JP2593456B2 - Address management method in CATV system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a CATV system in which one or more specific terminal devices are inquired to perform so-called selecting addressing for prompting data reception. The present invention relates to a device address management method.

[Conventional technology]

As a feature of the broadcasting service using the CATV system, there is a viewing permission function or a viewing request function for each group using an addressable controlled device. In this transmission system, for example, as shown in FIG. 1, a central control device 1 and a terminal device 5 are connected by a relay line 4 via a relay amplifier 2 and a tap-off 3. Conventionally, the selecting addressing for realizing this service is based on a redundant address unique to the controlled device 6 which is fixed by a dip switch or a fuse and cannot be easily changed when the controlled device 6 such as a terminal device is installed. Is being done.
At the time of designing the system, the maximum number of controlled devices 6 connected to the entire system is determined, and the maximum address quantity is allocated in advance to each route, district, group, or the like. During system operation, selecting and addressing is performed using the fixed address unique to the controlled device 6, and information communication with each controlled device 6 is performed.

[Problems to be solved by the invention]

However, in the above conventional method, the controlled device 6
Addresses are pre-allocated and fixed for each route, district, group, etc., and therefore cannot be expanded so as to exceed the maximum address quantity in each section. It is difficult to deal with connection changes and the like. If the maximum address quantity is given a margin at the time of system design in order to avoid this drawback, the efficiency of selecting addressing is reduced. In addition, since control other than the control of the controlled device 6 by the division determined at the time of system design cannot be performed, the above-described operation is performed for each route, each district, each group, and the like. There is a problem that it is not possible to easily change the system according to the service contents (purpose), such as information on a cleaning duty and a children's association, and information on a hobby club.

[Means for solving the problem]

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and comprises a central control unit, a controlled device such as a terminal device, and a relay line connecting the central control unit and a controlled device designated by address information transmitted from the central control device. In a CATV system in which the control device operates under the control of the central control device, every time the system is started up, selecting addressing is performed using an address unique to the controlled device, and the service content of the system separately from the address unique to the terminal device (purpose). Alternatively, a plurality of addresses where duplicates exist among a plurality of controlled devices organized according to the scale are stored in the controlled device, and the controlled device can be selected based on the stored address during system operation. Things.

According to the present invention, the logical address is stored every time the system is started. Therefore, when a new terminal device is to be connected, the operation is stopped and the system is restarted.

The CATV system is a tree-like network composed of a plurality of controlled devices 6 such as terminal devices 5 for one central control device 1 as shown in FIG. 1, and the central control device 1 selects and controls a specific controlled device. To do this, each controlled device 6 needs a unique address. The unique address of the controlled device 6 is set in a structure that cannot be easily changed such as a dip switch or a fuse when the controlled device 6 is installed, and is registered and managed in the central control device 1. Every time the system is started, the selecting addressing is performed by the unique address of the controlled device 1, and the overlapping between a plurality of controlled devices, which is organized in advance according to the service contents (purpose) or scale of the system, is performed. A plurality of existing addresses are stored in a memory in the controlled device 6 where reading and writing can be easily performed.

The selecting addressing at the time of operating the system is performed by the address stored in the controlled device 6 every time the system is started.

The first table is an address list corresponding to a unique address of the controlled device 6 every time the system is started, and this address is stored in a memory in the controlled device 6 where reading and writing can be easily performed. At the time of system operation, selecting addressing is performed using the address in the memory. For example, when performing the selecting addressing with the address 003 from the central control device 1, the controlled device 6 whose device-specific address is C0003 is selected and controlled. When the selecting addressing is performed with the address 7A, the device-specific address is changed from C0001 to C008B. That is, the controlled devices 6 up to this point are selected and controlled. The address length in the present embodiment indicates 20 bits when the first two bits of the address are "11", 12 bits when the address is "00", and 8 bits when the first two bits are "01".

In the CATV system, the service content (purpose) or scale may be changed, and the frequency of addition or relocation of the controlled device 6 is relatively high, so that the address currently used cannot be used continuously. There is. Even in such a case, the present invention does not change the unique address of each controlled
Each time the system is started, there is an advantage that the system can be operated with a plurality of addresses stored in the controlled device 6 and in which there are duplicates among the plurality of controlled devices.

Although the above embodiment has been described only in the case where the controlled device 6 is the terminal device 5, the controlled device 6 may be the relay amplifier 2 in the present invention. As a result, the central control device 1 performs information communication with each of the relay amplifiers 2, 2,..., And can know the temperature and abnormality in each of the relay amplifiers 2, 2,.

[Effects of the Invention] As described above, the present invention performs the selecting addressing by the address unique to the controlled device every time the system is started, and separately from the address unique to the controlled device, the service contents (purpose) or scale of the system. In the controlled device, a plurality of addresses where there are duplicates among the plurality of controlled devices, which are organized according to the controlled device, can be selected and controlled by the stored address during system operation, so that the controlled device can be controlled. Can flexibly deal with system expansion changes without changing the unique address of the system.

[Brief description of the drawings]

FIG. 1 is a system diagram of a CATV system. DESCRIPTION OF SYMBOLS 1 ... Central control device, 2 ... Relay amplifier, 3 ... Tap off, 4 ... Relay line, 5 ... Terminal device, 6 ... Controlled device

Claims (1)

(57) [Claims] A central control device, a terminal device or a controlled device of a relay amplifier, and a relay line for connecting the central control device and a controlled device designated by address information transmitted from the central control device are connected to the central control device. In the CATV system that performs selection operation according to the control of the above, each time the system is started, a controlled device is selected based on an address unique to the controlled device, and the service content (purpose) of the system is set separately from the address unique to the controlled device. Address management, characterized in that a plurality of addresses that are duplicated among a plurality of controlled devices, which are organized in accordance with each other, are stored in the controlled device, and the controlled device can be selected based on the stored address during system operation. Method.