JPH06274451A - Bus system - Google Patents

Abstract

PURPOSE:To shorten a data transferring time to plural units. CONSTITUTION:A transmission side unit 10 is equipped with a transfer system switching signal transmitting means 7 which transmits a transfer system switching signal 40 for instructing a transfer system switching to plural reception side units, and a data transmitting means 5 which transmits data of plural byte width to plural reception side units 11-14. Also, each reception side unit 11-14 is equipped with transfer system switching signal receiving means 80-83 which receive the transfer system switching signal 40, data receiving means 60-63 which receive the data of plural byte width transmitted from the transmission side unit accord to the instruction of the transfer system switching signal receiving means 80-83, and data selecting mean 90-93 which select only the data at the preliminarily set byte position from among the received data of the plural byte width.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bus system in which a plurality of units are connected to a data transfer bus having a width of a plurality of bytes, and data of a width of a plurality of bytes is transferred between the units.

[0002]

2. Description of the Related Art Conventionally, in this type of bus system, when data is transferred between constituent units, the unit to be transferred and the unit to be transferred are in a one-to-one correspondence, and the data is transferred individually. .

[0003]

In the above-mentioned conventional bus system, when different data is transferred to a plurality of units, it is necessary to occupy each bus and transfer data in order to transfer a plurality of units. However, the bus occupancy time for that purpose is required individually, and there is a problem that it takes more time for data transfer.

[0004]

A bus system according to the present invention is a bus system in which a plurality of units are commonly connected to a data transfer bus having a multi-byte width, and data of multi-byte width is transferred between the units. The transmitting side unit includes a transfer mode switching signal transmitting means for transmitting a transfer mode switching signal for instructing a plurality of receiving side units to transfer mode switching, and a data transmitting means for transmitting data of a plurality of bytes width to the plurality of receiving side units. Each receiving side unit has a transfer method switching signal receiving means for receiving the transfer method switching signal, and a plurality of bytes of data transmitted from the transmitting side unit according to an instruction from the transfer method switching signal receiving means. And a data selection means for selecting only the data at a preset byte position from the received multi-byte width data. A bus system characterized by comprising means for transmitting the data having a width of a plurality of bytes to a plurality of the receiving units at the same time, and each of the receiving units can validate only the data at an arbitrary byte position. And

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1 showing an embodiment of the present invention,
In the present embodiment, 10 is a transmission side unit, 11-14.
Is a receiving side unit, 5 is a data transmitting means, 60 to 63 are data receiving means, 7 is a transfer method switching signal transmitting means, 80
˜83 is a transfer method switching signal receiving means, 90 to 93 is a data selecting means, 20 is a 4-byte width data bus, 21 is a control bus, 40 is a transfer method switching signal, 41 is a transfer start instruction signal, and 42 to 45 data. Selection signal, 46-49
This is a reception system switching signal.

FIG. 2 shows a 4-byte data receiving unit 1
1 is a block diagram showing an image of data selection in the reception side unit 11 when it is transferred to 1, and FIG. 3 is a block diagram showing an image of data distribution from the transmission side unit 10 to each of the reception side units 11 to 14. FIG. 4 is a time chart showing the relationship between the control signals.

In FIG. 1 and FIG. 2, the transmission side unit 1
0 and the receiving side units 11 to 14 normally transfer data with a width of 4 bytes via the data bus 20. The data transmission means 5 in the transmission side unit 10 is means for transmitting data on the data bus 20, and the data reception means 60-63 in the reception side units 11-14 are means for receiving data on the data bus 20 and above, respectively. Is.

The transfer method switching signal transmitting means 7 is means for transmitting a transfer method switching signal 40 to the receiving side units 11 to 14 instructing that the normal transfer is switched to the data distribution transfer. The transfer method switching signal receiving means 80 to 83 in the receiving side units 11 to 14 are means for receiving the transfer method switching signal 40 instructing switching to the data distribution, and the data selecting means 90 to 93 are set in advance. It is a means to select only the data at the byte position. Here, the data distribution transfer means that the transmission side unit 10 simultaneously receives data having a width of a plurality of bytes to a plurality of reception side units 11 to 14, and the reception side units 11 to 14 have respective byte positions of transfer data. A transfer in which only data is valid.

Next, the operation will be specifically described.

In FIG. 1, when the transmission side unit 10 performs distribution transfer to the reception side units 11 to 14, first, the transfer system switching signal transmission means 7 performs data distribution transfer to each of the reception side units 11 to 14. In order to make 14 recognize, the transfer method switching signal 40 for instructing transfer method switching is transmitted to the transfer method switching signal receiving means 80 to 83 in each of the receiving side units 1 to 14 via the control bus 21, and the transmitting side. In the unit, the transfer method switching signal means 7 sends the transfer method switching signal 40 to the data transfer means 5.

The transfer method switching signal receiving means 80 to 83 receive the transfer method switching signal 40, recognize that the transmitting side unit 10 performs data distribution transfer, and receive the receiving method switching signal 4.
6 to 49 are transmitted to the data receiving means 60 to 63, and the data selection signals 42 to 45 are transmitted to the data selecting means 90 to 93. The data receiving means 60 to 63 recognize the data distribution transfer by the received reception mode switching signals 46 to 49,
All the data receiving means 60-63 prepare to receive data. The data selecting means 90 to 93 prepare to select the data at the predetermined byte position by the sent data selecting signals 42 to 45.

When the data transmitting means 5 receives the transfer method switching signal 40 from the transfer method switching signal transmitting means 7, each data to be transmitted to each of the receiving side units 11 to 14 is 4 bytes for 4 units in a predetermined order. The data is collectively transmitted to the data bus 20, and at the same time, the transfer start instruction signal 4
1 is transmitted to the control bus 21. The data receiving means 60 to 63 receive the start instruction signal 4 from the control bus 21.
1 is received and valid data is received from the data bus 20. The data selecting means 90 to 93 are the data receiving means 60 to
One-byte data at each preset byte position of the data sent from 63 is selected by the data selection signals 42 to 45 and sent to the data processing means not shown here.

In FIG. 2, the transfer system switching signal transmitting means 7 transmits the transfer system switching signal 40 to the control bus 21, and the transfer system switching signal 40 is transmitted from the control bus 21.
Is received from the transfer method switching signal receiving means 80. In addition, in the transmission side unit 10, the transfer method switching signal transmission means 7 transmits the transfer method switching signal 40 to the data transfer means.
The transfer system switching signal receiving means 80 receives the reception system switching signal 46.
Is transmitted to the data receiving means 60, and the data selection signal 42 is transmitted to the data selecting means 90. In response to the transfer method switching signal 40, the data transmitting means 5 transmits the data to be transmitted to the receiving side unit 11 to the data bus 20 and the transfer start instruction signal 41 to the control bus 21.

The data receiving means 60 uses the transfer start instruction signal 4
In response to 1, data is received from the data bus 20, the received data is divided into bytes, and each byte is sent to the data selecting means 90. The data selection means 90 validates the data at the byte position preset by the data selection signal 42 and sends it to the data processing means (not shown).

In FIG. 3, the transmission side unit 10 sends data A, B, C, and data to the reception side units 11 to 14, respectively.
When transferring D, the sending unit 10 sends the data A,
B, C and D are collectively transmitted to the data bus 20. The transmission side unit 11 selects only the data A from the data A, B, C and D, the transmission side unit 12 selects only the data B, and the transmission side unit 13 selects only the data C,
The transmitting unit 14 selects only the data D. Also,
Even when a plurality of data distribution transfers are performed, the transfer data A to Z in the transmission side unit 10 is the same as the transfer at one time in the reception side units 11, 12, 13, and 14, respectively. , Column C data and column D data are selected.

In FIG. 4, when the transfer system switching signal 40 is transmitted from the transmitting side unit 10, the transfer system switching signal receiving means 80 to 83 switch the transfer system to the data selection signals 42 to 45 and the receiving system switching signals 46 to 49. The signal 40 is generated in response to the signal 40, and the data transfer means 5 transfers the transfer start instruction signal 4
1 is generated in response to the transfer method switching signal 40, and the data distribution transfer data is transmitted by the same dimming as the transfer start instruction signal 41. The data receiving means 60-63 recognize the data distribution transfer by the reception method switching signals 46-49, and at the timing of receiving the transfer start instruction signal 41 transferred via the control bus 21, the data receiving means 60-6.
3 receives the data. Then, the data selection signal 42-
45, the data selecting means 90 to 93 select only the data at the preset byte position.

[0017]

As described above, according to the present invention, the transmitting side unit simultaneously transmits the data having a width of a plurality of bytes to the plurality of receiving side units, and the receiving side unit respectively receives only the data at a specific byte position. By providing the data transfer means to be effective, the transfer time can be shortened and the bus can be effectively used.

[Brief description of drawings]

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

FIG. 2 is a diagram showing how data is selected in a receiving side unit in the embodiment of FIG.

FIG. 3 is a diagram showing an example of data distribution from a transmission side unit to a reception side unit in the embodiment of FIG.

FIG. 4 is a timing chart of the embodiment shown in FIG.

[Explanation of symbols]

 10 transmission side unit 11-14 reception side unit 20 data bus 21 control 40 transfer method switching signal 41 transfer start instruction signal 42-45 data selection signal 46-49 receiving method switching signal 5 data transmitting means 60-63 data receiving means 7 transfer Method switching signal transmitting means 80 to 83 Transfer method switching signal receiving means 90 to 93 Data selecting means

Claims (1)

[Claims] 1. In a bus system in which a plurality of units are commonly connected to a data transfer bus of a multi-byte width and data of a multi-byte width is transferred between each unit, a transmission side unit is a plurality of reception side units. A transfer method switching signal transmitting means for transmitting a transfer method switching signal for instructing transfer method switching, and a data transmitting means for transmitting data of a plurality of bytes width to a plurality of receiving side units, each receiving side unit comprising: Transfer method switching signal receiving means for receiving the transfer method switching signal; data receiving means for receiving data of a plurality of bytes width transmitted from the transmitting side unit according to an instruction of the transfer method switching signal receiving means; There is a data selecting means for selecting only the data at the preset byte position among the byte width data, and the transmitting side unit has a plurality of units. A bus system, wherein byte-width data is simultaneously transmitted to a plurality of the reception side units, and each reception side unit can validate only the data at an arbitrary byte position.