JPH04347950A - Bus system - Google Patents

Abstract

PURPOSE:To effectively operate a bus system by preventing the occurrence of an abnormality at the time of the communication with the removed terminal caused by the remaining of each terminal information registered in a master terminal also after the slave terminals are removed from the bus system, regarding the bus system performing the communication between terminals via a bus. CONSTITUTION:In the bus system provided with a bus system communication route 1, more than a slave terminal 2 and a main terminal 3 storing the information of the slave terminal 2 and controlling the communication route 1, a reregistering requesting means 4 operating by the manual operation is provided on at least one more of the main terminal 3 and the slave terminal 2. The main terminal 3 restores the information of the terminal 2 in accordance with the operation of the reregistering requesting means 4.

Description

[Detailed description of the invention]

0001

[Industrial Field of Application] The present invention relates to a bus system in which a large number of terminals are connected and can exchange data with each other, and is designed to prevent abnormalities caused by the absence of a terminal due to removal of the terminal, for example. Regarding home bath systems for home use.

0002

2. Description of the Related Art In order to perform data communication between a large number of terminals, there is a communication system that connects each terminal to a bus-type communication path. For example, it is a network called LAN. This includes home bus systems for communication systems in the home, including EIAJ's ET-21
The standard is set as 01.

FIG. 5 shows an example of the configuration of the above-mentioned bus system.
Shown below. 1c is a bus-type communication path (hereinafter referred to as the bus), and this bus 1c has a main terminal (hereinafter referred to as the master terminal) and a slave terminal (hereinafter referred to as the slave terminal).
are connected to each other, and these terminals communicate with each other via bus 1c to exchange data. Since a large number of terminals are connected to the bus 1c, the master terminal 3c performs control to manage the bus 1c to prevent data collisions from occurring on the bus 1c.

[0004] The master terminal 3c connects any slave terminal 2c to the bus 1c in order to control the bus 1c described above.
It is necessary to remember whether it is connected. For example, in a home bus system, the stored information includes the type of slave terminal, whether an information channel is used, whether a telephone line is used, and the like. In addition, in the home bus system, slave terminals are divided into four groups according to their types, and addresses are assigned to each group.

[0005] In any case, the master terminal 3c needs to store information regarding the slave terminal 2c, and performs operations to detect connected slave terminals and store related information. This is called device registration. In conventional bus systems, terminals are registered not only when starting up the bus system, that is, when starting up the master terminal 3c, but also when starting up after connecting a new slave terminal 2c and turning on the power, and when starting up the master terminal 3c. This is when the terminal detects an abnormality in the bus system.

FIG. 6 shows a terminal registration sequence when starting up the bus system in the home bus system. As shown in the figure, after a certain period of time has elapsed since power has been turned on to the bus system including the master terminal 3c, when all the terminals have become operational, the master terminal 3c sends a registration start signal onto the bus 1c. This signal is sent for each address group determined according to the type of connected terminal. Slave terminal 2c detects this registration start signal and sends a registration request signal containing information regarding slave terminal 2c onto bus 1c. The master terminal 3c receives this, stores the information regarding the slave terminal 2c, and then sends a registration confirmation signal containing the same information as the stored information to the bus 1.
c Send up. The slave terminal 2c receives this and confirms that it matches the sent information, completing the registration for this slave terminal 2c.

The above series of registration operations is performed for slave terminals belonging to the same address group, and then also for slave terminals in other address groups, and the terminal registration operation is completed. The operation when the slave terminal 2c is connected and started after the bus system is started is shown in FIG. In this case, a registration request signal is sent onto the bus 1c from the newly started slave terminal 2c, and the registration operation is performed only for this slave terminal.

When the master terminal 3c detects an abnormality in the bus system, it sends a system reset signal requesting initialization to the slave terminal 2c, and after a certain period of time has elapsed, performs the same operation as when starting the system. and re-register all connected slave terminals 2c.

[0009]

In conventional bus systems, after the bus system is started up, terminal re-registration of the entire system is only required when an abnormality is detected in the bus system. Therefore, even if the slave terminal 2c is removed from the bus system, the removed slave terminal 2c is registered as existing in the master terminal 3c, and the registration cannot be deleted.

[0010] Therefore, the slave terminal 2c was removed.
If communication is performed, communication will not be possible and a bus system error will occur. In such a case, if communication is not possible after several attempts, the bus system will become abnormal, and the slave terminal 2c will be re-registered after the system is reset. When the slave terminal 2c 2 is removed from the bus system in this way, it becomes clear that the slave terminal 2c 2 does not exist until communication is performed with the removed slave terminal 2c 2 . Communication occurs when the slave terminal 2c is about to be used, and it is extremely important from the point of view of effective use of the bus system that a system abnormality occurs when such a bus system operation is required. This is a problem.

[0011] Furthermore, as mentioned above, the time required for the operation to determine that there is an abnormality in the bus system and for the re-registration operation may take a considerable amount of time, such as when an external communication line is used. This becomes a particularly big problem. The present invention has been made in view of the above problems, and when a slave terminal is removed from a bus system, it is discovered that the removed slave terminal does not exist until communication is performed with the removed slave terminal. The aim is to improve the inefficiencies of the current bus system.

0012

[Means for Solving the Problems] In order to solve the above-mentioned problems, the bus system of the present invention provides a manual switch that, when a slave terminal is removed from the bus system, notifies the slave terminal of the removal and causes the terminal to be re-registered. will be established. One or more manual switches may be provided in slave terminals other than the removed slave terminal or in the master terminal. FIG. 1 is a diagram showing the basic configuration of a bus system according to the present invention. In addition, parts having similar functions, including other figures, are designated by the same numbers, and parts other than those shown in FIG. 1 are designated by lowercase letters.

That is, the bus system of the present invention includes a bus-type communication path 1, one or more slave terminals 2 connected to the communication route 1, and controls the communication route 1 by storing information regarding the slave terminals 2. Main terminal 3 connected to communication path 1 as shown in
A bus system comprising a reregistration requesting means 4 operated by manual operation provided in at least one of the main terminal 3 and the slave terminal 2, and in response to the operation of the reregistration requesting means 4, the main terminal The terminal 3 is a bus system characterized by re-storing information regarding the slave terminal 2.

[0014]

[Operation] When the main terminal (master terminal) 3 starts up the bus system, it registers information regarding the slave terminal (slave terminal) 2 connected to the bus-type communication path 1. When a slave terminal 2 is newly connected to the communication path 1 and the power is turned on, only the newly connected slave terminal 2 is registered as before.

[0015] When the connected slave terminal 2 is removed from the communication path 1, the re-registration request means 4 in the main terminal 3 or another slave terminal 2 is activated by manual operation. When the re-registration request means 4 in the main terminal 3 operates, the main terminal 3 detects this, performs an appropriate evacuation operation, and then registers the connected slave terminal 2 as it is. Since this registration registers the slave terminal 2 connected to the communication path 1 at that time, the detached slave terminal 2 is deleted from the registration. In addition, when the re-registration request means 4 in another slave terminal 2 is operated, the slave terminal 2 having the re-registration request means 4 responds to this by sending a signal on the communication path 1 requesting a re-registration operation. The main terminal 3 detects this signal and performs the re-registration operation in the same manner as above.

In any case, re-registration is performed in response to the operation of the re-registration requesting means 4, and the removed slave terminal 2 is deleted from the registration, so it is not possible to communicate with a slave terminal 2 that does not exist in the bus system. The resulting abnormality will not occur, and efficient use of the bus system will be possible.

[0017]

[Embodiment] An embodiment in which the present invention is applied to a home bus system specified by the above-mentioned EIAJ, ET-2101 will be described. FIG. 2 shows the configuration of this embodiment. 1a is a bus using a coaxial cable. Reference numeral 3a is a master terminal for controlling this bus system, and the inside thereof is composed of an interface for connecting a control microcomputer system and bus 1a. 21a to 23a
is a slave terminal, 21a is an AV device, and 22
a is a heating and cooling device, and 23a is a facsimile.

In this embodiment, switches 4a, 41a, and 43a are used to cause the master terminal 3a, AV equipment terminal 21a, and facsimile 23a to re-register the terminals.
is installed. Processing for communication including the master terminal 3a and slave terminals 21a, 22a, and 23a is performed by a microcomputer system, and an example of the configuration of the communication system portion for this purpose is shown in FIG. In Figure 3, 1b is a home bus, 5b is a microcomputer, 6b is a ROM, and 7b is an RA
It is M. 10b is a communication port for communicating with the home bus. In the case of a master terminal, the above configuration is the basic configuration, and in the case of a slave terminal, a terminal device 9b is connected to the above configuration via an I/O port 8b. Further, in this embodiment, the manual switch 4b
This is connected to the interrupt signal terminal of the microcomputer 5b.

In the configuration of FIG. 3, a microcomputer system for home bus communication is added to the connected device 9b, but the microcomputer system of the connected device 9b may also perform the function of the microcomputer system for communication. Also, the master terminal may be a personal computer or the like without using a dedicated microcomputer system.

FIG. 4 shows the operation for re-registration when the communication microcomputer system shown in FIG. 3 is used as a master terminal. First, press the re-registration request switch 4b. In response to this, an interrupt to the microcomputer 5b occurs in step 101. In step 102, the evacuation operation is performed in response to the interrupt, and after the evacuation operation is completed, step 1
03 via the communication port 10b, the home bus 1b
A registration start signal is output to the top. The remaining slave terminals that have received the registration start signal and are directly connected to the home bus 1b output a registration request signal onto the home bus 1b. In step 104, the signal output on the home bus is read, and in step 105 it is determined whether it is a registration request signal. If it is a registration request signal, the terminal is registered in step 106, and a registration confirmation signal is output in step 107, thereby completing the registration operation for one slave terminal.

Steps 104 to 107 are repeated as many times as there are connected slave terminals, and the process is complete when all slave terminals are registered. Actually, steps from step 103 are repeated for each address group, but the explanation is omitted here. The above explanation shows the case where the re-registration request switch on the master terminal is operated, but when the re-registration request switch on the slave terminal is operated, this causes an interrupt to the slave terminal's microcomputer. In response to this, a signal indicating that there is a re-registration request is output on the home bus. Then, the master terminal detects this signal and performs step 102 in FIG.
The following operations are performed.

In the flowchart of FIG. 4, the re-registration operation is performed within an appropriate time in response to an interruption by the re-registration request switch. However, whether this re-registration operation should be performed with priority over other operations differs depending on the bus system. Therefore, when the bus system is operating at a high density (hereinafter referred to as busy), priority is given to operations that are already in progress or urgent operations, and re-registration operations are performed when the bus system is no longer busy. This makes more efficient use of the bus system.

[0023] When a slave terminal is removed from the bus system, re-registration cannot be requested even if the removed slave terminal has a re-registration request switch. Therefore, the re-registration request switch attached to the master terminal and other slave terminals is activated. Therefore, it is desirable to have a re-registration switch near the removed slave terminal, so it is desirable that the master terminal and the slave terminal each have a re-registration request switch, so that a re-registration request can be made from the nearest terminal.

[0024]

[Effects of the Invention] According to the present invention, conventionally, when a terminal is removed from the bus system, the registration of the terminal is maintained as it is. It was abnormal, but
According to the present invention, it is possible to always know the correct terminal status and to operate the bus system efficiently.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the basic configuration of a bus system according to the present invention.

FIG. 2 is a diagram showing the configuration of an embodiment in which the present invention is applied to a home bus system.

FIG. 3 is an example in which the communication system portion of each terminal including a master terminal and slave terminals is configured with a microcomputer.

FIG. 4 is a flowchart showing a re-registration operation when the microcomputer system of FIG. 3 is used as a main terminal.

FIG. 5 is a configuration example of a conventional bus system.

FIG. 6 is a diagram showing a sequence of terminal registration at system start-up in the home bus system.

FIG. 7 is a diagram showing a sequence when only one terminal is further started up after the system is started up in the home bus system.

[Explanation of symbols]

1...Bus type communication route 2...Slave terminal (slave terminal) 3...Main terminal (master terminal) 4... Re-registration request means

Claims (1)

[Claims] Claim 1: A bus-type communication path (1) and one or more slave terminals (2) connected to the communication path (1).
and a main terminal (3) connected to the communication path (1) so as to store information about the slave terminal (2) and control the communication path (1). A reregistration requesting means (4) operated by manual operation is provided in at least one of the main terminal (3) and the slave terminal (2), and the reregistration requesting means (4) is operated by manual operation.
4) Depending on the operation of the master terminal (3), the slave terminal (3)
2) A bus system characterized by re-memorizing information regarding.