JPS6020778B2 - Composite computer equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a compound computer comprising a plurality of computers, and more particularly to a compound computer device in which the computers are connected by a multiplexed system bus.

In recent years, with the advent of microcomputers, compound computer devices have been adopted in which functions are distributed by organically linking a plurality of computers. Composite computer equipment distributes the functions between each computer, while maintaining operational independence as much as possible, and configures the entire system by combining specialized functional computers in a building block format according to the required functions. It was designed to do so. This complex computer system allows for a flexible system, and in the event of a local failure, only the corresponding function can be excluded, eliminating the need to stop the entire system, thereby improving system reliability. be able to. Furthermore, taking advantage of this feature, depending on the reliability required for the function,
Reliability can be ensured economically by duplicating necessary functions.

FIG. 1 shows an example of a conventional compound computer device. Computers IA and IB are duplexed, and system buses 5A and 58 and system bus interfaces 4A and 4B are also duplexed, so that computer IA, system bus 5A, and system bus interface 4A can be used to connect computer system A or The computer IB, system bus 58, and system bus interface 4B constitute a B-system computer system.

On the other hand, computers 2 and 3 are not duplicated. The redundant computer system uses system bus interface 4.
An interlock is established between A and 4B, and either one is operating. That is, if computer IA of system A is set to regular mode and computer IB of system B is set to standby mode, if computer IA of system A is normal, computer IA side is connected to other computers 2 and 3 that are not duplicated. Therefore, only the system bus interface 4A of the A system becomes active, and the operation of the system bus interface 4B of the B system is inhibited. A series, B
As shown in FIG. 2, the system bus interfaces 4A and 4B of the system consist of a bidirectional bus driver 41, a transmission control circuit 42, and a reception control circuit 43, and a system data bus 51 and a system data bus 51 that constitute the system buses 5A and 5B, respectively. It is connected to the bus control line 52 and enables data transfer between the computers via the system bus. Calculator I
When A detects an abnormality through its self-diagnosis function, it outputs a standby mode request signal to the transmission control circuit 42 of the system bus interface 4A to switch from the normal mode to the standby mode. When the standby mode is entered, the standby mode signal on the A-system bus control line 52 blocks the reception control circuits 43 and transmission control circuits 42 of all system bus interfaces 4A of the A-system, and the bidirectional bus driver 41 becomes non-conductive. That is, the A-based computer system becomes inactive. On the other hand, the transmission control circuit 42 of the B system system bus interface 48
When the transmission control circuit 42 of the A-system bus interface 4A enters the standby mode, the interlock is tripped and if no standby mode request signal is received from the computer IB, it switches from the standby mode to the regular mode. As a result, the standby mode signal on the B-system bus control line 52 disappears, and all the B-system bus interfaces 4B become active.
As a result, the system bus 5B becomes active and the computers IB and 2
, 3 are combined.

In this method, since only one of the duplicated computers IA and IB is actually operating, computer 2
, 3 from IA to IB or 'B to I
When switching to A, a control disturbance occurs. That is, when switching from IA to IB, the computer IB inputs the input at that time,
Since control is started only with information from computers 2 and 3, computer I
This is because there is a possibility that the control content up to that point stored in A may be different. The present invention has been made in view of this current situation, and by giving the same input to the computer in standby 3 as the computer in use and causing the computer in standby to operate in the same way, it is possible to transfer the input from the regular computer to the standby computer. The object of the present invention is to obtain a multifunction computer device that does not cause disturbance in control even when the machine in use is switched from a standby machine to a regular machine.

Embodiments of the present invention will be described in detail below using block diagrams shown in FIGS. 3 and 4.

In Figure 3, computers IA, IB, 2, 3, system bus interfaces 4A, 48, system/bus 54A
, 5B are the same as in FIG. 1, so redundant clarification will be omitted. The non-duplicated computers 2 and 3 and the A-system and B-system system buses 5A and 58 are connected through system bus transmission interfaces 8A and 8B and system bus transmission interfaces 9A and 9B, respectively. Next, a description will be given of data transfer between computers when computer IA is used as a regular computer and IB is used as a standby computer. From computer IA to computer 2
or 3, or when transferring data to both computers 2 and 3, system bus interface 4A of system A,
The system bus 5A and the system bus receiving interface 9A connected to the system bus 5A become active. On the other hand, when transferring data from computer 2 (or 3) to computer IA, system bus transmission interfaces 8A and 88 of both system A and system B connected to computer 2 (or 3), and system bus interface 4A are used. and 4B are respectively active, and calculator 2 (or 3
) to computer IA in system A, but also data transfer from computer 2 (or 3) to computer IB in system B is possible.

By the way, in order to prevent the standby computer from affecting the operation of the computer in use, the duplicated computers do not have a common circuit, so the duplicated computers IA and IB
The operation timings of the two do not necessarily match.

This means that when transferring data from non-duplicated computer 2 (or 3) to a duplicated computer system, it is necessary to absorb the deviation in the operation timing of the duplicated computer system in data transmission control. do. In the present invention, the system bus transmission interfaces 8A and 8B have this function. Next, the configuration and operation of the system bus transmission interface will be explained. As shown in FIG. 4, the system bus transmission interfaces 8A and 8B are composed of a bus driver 81, a transmission control circuit 42, and a buffer circuit 82.
It is connected to. The buffer circuit 82 serves as a data buffer to enable independent control of the system buses 5A and 5B when transmitting data from the computer 2 (or 3), and serves as a data buffer between the system buses 5A and 5B. A data buffer register or a first-in-first-out memory is used, which has a storage capacity determined by the time difference in the operation timing of the data buffer register. Here, a first-in-first-out memory is a memory in which write data and read data are led to separate terminals, and the write operation and read data are controlled independently, and the stored contents are stored in the order in which they were written. It has operating characteristics that are highlighted. As shown in FIG. 4, the system bus reception interfaces 9A and 98 are composed of a bus driver 91 and a reception control circuit 43. Similar to conventional reception control, the bus driver 91 is activated at the timing when data is output to the system data bus 51. An operation is performed to connect the computer and the system data bus 51 by connecting the computer to the system data bus 51. As explained above, the present invention enables both duplex system buses to be active by providing a data buffer section in each transmission interface section so that the transmission control of the transmission interface sections of computers that are not duplexed can be performed independently. This configuration allows the same input information to be given to duplicated computers.

By making both system buses active in this way, the redundant computers will operate based on the same input information, and control will be possible using the output of either the regular or standby computer, so the computer in use will No special processing is required and no control disturbance occurs when switching from a regular-use to a stand-by machine, or from a stand-by machine to a regular-use machine. Moreover, both the redundant computers and system bus are independent in terms of hardware and operation, so even if there is an abnormality in one computer or system bus, it will not affect the other. Not until now. Furthermore, since the duplicated computers operate with the same input information, if the normal control state is stable, both computers will be in the same operating state, so if an abnormality occurs in either one, both computers will operate. By comparing the results, it becomes easier to investigate the content and cause of the abnormality.

In addition, since both system buses are active, it is possible to monitor the operation of the system bus by computers that are not duplicated, so it is possible to detect an abnormality in one of the duplicated computers and an abnormality in each system bus interface section. It can be easily detected and becomes a highly reliable multi-computer hawk. Although the above description has been made with reference to a case where a redundant computer and a system bus are included, the present invention is not limited to duplication, but is also effective when including a triplex or more multiplexed computer and system bus. Needless to say.

[Brief explanation of the drawing]

1 and 2 are block diagrams showing examples of conventional compound computer devices, and FIGS. 3 and 4 are block diagrams showing examples of compound computer devices of the present invention. IA, IB...duplicated computers, 2,
3... Computer not duplicated, 4A, 48
...System bus interface, 5A, 5B""
``System bus, 8A, 8B...System bus transmission interface, 9A, 98...System bus 8-way communication interface, 41...Bidirectional bus driver, 42...Transmission control circuit , 43... Reception control circuit, 51... System data bus, 52... System bus control line, 81, 91... Bus driver, 82.
...Buffer bypass. Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1 Multiplexing is provided by providing multiple computer systems in which computers are connected to a system bus via a bidirectional interface, and a computer that is not multiplexed is connected to a system bus transmission interface for each system bus of each system. and a system bus reception interface, the system bus transmission interface temporarily stores data when a non-multiplexed computer transmits data to the system bus. A compound computer device characterized by being provided with a buffer circuit that buffers deviations in operation timing of system buses of each system.