JPH096495A - Bus connection control system - Google Patents

Abstract

PURPOSE: To prevent a specific bus from being shut off owing to the excess of transmission capacity in the case that lots of units are connected via an extension module in the data processing unit of common bus system. CONSTITUTION: Extension input output cards 8 to 10 with respect to common buses 1a to 3a are connected via a switchable bus extension module 15. Furthermore, extension input output cards 11 to 13 with respect to common buses 1b to 3b are connected via a switching enable bus extension module 17. The connection of the common buses 1a to 3a of the extension input output cards 8 to 13 is switched as desired by a switching function of the bus extension modules 15, 17 and the concentration of the specific common bus is distributed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bus connection control system, and more particularly to a bus connection control system for performing bus connection control between these units in an information processing apparatus or the like which is composed of a plurality of units each of which is of a common bus system It is about.

[0002]

2. Description of the Related Art In a data processing apparatus, a structure is adopted in which input / output cards having various functions are sequentially connected to a common bus for function expansion.

For example, as shown in FIG. 4, three common buses 1 to 3 are provided. In addition to the input / output cards 5 to 7, further input / output cards 8 to 13 are provided for the common buses. When a system is configured by additionally connecting a plurality of cards, the input / output cards 8 to 13 to be added are connected to the common bus via the bus expansion modules 20, 21 and the like.

The card shown in FIG. 4 is a switch card (SW card) and has a function of switching and connecting the three common buses 1 to 3 to an internal system bus (not shown).

[0005]

In such a conventional common bus system, when the number of cards using the same common bus increases and the number of cards increases, the transmission capacity of the common bus is insufficient and the bus is blocked. become.

The example of FIG. 4 shows an extreme case where all the I / O cards 5 to 13 use only one common bus 3. In such a case, the common bus 3 is used. Is blocked. That is, although there is a transmission capacity of the common bus of the entire system (common buses 1 and 2), if it exceeds the transmission capacity of the common bus 3, the common bus 3 cannot be expanded as a system anymore.

As an example of such a conventional technique, Japanese Patent Laid-Open No.
See, for example, JP-A-2-137654.

Therefore, the present invention has been made to solve the above problems of the prior art, and an object of the present invention is to provide a bus connection control system capable of efficiently using the transmission capacity of a common bus. To provide.

[0009]

According to the present invention, each of the first and second units has a plurality of common buses and a plurality of input / output cards connected to these common buses, A bus connection control system for controlling connection of each of the common buses of a second unit to each of the common buses of the first unit, wherein the second unit connects each of the common buses of its own unit to the first bus. The bus connection control system is characterized in that it has bus switching means which can be switched and connected to each of the plurality of common buses of the unit without overlapping each other.

Further, according to the present invention, the first to nth (n is 3)
Each of the units above has a plurality of common buses and a plurality of input / output cards connected to these common buses,
Connecting each of the nth common buses to each of the common buses of the n-1th unit, and connecting each of the common buses of the n-1th unit to each of the common buses of the n-2th unit. A bus connection control system for sequentially controlling the connection of each of the common buses of the second unit to each of the common buses of the first unit. Each of the second to nth units has a bus switching means capable of switching and connecting each of the common buses of its own unit to each of the common buses of the first to nth units without overlapping each other. A bus connection control system characterized by having.

[0011]

A common bus is managed in each expansion unit having an input / output card, and a bus expansion module for switching and controlling the connection state of the common bus is provided in the expansion unit. The transfer data of each input / output card in the above is efficiently switched and transferred.

[0012]

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

FIG. 1 is a system block diagram of an embodiment of the present invention. 1, the same parts as those in FIG. 4 are designated by the same reference numerals. In this example, the first to third units a to have a plurality of input / output cards and three common buses, respectively.
3 shows a system in which c is connected to each other to expand the function.

The first unit a is a common bus 1a, 2a,
A switch card (SW card) 4 connected to 3a,
It has input / output cards 5 and 6 connected to the common bus 3a and a bus expansion module master card 14 having an interface function between the common buses 1a to 3a and the inter-unit connection cable 100.

The second unit b is a common bus 1b, 2b,
3b and input / output cards 8 and 9 connected to the common bus 3b
And common buses 1b to 3b and unit-to-unit connection cable 10
0 has a bus expansion module slave card 15 having an interface function, and a bus expansion module master card 16 having an interface function between the common buses 1b to 3b and the unit connection cable 101.

The third unit is common to 1c, 2c and 3c.
And the input / output cards 11 to 13 connected to the common bus 3c
And the common buses 1c to 3c and the unit-to-unit connection cable 10
1 and a bus expansion module slave card 17 having an interface function with the CPU 1.

A bus expansion module master card 14,
16 mainly has an output control to the common bus of the host unit and a main signal relay function. In addition, slave cards 15 and 17
Has the output control to the common bus of the unit in which it is mounted, the switching function of the common bus in the unit, and the main signal relay function.

FIG. 2 is a block diagram showing a concrete example of these master cards and slave cards. In the figure, a cable 100 connecting between the unit a (upper unit) and the unit b (lower unit) of FIG. An example of a master card 14 and a slave card 15 that form an interface with the
Of course, the same configuration is also obtained.

Referring to FIG. 2, the bus expansion module master card 14 is a host unit a in which it is mounted.
Data bus interface 141 for interfacing downlink data from the three common data buses 1a to 3a
And a data bus interface 142 that similarly interfaces upstream data to the common data buses 1a to 3a.
And a bus demultiplexing control unit 143 for demultiplexing / demultiplexing each of the three data with respect to these data bus interfaces 141 and 142, and a pair cable 10 for connecting between units
The inter-package (unit) interface 144 connected to 0 and the data bus interface 142 are controlled according to a control signal from the system so as to eliminate the overlap of the upstream data to the common buses 1a to 3a on the time slot. It has a bus control unit 145.

The bus expansion module slave card 15 has a data bus interface 151 for interfacing downlink data to the three common data buses 1b to 3b of the unit b in which it is mounted, and the common bus 1b to 3b.
A data bus interface 152 for interfacing upstream data from 3b; a bus switching control unit 153 for switching and controlling which of the three data buses 1b to 3b is connected to each of the upstream data and the downstream data;
A bus demultiplexing unit 1 for demultiplexing / demultiplexing each of three data with respect to these data bus interfaces 151, 152.
54 and an interface 155 between packages (units) connected to the pair cable 100 for connecting between units.
According to the control signal from the system, the common bus 1c ~
It has a bus control unit 156 that controls the data bus interface 151 and controls switching of the bus switching control unit 153 so as not to overlap the downlink data of 3c on the time slot.

FIG. 3 is an equivalent system connection diagram when the expansion units in the embodiment of the present invention shown in FIGS. 1 and 2 are connected by a bus expansion module master card and a slave card, respectively. As can be seen by comparing with the conventional example of FIG. 4, in the conventional example of FIG.
Even if 3 to 3 are expanded and connected, the common buses 1 to 3 are simply extended, the transmission capacity of each common bus 1 to 3 does not change, and the input / output card is connected beyond the transmission capacity of each common bus. You cannot do it. However, in the present invention, as shown in FIG. 3, in the slave cards 15 and 17 of the bus expansion module, the bus switching is performed by the bus switching control unit so that when the bus 1a is frequently used, the bus is switched to the buses 2a and 3a. And input / output to / from the common bus in the basic unit (top unit) a
It can be other than a.

By doing so, it is possible to eliminate the blockage of the common bus by the basic unit a and effectively use the entire transmission capacity of the common bus of the system.

In the above embodiment, two expansion units, b and c, which are subordinate to the basic unit a are shown, but it is clear that the invention can be applied to two or more units in general.

[0024]

As described above, according to the present invention, the bus expansion module in each unit is provided with the bus switching function, so that the blockage of the bus can be suppressed and the transmission capacity of the common bus of the entire system can be effectively utilized. There is an effect.

[Brief description of drawings]

FIG. 1 is a system block diagram of an embodiment of the present invention.

2 is a block diagram showing a specific example of a master card and a slave card of the bus expansion module of FIG.

FIG. 3 is an equivalent system connection diagram of the embodiment of the present invention.

FIG. 4 is an equivalent system connection diagram of a conventional example.

[Explanation of symbols]

ac unit 1 to 3 common bus 4 switching card 5 to 13 input / output card 14,16 bus expansion module master card 15,17 bus expansion module slave card 100, 101 pair cable for unit connection 141, 142, 151, 152 Data bus interface 143,154 Bus demultiplexer 144,155 Inter-package interface 145,156 Bus controller 153 Bus switching controller

Claims (4)

[Claims] 1. Each of the first and second units has a plurality of common buses and a plurality of input / output cards connected to these common buses, and each of the common buses of the second unit is A bus connection control system for controlling connection to each of the common buses of the first unit, wherein the second unit connects each of the common buses of its own unit to each of the plurality of common buses of the first unit. A bus connection control system having bus switching means that can be switched and connected without overlapping each other. 2. The connection cable between the first and second units is a pair wire cable, and the second unit is provided between the bus switching means and the pair wire cable to control bus demultiplexing. 2. The demultiplexing means for performing demultiplexing, and the first unit has demultiplexing means for demultiplexing the bus, which is provided between the own common bus and the pair cable. Bus connection control system. 3. The first to n-th units (n is an integer of 3 or more) each have a plurality of common buses and a plurality of I / O cards connected to these common buses, Each of the common buses is connected to each of the common buses of the n-1th unit, and each of the common buses of the n-1th unit is connected to each of the common buses of the n-2th unit. A bus connection control system for sequentially performing this connection and finally controlling connection of each of the common buses of the second unit to each of the common buses of the first unit. Each of the n units has a bus switching means capable of switching and connecting each of the common buses of its own unit to each of the common buses of the first to (n-1) th units without overlapping each other. And a bus connection control system. 4. The connection between the units is a pair wire cable, and each of the units has a bus demultiplexing unit that forms an interface between the pair wire cable and the common bus. Item 3. The bus connection control system according to Item 3.