the first device; Notifying means for notifying the detected state information of the first device to at least one of the plurality of devices connected via the home network. 2. A method for notifying the status of a first device connected to a plurality of devices on a home network using an IEEE1394 serial bus, wherein status information of the first device provided in the first device is detected. A status notification method comprising: status information detection means; and notification means for notifying at least one of the plurality of devices connected by the home network of the detected status information of the first device. . 3. The detected status information of the first device is:
The status notification method according to claim 1, wherein the notification is made to at least one of the plurality of devices in which a predetermined connection has been established with the first device. 4. The detected status information of the first device is:
The status notification method according to claim 1, wherein the notification is provided to at least one of the plurality of devices performing the isochronous data transfer with the first device. 5. The state information of the detected first device is:
The state according to claim 1, wherein the second device having a predetermined connection established between the first device and at least one of the plurality of devices is notified. Notification method. 6. The status notification method according to claim 1, wherein the detected status information of the first device is notified to all the plurality of devices connected to the home network. . 7. A first device connected to a plurality of devices on a home network, status information detection means provided in the first device for detecting status information of the first device, and the status information detection Notification means provided in the first device for notifying the state information of the first device obtained by the means to at least one of the plurality of devices connected by the home network. Status notification device to be. 8. A first device connected to a plurality of devices on a home network using an IEEE1394 serial bus, and status information detecting means for detecting status information of the first device provided in the first device. And a notifying unit for notifying the detected state information of the first device to at least one of the plurality of devices connected via the home network. 9. The detected state information of the first device includes:
9. The status notification device according to claim 7, wherein a notification is sent to at least one of the plurality of devices in which a predetermined connection is established with the first device. 10. 10. The detected state information of the first device is notified to at least one of the plurality of devices performing isochronous data transfer with the first device. The status notification device according to claim 7 or 8, wherein: 11. The apparatus according to claim 7, wherein the status information of the first device obtained by the status information detecting means is notified to all of the plurality of devices connected by the home network. The status notification device described in. 12. The detected state information of the first device includes a second device in which a predetermined connection is established between the first device and at least one of the plurality of devices.
The status notification method according to claim 7, wherein the status notification method is notified to a device.