JPH08265346A - Bus wiring - Google Patents

Abstract

PURPOSE: To increase signal transmission rate on a bus wiring and to improve the working efficiency of a bus by connecting load wiring boards in point-to- point, separating a bus which transmits a signal from the one which receives data and providing a bus for state notification for the load wiring board. CONSTITUTION: The load wiring board 1a is connected to each of the load wiring boards 1b-1n by signal connection in one to one. The signal connection in such type is performed by reporting bus access from the load wiring board 1a to the load wiring board 1b via a signal wiring 2a. When the load wiring board 1b accepts the bus access, a notice being set in a communicating state is reported to each load wiring board via a signal bus wiring 10 for load state notification. The wiring board 1b issues a response to the wiring board 1a. The wiring board 1a issues the notice to other load wiring boards 1c-1n during that notification. In such a case, since the load wiring board 1a is connected to other load wiring boards 1b-1n in one to one, fast signal transmission is performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bus wiring for connecting a plurality of load wiring boards connected to signal wiring.

[0002]

2. Description of the Related Art FIG. 3 shows a conventional bus wiring configuration. In the conventional bus wiring, one bus wiring 20 has a plurality of load wiring boards 1
, 1n are connected, and signals on the bus line 20 are also used bidirectionally.

[0003]

In such a wiring configuration of the bus, the characteristic impedance of the signal wiring decreases as the number of load wiring boards connected to one signal wiring increases, resulting in a decrease in the characteristic of the connector connection. Since reflection due to impedance mismatch increases and the ringing of the waveform accompanying the reflection decreases transmission performance, it is difficult to increase the signal transmission speed of the bus wiring. Further, in the conventional bus configuration, a single signal line is shared by a plurality of load wiring boards and is used bidirectionally. Therefore, a response from a certain load wiring board issues a bus access command. Until it returned, even if another load wiring board occupies this bus wiring and tries to access the bus, it cannot be accessed, and the bus usage efficiency is not high.

The present invention has been made in order to solve the above-mentioned problems for increasing the speed of a bus, and provides a bus wiring for improving the signal transmission speed of the bus wiring and for improving the bus usage efficiency. To aim for things.

[0005]

In order to achieve the above object, the present invention provides a bus signal wiring set on a backplane attached to a rack and a load wiring board connecting connector connected to the bus signal wiring. In the bus wiring that connects multiple load wiring boards to the backplane and transmits / receives signals between arbitrary load wiring boards via the point-to-point connection between the load wiring boards and the signal transmission. And a bus for receiving data are separated from each other, and a bus for notifying the state of the load wiring board is provided.

[0006]

In the bus wiring according to the present invention, the load wiring boards connected to the bus wiring are connected in a one-to-one manner, and the signals on the bus wiring are separated in one direction to notify the status of each load wiring board. The signal wiring bus is commonly used.

As described above, the bus wiring is provided between the load wiring boards by one.
The connection to the pair 1 facilitates the design of the characteristic impedance of the wiring system and facilitates the improvement of the signal transmission speed. Further, since the bus wiring is separated in one direction, it is possible to avoid a decrease in bus usage efficiency in shared use of the bus. Furthermore, even while a certain load wiring board is communicating with each other, it is possible to communicate with other wiring boards, so that the bus usage efficiency is improved, and the status of each load wiring board is a common signal wiring for status notification. Apply the bus to improve the transmission efficiency of common signals.

[0008]

Embodiments of the present invention will now be described in detail with reference to the drawings. 1 is a first embodiment of the present invention, a bus signal wiring set on a backplane mounted on a rack,
A bus wiring is shown in which a plurality of load wiring boards are connected to the backplane via a load wiring board connecting connector connected to the bus signal wiring, and signals are transmitted and received between arbitrary load wiring boards. In other words, the load wiring board 1a corresponds to a communication control unit, and the others correspond to the load wiring boards 1b, 1c, ..., 1n controlled by the load wiring board 1a. In the figure, from the load wiring board 1a to the load wiring boards 1b, 1c, ...
There is a one-to-one signal connection to 1n. In the signal connection in this form, for example, the load wiring board 1a notifies the load wiring board 1b of the bus access via the bus signal wiring (bus for transmitting a signal) 2a. When the load wiring board 1b accepts the bus access, it notifies each load wiring board via the load status notification signal bus wiring 10 that the communication state has been entered. Load wiring board 1b responds to load wiring board 1a via bus signal wiring (bus for receiving data) 3a. During this communication, the load wiring board 1a is connected to another load wiring board 1
Communication with c, ..., 1n is possible. In this case, the load wiring boards that have entered the mutual communication state notify the load wiring boards of the load state via the status notification signal bus wiring 10. Further, the load wiring boards 1a, 1b, 1c, ..., 1n are connected point-to-point, that is, the load wiring board 1a and the other load wiring boards 1b, 1c ,. Therefore, high-speed signal transmission becomes possible.

FIG. 2 shows a second embodiment of the present invention, in which a bus signal wiring set on a backplane mounted on a rack and
The bus wiring for connecting a plurality of load wiring boards to the backplane via the load wiring board connecting connector connected to the bus signal wiring and transmitting and receiving signals between arbitrary load wiring boards is shown. In the second embodiment, each load wiring board 1a, 1
The mode in which b, 1c, ..., 1n serves as a communication control unit is shown.
In the figure, the load wiring boards 1a, 1b, 1c, ..., 1n are connected point-to-point, that is, there is a one-to-one signal connection wiring between the load wiring boards 1a, 1b, 1c ,. To be done. For example, the load wiring board 1a notifies the load wiring board 1b of the bus access via the bus signal wiring (bus for transmitting a signal) 21ab. When the load wiring board 1b understands the communication, the load wiring boards 1a and 1b notify the other load wiring boards 1c, ..., 1n via the load status notification signal bus wiring 10 that the load status has entered the communication state. At the same time, load wiring board 1b responds to load wiring board 1a via bus signal wiring (bus for receiving data) 31ab. The load wiring board 1a transfers data at high speed to the load wiring board 1b via the bus signal wiring 21ab, and also transfers response data via the bus signal wiring 31ab.
The load status notification signal bus wiring 10 enables independent signal connection even in other load wiring boards that are not in communication. The load wiring boards that have entered the mutual communication state notify each load wiring board via the load state communication signal bus wiring 10. Since this notification can be handled as a one-way signal to each load wiring board, a complicated protocol is not required, and each load wiring board need only read the notified information.

[0010]

As described above, according to the bus wiring of the present invention, since the loads are connected in a one-to-one relationship, high-speed signal transmission between the load wiring boards is possible and the load usage state is improved. Since the notification is made on an individual bus, there is an effect that bus usage efficiency is increased.

[Brief description of drawings]

FIG. 1 is a configuration explanatory view showing a bus wiring according to a first embodiment of the present invention.

FIG. 2 is a configuration explanatory view showing a bus wiring according to a second embodiment of the present invention.

FIG. 3 is a configuration explanatory view showing a conventional bus wiring configuration.

[Explanation of symbols]

1a, 1b, 1c, ..., 1n ... Load wiring board, 2a, 2
b, ..., 2n, 21ab, 21ac, ..., 21an, 2
2bc, ..., 22bn, 23cn ... Bus signal wiring, 3
a, 3b, 3c, ..., 3n, 31ab, 31ac ,.
31an, 32bc, ..., 32bn, 33cn ... Bus signal wiring, 10 ... Load status notification signal bus wiring, 20 ... Bus wiring used bidirectionally.

Claims (1)

[Claims] 1. A plurality of load wiring boards are connected to the backplane via a bus signal wiring set on a backplane attached to a rack and a load wiring board connecting connector connected to the bus signal wiring, In bus wiring for transmitting and receiving signals between arbitrary load wiring boards, connect the load wiring boards point-to-point, separate the bus for transmitting signals and the bus for receiving data, and Bus wiring having a status notification bus.