JP2001167022A - Data transfer system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a PCM data transfer system improved in the transfer speed of data. SOLUTION: The PCM data of a computer system are directly received from a data bus 5 to a buffer 3 for receiving, for example, of an NIC 2. The buffer 3 for receiving, for example, of the NIC 2 continuously receives the PCM data until that buffer becomes full. While the buffer 3 for receiving, for example, receives the data, another buffer 4, for example, is used for transmitting. In the buffer 4, for transmitting, for example, converting processing of PCM data to the data format of a LAN 6 is performed inside the buffer 4, for example. When the buffer 4 for receiving, for example, under fetching the PCM data from the data bus 5 becomes full, a CPU 1 instructs the stop of data fetching of that buffer 3, for example. Next, the buffer 3, for example, used for receiving is used for transmitting this time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a data transfer system, and more particularly to a data transfer system for transferring PCM data from a data bus of a computer to a LAN (local area network).

[0002]

2. Description of the Related Art As shown in FIG. 2, a computer system comprises a central processing unit (CPU) (central processing unit 1 and a central processing unit (CPU)).
It has a memory 10 which is a main storage device for storing control programs and data of U1. Also, peripheral devices,
Terminal device, input / output device (none shown), CPU1
And a data bus 5 for interconnecting the memory 10 and the like.

Further, it may be necessary to transfer PCM data of a computer system to a LAN 6 via an NIC (network interface controller, large-scale semiconductor integrated circuit device; LSI chip, a kind of gateway) 2. In this case, conventionally, as shown in FIG. 2, the PCM data is first temporarily buffered in the buffer memories 8 and 9 on the data bus 5. Next, the buffer memory, for example, the PCM data stored in 8 is monitored by the CPU 1 and transferred to the buffer memory 7 of the NIC via the NIC 2.

During this time, the PCM data of the computer system is stored in a buffer memory, for example, 9 and then transferred to the buffer memory 7. The data is transferred from the buffer memory 7 to the LAN 6. Therefore, LA
It will be buffered twice before the data is processed and transferred on N6.

[0005]

A conventional PC shown in FIG.
In the M data transfer system, the LA of PCM data
As for the transfer to N, there is a problem that the transfer speed of data is reduced. That is, the PCM data is temporarily buffered in the buffer memory on the data bus, and the data is stored in the buffer memory on the data bus.
Since the data is transferred to the buffer memory of the NIC via the IC, two buffer memories are used, and the data flow is wasteful and takes time.

An object of the present invention is to provide a PCM data transfer system having an improved data transfer speed.

[0007]

According to the present invention, there is provided a data transfer system for transferring data from a computer system to a local area network via a gateway, wherein the data transfer system temporarily stores transfer data in the gateway. A data transfer system characterized by providing a buffer is obtained.

The double buffer is composed of two buffer memories, one of which is used as a receiving buffer for storing data from the computer system, and the other of which is used as a transmitting buffer. The stored data is transmitted to a local area network.

Further, when the receiving buffer memory becomes full, the receiving buffer memory is used for transmitting, and the transmitting buffer memory is replaced for receiving. The transmission buffer memory converts the transfer data from the computer system into a signal format for the local area network.

The operation of the present invention is as follows. Provide double buffer memory in NIC, and use one buffer for C
The transfer data from the PU is directly taken in, the data is processed in the other buffer, and the processed data is transferred to the LAN. In this way, the use location and the use method of the buffer are improved in the transmission path of the transfer data on the LAN.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of an embodiment of a PCM data transfer system according to the present invention, and the same parts as those in FIG. 2 are denoted by the same reference numerals. In FIG. 1, a computer system related to the present invention includes a CPU 1 as a main body, and a memory (not shown) as a main storage device for storing a control program, data, and the like for the CPU 1.
And Further, it is configured to have a data bus 5 for mutually connecting a peripheral device, a terminal device, an input / output device (neither is shown), a CPU 1, a memory, and the like.

Further, in the PCM data transfer system according to the present invention, the PCM data of the computer
NIC2 to transfer to N6. Furthermore, it includes double buffer memories 3 and 4 whose applications can be exchanged between receiving and transmitting, and a LAN 6 for transferring PCM data.

The operation of the embodiment of the present invention will be described with reference to FIG. When transferring the PCM data of the computer system to the LAN 6, the buffer memories 3 and 4 of the NIC 2 are used as double buffers, and one buffer, for example, 3 is a reception buffer, the other is
For example, 4 is used as a transmission buffer.

The PCM data of the computer system is
From the data bus 5 to the receiving buffer of the NIC 2, for example, 3
Receive directly to. NIC2 reception buffer, for example, 3
Keeps receiving PCM data until its buffer is full. While the receiving buffer, for example 3, is receiving,
The other buffer, for example 4, is used for transmission.

In the transmission buffer, for example, 4, the PCM data is converted into the LAN 6 data format in the buffer, for example. That is, for example, L
When the AN 6 is an Ethernet, the data is converted to data in a data format format for the Ethernet bus and
6 to be transmitted.

When a receiving buffer for taking in PCM data from the data bus 5, for example, 3 becomes full, C
PU1 suspends and instructs the buffer, for example, to take in the data of 3. Next, the buffer used for reception, for example, 3 is used (alternately) for transmission this time. In the transmission buffer storing the PCM data, for example, 3, data formatting is performed, and the data is transmitted to the LAN 6 which is an Ethernet bus.

At this time, data is fetched using the buffer used for transmission, for example, 4 for reception. Buffer used for reception, for example, 4
When is full, switching (alternating) processing between the transmission buffer and the reception buffer is performed. Switching (replacement) between the transmission buffer and the reception buffer when the buffers 3 and 4 are full is performed according to an instruction from the CPU 1.

Although the transfer data is described using PCM data as an example, it is obvious that the transfer data is not limited to the PCM data and may be digital data of various formats.

[0019]

As described above, according to the present invention, there is an effect that high-speed PCM data transfer processing to the LAN via the NIC is enabled. In addition, there is no need to provide a buffer memory in the data bus, so that there is an effect that simplification of hardware is realized. Further, since the processing on the network is simplified, there is an effect that the reliability of data is improved. Furthermore, no buffer is provided on the data bus, and the
By receiving and processing the CM data, there is also an effect that the data in the buffer of the NIC can be directly accessed from the CPU.

[Brief description of the drawings]

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

FIG. 2 is a block diagram of an example of a conventional PCM data transfer system.

[Explanation of symbols]

 1 CPU 2 NIC 3, 4 Buffer memory 5 Data bus 6 LAN

Claims (4)

[Claims] 1. A data transfer system for transferring data from a computer system to a local area network via a gateway, comprising:
A data transfer system comprising a double buffer for temporarily storing transfer data. 2. The double buffer is composed of two buffer memories, one of which is used as a receiving buffer for storing data from the computer system, and the other of which is used as a transmitting buffer. 2. The data transfer system according to claim 1, wherein the stored data is transmitted to a local area network. 3. When the receiving buffer memory is full, the receiving buffer memory is used for transmission,
3. The data transfer system according to claim 2, wherein said transmission buffer memory is replaced for reception. 4. The data transfer system according to claim 2, wherein said transmission buffer memory converts transfer data from said computer system into a signal format for said local area network.