JPH0823584A - Electronic equipment control system - Google Patents

Abstract

PURPOSE:To perform the controls of the using band and the channels, etc., within a system even if connection information is not inquired from each equipment to a control equipment when the control equipment controlling the connection of the whole system exists. CONSTITUTION:A command processing part 21 transmits commands including the connection parameter registered in a CMT(connection management table) 3 to its own command processing execution part 22 when an AVM-(audio video manager) controlling the connection of the whole system does not exist within a communication system. The command processing execution part 22 executes an inter-equipment connection processing in accordace with this parameter. When the AVM exists, the command including the connection parameter registered in the CMT 3 is transmitted to the AVM and the inter-equipment connection processing is left to the AVM.

Description

Detailed Description of the Invention

[0001]

The present invention relates to digital data such as video data and audio data, for example IEEE-
Serial bus compliant with P1394 (hereinafter "P1394
Abbreviated as "serial bus". ) Related to transmission technology using a communication control bus.

[0002]

2. Description of the Related Art A system for connecting a plurality of electronic devices by a communication control bus capable of coexisting control signals and information signals, such as a P1394 serial bus, and communicating information signals and control signals between these devices is available. It is considered.

FIG. 14 shows an example of such a system.
This system includes four digital video tape recorders (hereinafter referred to as "VTRs"), one camcorder (hereinafter referred to as "CAMs"), one editing machine, and one computer. And P1 between each node
It is connected by a twisted pair cable of 394 serial bus. Since each device has a function of relaying information signals and control signals input from the twisted pair cable, this communication system is equivalent to a communication system in which each device is connected to a common P1394 serial bus.

When each device is connected to the P1394 serial bus to form a communication system, the bus is reset and I
The physical address (node ID) of each device is automatically determined by the method defined in EEE-P1394, and the cycle master and bus manager described later are also determined.

Data transmission in devices sharing a bus has a predetermined communication cycle (for example, 12) as shown in FIG.
Every 5 μsec) by time division multiplexing. The management of the communication cycle on the bus transmits a synchronization packet (cycle start packet: hereinafter referred to as "CSP"), which indicates that a predetermined device called a cycle master is at the start of the communication cycle, to another device on the bus. By doing so, data transmission in the communication cycle is started.

The form of data transmission during one communication cycle is as follows: Synchronous data such as video data and audio data (hereinafter referred to as "Iso data") and asynchronous data such as connection control commands (hereinafter referred to as "Async data"). There are two types. Then, the Iso data packet is transmitted before the Async data packet. Is
Channel number 1, 2, 3 for each data packet
, N can be distinguished from each other. After the transmission of Iso data packets of all channels to be transmitted is completed, the next CS
The period up to P is used for transmission of Async data packets.

A device that intends to send an Iso data packet to the bus first secures a channel and a band required for data transmission. Therefore, the channel and the required bandwidth are applied to a predetermined device (bus manager: hereinafter referred to as “BM”) that manages the channel and the bandwidth of the bus. As shown in FIG. 16, the BM includes a register REG1 indicating the usage status of each channel of the bus and a register REG2 indicating the remaining capacity of the bus. The node that intends to send out the Iso data packet sends a read command to these registers REG1 and REG2 using the Async data packet to read the contents of REG1 and REG2. If there is a free channel and free space, A
A write command is sent to the BM to write the channel and band that the user wants to use to the REG 1 and 2 using the sync data packet. If writing to the registers REG1 and REG2 succeeds, output to the bus becomes possible.

FIG. 17 shows the basic structure of a VTR which is a device in the communication system shown in FIG. This VTR is VT
In addition to the deck section 11 and the tuner section 12 which are the essential functional units as R, a digital interface to the P1394 serial bus (hereinafter referred to as "digital I / F").
Say. ) 13, this digital I / F 13 and deck unit 1
1 or a switch box unit 14 for switching connection of the tuner unit 12, and a communication control microcomputer 15. If the device is a CAM, there is a camera unit instead of the deck unit 11 and the tuner unit 12, and if it is an editing machine or a computer, there is a processing unit for video data and computer data.

In the device thus constructed, the communication control microcomputer 15 performs the inter-device connection. FIG. 18 shows a configuration for connecting the devices in the communication control microcomputer 15. The application 1 generates a command including parameters such as a communication partner and a band according to a setting operation of an operation unit (not shown) of the device by the user, and passes the command to the inter-device connection control unit 2. The inter-device connection control unit 2 uses these parameters as a table (Conn) for managing inter-device connection information.
section Management Table: Hereinafter referred to as “CMT”. ) 3, and performs inter-device connection processing such as acquisition of band and channel.

A bus reset occurs when the power of the device is turned off or when the device is inserted into or removed from the bus.
At this time, the communication control microcomputer 15 can maintain the inter-device connection before the reset by reestablishing the inter-device connection based on the inter-device connection information held in the CMT 3.

[0011]

In the communication system configured as described above, a device (Audio Video Mana) that manages connection between devices of the entire communication system.
ger: Hereinafter referred to as "AVM". ) Is provided to make efficient use of the bus by utilizing the transmission capacity of the entire bus, and to prioritize information signals to be output to the bus.

The AVM is a device such as a computer capable of managing the entire communication system. In order to become an AVM, A of all the devices in the system
It is necessary to write your own node ID in the VM register (not shown), and the device that succeeded in this writing is A
It becomes VM. Further, each device can determine whether or not there is an AVM in the system by checking whether or not the node ID is written in its own AVM register.

Some communication systems do not have an AVM. Further, before and after resetting the bus, presence / absence of AVM, change of AVM, etc. may occur.
Therefore, in order for the AVM to manage the device-to-device connection of the entire system, it is necessary for each device to inquire about the device-to-device connection information held in the CMT. Therefore, the number of communications required for inquiry increases in proportion to the number of devices connected to the system. Further, since there is a possibility that the connection between the devices is cut off and the band or the like is released without the AVM's knowledge, this is not limited to when the bus is reset,
It is necessary to inquire all devices of necessary information at fixed intervals or when necessary.

The present invention has been made in order to solve such a problem, and an object thereof is to provide an electronic equipment control system which eliminates the need for the AVM to inquire the equipment connection information to each equipment. To do.

It is another object of the present invention to provide an electronic device control system that simplifies the configuration of the portion that executes the inter-device connection processing and facilitates hardware implementation.

[0016]

In order to solve the above problems, an electronic device control system according to the present invention is a system for communicating information signals and control signals between a plurality of electronic devices connected by a bus, A management device for managing the connection of the entire system is provided in the system by providing a first means for selecting a destination of a control command for inter-device connection and a second means for executing the control command in each electronic device. If it exists,
The first means transmits the control command to the management device to perform the inter-device connection processing on behalf, and when the management device does not exist in the system, the first means transmits the control command to the second device. It is characterized by.

According to the invention, the second means is the first means.
It is layered below the means. The second means is preferably configured by hardware. Furthermore, according to the present invention, the first means is provided with a holding means for holding a parameter for inter-device connection. This holding means
Since the parameter of the inter-device connection is held until the control command for releasing the inter-device connection is executed, the inter-device connection can be maintained even at the bus reset.

According to the present invention, the second means is
It is configured to receive the control command fairly from itself and the first means in the other electronic device.

[0019]

According to the present invention, the first means transmits a control command for inter-device connection to the management device when there is a management device for managing the connection of the entire system, and when there is no management device, A control command for inter-device connection is transmitted to the second means. The management device or the second control means executes the received control command for inter-device connection.

[0020]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 shows a configuration for connecting devices in an embodiment of the present invention. The application 1 creates a command including parameters such as a communication partner and a band according to a user operation, and the command processing unit 21
Hand over to. The command processing unit 21 attaches a connection ID that is uniquely determined within the device to each connection, and registers it in the CMT 3 together with the parameters passed from the application 1. By passing this connection ID as a reply from the command processing unit 21 to the application 1, the application 1 thereafter only sends a command using the connection ID to uniquely determine the connection parameters.

If the AVM does not exist in the communication system, the command processing unit 21 sends a command including the connection parameter registered in the CMT 3 to its own command processing execution unit 22. The command processing execution 22 executes the inter-device connection processing according to this parameter. On the other hand, when the AVM exists, the command including the connection parameter registered in the CMT 3 is transmitted to the AVM and the inter-device connection processing is entrusted.

When the command processing unit 21 receives a disconnect command for disconnecting the connection between devices from the application 1, the command processing unit 21 determines whether an AVM exists in the communication system. As described above, this release command is a command using the connection ID. If the AVM does not exist, the release command is transmitted to its own inter-device connection processing unit 22, and if the AVM exists, the release command is transmitted to the AVM. The command processing unit 21 deletes the connection ID and the parameter from the CMT 3 after its own inter-device connection processing unit 22 or AVM performs the inter-device connection release process.

The application 1 and the command processing section 21 described above are composed of software. Also,
The command processing execution unit 22 may be configured by software or hardware, but it is desirable to realize cost reduction and processing speed increase by configuring it by hardware.

The parts for connecting the devices in each device have been described above, but the AVM basically has the same structure. However, the AVM is different in that it is configured to transmit and receive device-to-device connection information to and from each device.

The command processing execution unit 22 receives from the command processing unit 21 a request for connection between devices, etc., [1] connection (connect), [2] release (disconnectnec).
t), [3] protection (protect), and [4] unprotection (unprotect).

The command processing execution unit 22 executes possible processing according to the parameters of the inter-device connection request received from the command processing unit 21. Here, possible processing is
Refers to the processing held according to the capabilities of each device. For example, a computer capable of becoming an AVM is "AVM
When receiving the command "get off", if it is managed as an AVM, it is determined whether or not it is possible to get off the AVM. If it is not possible to get off the AVM or if it is not managed as an AVM, the AVM
Do not process to get off.

The inter-device connection processing will be described below. [1] Connection (1) Broadcast output For example, in the system shown in FIG. 14, when the CAM is set to the reproduction mode, the application 1 of the CAM sends a command for connection including the parameters of FIG. 2 to its command processing unit 21. Sent. The command processing unit 21 attaches a connection ID that is uniquely determined in the device to each connection, and the CMT together with the parameters passed from the application 1
Register to 3. If the AVM does not exist, the command of the connection including the parameters of FIG. 2 is passed to its own command processing execution unit 22. On the other hand, when the AVM exists, the connection command is passed to the command processing unit 21 of the AVM.

In FIG. 2, the parameter output node I
D is the ID of the device outputting the information signal (CA in this case)
Node ID of M). The output plug number is the number of the plug outputting the information signal (in this case, plug 0). The input node ID is the I of the device receiving the information signal.
It is D. In this case, the CAM is in the playback mode and outputs the information signal to the bus without specifying the input device.
It is a broadcast. The input plug number is the plug number that inputs the information signal. Here, since it is a broadcast output, it is “don't care”. BW (Bandwidth) is a band required for transmitting an information signal. PB (Protect Bi
t) indicates whether the inter-device connection is protected.
In this case, since it is 0, it is not protected. Connection ID = 1 is assigned to the inter-device connection having the above parameters.

Here, the plug in this embodiment will be briefly described. Since data packets are sent to the P1394 serial bus on time-divided channels, it is not necessary to separate signals for each channel by a physical plug. However, the result of determining the path from one device to another has the same meaning as connecting with an analog signal line.
Furthermore, when one device can handle a plurality of channels at the same time, it is necessary to distinguish them. Therefore,
In this embodiment, each device is provided with a virtual plug so that channels can be distinguished when inputting and outputting.

FIG. 3 shows an example of a virtual plug. Here, the virtual plug is the communication control microcomputer 1 of FIG.
It is a register provided in 5, and 4 bytes represent one plug. 4 bytes up to the address 00h-03h are input plug 0, and the following 04h-07h, 08h-0Bh,
0Ch-0Fh is used as the input plugs 1, 2, 3 and up to four are prepared. In addition, 4 bytes up to addresses 10h to 13h are output plugs 0, hereinafter 14h to 17h and 18
Output plugs 1, 2, and 3 are h-1Bh and 1Ch-1Fh, and up to four are prepared. Since it is sufficient to provide the input / output plugs by the number that the device can handle at one time, for example, for a device that can handle two input / output systems, the area "..." In the figure is an empty register. For both input and output, the plug 0 is used for input and output with respect to the default channel (fixed channel).

When the plug-enable of the input plug is set to 1, the digital I / F receives the Iso data packet from the channel set to the channel number. When the plug-enable of the input plug is cleared to 0, the digital I / F stops receiving. At that time, the other fields of the plug are also cleared to zero. Input plug PC (Pr
The Detect Counter) sets the LSB to 1 when protecting the signal connection with the transmitting device, and clears it to 0 when unprotecting.

When the plug-enable of the output plug is set to 1, the digital I / F uses the band indicated in Bandwidth for the channel set in the channel number at the transmission rate specified by DR (Data Rate). And transmits the Iso data packet. When the plug-enable of the output plug is cleared to 0, the digital I
/ F stops transmission. At that time, clear the other fields of the plug to zero. The PC of the output plug is increased by 1 when the signal connection with the receiving device is protected and is decreased by 1 when the signal connection with the receiving device is not protected, and the devices requesting protection are counted.

These plugs are used by the command processing execution unit 2
Prepared for 2. The connection control command is to write to these plugs. These plugs can be rewritten fairly by the transaction of P1394 without distinguishing themselves or from other devices. As a result, when a plurality of devices try to execute writing to the plug almost at the same time, they can be processed without contradiction. However, to protect the connection, P
Rewrite only when C is 0. Note that "---" in each plug is a reserved bit.

FIG. 4 shows the flow of broadcast output processing in the command processing section 21 when the CAM is set to the reproduction mode. First, in step S1, the band (BW:
Bandwidth) and default channel (DC
N: Default Channel Number)
If so, in step S2, the Iso data packet is output to the bus by using the plug 0 and the default channel, and the process ends.

If the band and the default channel cannot be obtained in step S1, the Iso data packet is input from the default channel in step S3, and the node I added to the header of the data packet is input.
Examine D. In other words, it checks the device that is outputting to the default channel.

Next, in step S4, the device whose node ID is checked in step S3 is instructed to stop the output, and if succeeded, in step S5, the released band and the band required by itself are set. If the adjustment is successful and this is successful, in step S2, the Iso data packet is output to the bus using the plug 0 and the default channel, and the processing ends.

If the output cannot be stopped in step S4 because the output of the default channel is protected or the like, the process is terminated. Step S
If the band cannot be adjusted in step 5, step S
At step 6, the band and the channel are released, and the process ends.

(2) Broadcast Input When the VTR 1 is digital-in or the like, it means broadcast input, as shown in FIG. 5, and the default channel is input. Therefore, at this time, CAM
Input the output of. The flow of the broadcast input process in this case is shown in FIG.

(3) One-to-one connection With the editing machine shown in FIG.
If TR3 is set to the recording mode, the connection parameters are as shown in FIG. In this way, specifying an input / output device and exchanging data between devices on a one-to-one basis is called a one-to-one connection.

The flow of the one-to-one connection processing in this case is shown in FIG. First, in step S1, the VTR 2 determines a band and an optional channel (OCN: Option Channel).
eNumber) is determined. Here, OCN indicates a channel number other than the default channel. If it has been acquired, the VTR 2 is instructed to output it, and then the VTR 3 is instructed to input it (steps S2 and S3), and the process ends. If it is determined in step S1 that the band and channel have not been acquired, the process ends.

Here, when the computer of FIG. 14 manages as the AVM, the connection command transmitted from the application 1 of the editing machine to the command processing unit 21 is passed to the command processing unit 21 of the computer. Then, from here, the command processing execution unit 22 of the computer
8 and the processing of FIG. 8 is performed based on the parameters of FIG.

[2] Release (1) Broadcast Output Stop FIG. 9 shows the flow of processing when the CAM is set to the stop mode and the broadcast output is stopped. Step S1
Is a process of stopping the output, and step S2 is a process of releasing the band and the channel. As described above, the stop of the input is executed by setting the plug-enable of the output plug 0 of the CAM to 0. The release of the band and the channel is executed by sending a write command for releasing the band and the default channel number to REG1 and REG2 of the BM.

(2) Stop of Broadcast Input FIG. 10 shows the flow of processing when the VTR 1 is set in the stop mode and the broadcast input is stopped.

(3) One-to-one connection interruption FIG. 11 shows the flow of processing when the work between VTR2 and VTR3 in the editing machine is stopped. Step S1 is VT
This is a process of determining whether or not R2 has stopped output. If the output is stopped, the VTR 2 is instructed to release the band and the channel, and then the VTR 3 is instructed to stop the input (steps S2 and S3). AVM
The transition of the command depending on the presence or absence of is similar to that at the time of one-to-one connection.

[3] Protect (1) Broadcast Output / Input In the case of broadcast output and input, a protect command may occur during recording or the like. For example, CAM
Input the output of VTR1 with VTR, and if recording, VT
R1 sets the PC of its own input plug 0 to 1 and increases the PC of its CAM output plug 0 by 1. The processing flow in this case is shown in FIG.

(2) One-to-one connection In the one-to-one connection, at the same time as the connection processing is performed, the protection is automatically set to protect the connection between the devices. In other words, the output device is the output plug PC 1
In the case of increasing and inputting the device, the processing of setting the PC of the input plug to 1 is automatically performed. Therefore, no protection command is issued.

[4] Unprotect (1) Broadcast output / input For example, when a request for removing the protection of [3] (1) is received, the PC of the output plug 0 of the CAM is decremented by 1, and Set the PC of input plug 0 to 0. FIG. 13 shows the flow of processing for canceling the protection in this case.

(2) One-to-one connection In the one-to-one connection, protection is provided to protect the connection between the devices at the same time as the connection processing is performed. Then, with the release of the one-to-one connection, the connection protection is released.
In other words, the output device automatically reduces the output plug PC by 1, and the input device automatically sets the input plug PC to 0. Therefore, unprotected commands do not occur.

As described above, in the present embodiment, the inter-device connection control is divided into the command processing section 21 and the command processing execution section 22, and the processing of the command processing execution section 22 is simplified. 22 can also be made into hardware.

[0050]

As described in detail above, according to the present invention, when a management device for managing the connection of the entire system exists, a command is sent to the management device, and when it does not exist, a command is sent to its own command processing execution unit. Send. Therefore, when there is a managed device, it is possible to manage the used band and channel in the system without inquiring each device of the managed device about the connection information.

Also, by dividing the command processing unit and the command processing execution unit into layers, the processing of the command processing execution unit can be simplified, so that the command processing execution unit can be easily made into hardware, and the cost can be reduced. It is possible to realize higher efficiency and higher processing speed.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration for connecting devices according to an embodiment of the present invention.

FIG. 2 is a diagram showing the contents of a CMT included in a CAM.

FIG. 3 is a diagram showing an example of a plug.

FIG. 4 is a diagram showing a flow of broadcast output processing in a command processing unit.

FIG. 5 is a diagram showing the contents of CMT possessed by the VTR 1.

FIG. 6 is a diagram showing a flow of broadcast input processing in a command processing unit.

FIG. 7 is a diagram showing the contents of CMT possessed by the editing machine.

FIG. 8 is a diagram showing a flow of one-to-one connection processing in a command processing unit.

FIG. 9 is a diagram showing a flow of broadcast output stop processing in a command processing unit.

FIG. 10 is a diagram showing a flow of broadcast input stop processing in a command processing unit.

FIG. 11 is a diagram showing a flow of one-to-one connection release processing in a command processing unit.

FIG. 12 is a diagram showing a flow of protection processing in a command processing unit.

FIG. 13 is a diagram illustrating a flow of non-protection processing in a command processing unit.

FIG. 14 is a diagram showing an example of a communication system using a P1394 serial bus.

FIG. 15 is a diagram showing an example of a data structure on a bus in a communication system using a communication system using a P1394 serial bus.

FIG. 16 is a diagram illustrating a method of securing channels and bands in a communication system using a P1394 serial bus.

17 is a diagram showing a basic configuration of a VTR in the communication system of FIG.

18 is a diagram showing a configuration for a communication control microcomputer in the VTR of FIG. 14 to perform interdevice connection.

[Explanation of symbols]

1 ... Application, 21 ... Command processing unit, 22 ...
Command processing execution unit, 3 ... CMT

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Makoto Sato 6-735 Kitashinagawa, Shinagawa-ku, Tokyo Sony Corporation

Claims (4)

[Claims] 1. In a system for communicating information signals and control signals between a plurality of electronic devices connected by a bus, first means for selecting a destination of a control command for device-to-device connection in each electronic device. , A second means for executing the control command is provided, and when there is a management device for managing the connection of the entire system in the system, the first means sends the control command to the management device. An electronic device, wherein the first device transmits the control command to the second device when the management device does not exist in the system by transmitting the device connection processing on behalf of the device. control method. 2. The electronic device control system according to claim 1, wherein the second means is layered below the first means. 3. The electronic equipment control system according to claim 1, wherein the first means has a holding means for holding a parameter for inter-device connection. 4. The electronic device control system according to claim 1, wherein the second means fairly receives the control command from itself and the first means in other electronic devices.