JPH11284609A - Time compression transmission device and time compression transmission method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain equal communication by leaving from a master slave relation between devices and to change a data quantity of communication by one burst by sending/receiving burst data consisting of header information and data, discriminating an end of a reception period of a received burst signal from received burst data, and sending transmission burst data to other device. SOLUTION: A transmission/reception section 10 receives reception burst data 11, a header data extract section 12 extracts header information 13 including a transmission end flag and a fixed length flag from the reception burst data 11 and data 14, a reception end discrimination section 16 discriminates an end of reception based on the header information 13 and the data 14 and outputs a transmission start signal 17. A transmission burst data generating section 18, upon the receipt of the transmission start signal 17, adds a transmission end flag to data 19 to be sent when transmission is not required after the former transmission and adds a fixed length flag to the data 19 when the data 19 has a fixed length and then outputs resulting transmission burst data 21 to the transmission/reception section 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an apparatus and a method for performing ping-pong transmission on one medium.

[0002]

2. Description of the Related Art High-speed serial bus IEEE1394-1
995 is four electric signal lines (two twisted pair lines)
To realize bidirectional data transmission. In addition, IEEE 1394. which discusses future standards. At the B meeting, a transmission system using two optical fibers is currently being discussed.

[0003] It is desired to transmit an IEEE 1394 signal using one optical fiber. To realize bidirectional communication on one optical fiber, a time division multiplexing method in which the transmission direction is switched in a time division manner or a transmission method. There is a frequency multiplexing method using light of different wavelengths depending on the direction.

[0004] A main method of two-way communication using the time division multiplexing method is a ping-pong transmission method (official name: time division direction control transmission method) used in ISDN and the like. Conventional ping-pong transmission is a method of repeatedly transmitting and receiving a fixed amount of data at a fixed ping-pong cycle, as shown in FIG. However, the conventional ping-pong transmission has a problem that the transmission speed is semi-fixed.

As a prior art of a ping-pong transmission system in which the transmission speed is made variable, there is one disclosed in Japanese Patent Application Laid-Open No. 9-98200. In this prior art, three methods are shown.

First, when the master station changes from the transmission state to the reception state, and the slave station has no received data for a certain period of time, the slave station transmits a fixed amount of data from the slave station. How to return to. Second, as shown in FIG. 7, a method is used in which a flag is set at the head of the master station transmission data, and the master station or the slave station becomes the transmitting side in the next burst time. Third, as shown in FIG. 8, a training period is provided,
This is a method for adjusting the station according to the transmission / reception ratio set by the master.

[0007]

However, any of the above methods is based on the fixed or semi-fixed master-slave relationship of the station (equipment). Ping-pong transmission is often desirable.

In particular, in the case of IEEE 1394, since there is no fixed center machine and the bus configuration changes dynamically, equal ping-pong transmission which does not assume a master-slave relationship between devices is desirable.

One of the problems to be solved by the present invention is 1
In the case of one-to-one communication, the object is to provide equal communication that does not assume a master-slave relationship between devices.

In each of the above methods, the time of one burst is fixed, but ping-pong transmission in which the time of one burst can be changed is desirable in many applications.

In particular, in the case of IEEE 1394, it is desirable to lengthen one burst in the data transfer period in order to transmit a large amount of data in one direction at a high communication speed, while the other periods are each longer. In order to frequently exchange signals indicating the state of the device, it is desirable to shorten the time of one burst as much as possible.

The second problem to be solved by the present invention is as follows.
It is to provide ping-pong transmission capable of changing the amount of data that can be transmitted in bursts.

[0013]

A ping-pong transmission device according to the present invention (Claim 1) comprises: a transmission / reception unit for transmitting and receiving burst data including at least header information and data between at least two devices; A header data extraction unit for extracting header information and data from the received burst data received by the transmission / reception unit; and receiving the reception burst signal from the header information and data extracted by the header data extraction unit. At least a reception end determination unit that determines the end of a period, and a transmission burst data generation unit that generates transmission burst data by adding header information based on the data to be transmitted, and transmits the transmission burst data to the transmission / reception unit. Receiving the determination result of the end of the reception period determined by the reception end determination unit, transmitting the transmission burst data from the transmission / reception unit to another By transmitting to the device, it is possible ping-pong transmission, thereby solving the above problems.

A ping-pong transmission device according to the present invention (claim 2) includes a reception data masking unit between the transmission / reception unit and the header data extraction unit, and the reception data masking unit includes the transmission burst data. Receiving the output period explicit signal generated by the generating unit and the received burst data received by the transmitting / receiving unit, masking the output period explicit signal to the received burst data, and transmitting the transmission burst data transmitted from the own device. When receiving, the received burst data is not sent to the header / data extracting unit, which prevents erroneous operation due to the data transmitted by the own device, thereby solving the above-mentioned problem.

A ping-pong transmission device according to the present invention (claim 3) supplies a reception data buffer for storing data extracted from reception burst data by the header / data extraction unit, and data to be transmitted to the transmission burst data. A transmission data buffer for transmitting the signal of the high-speed serial bus, wherein the transmission data buffer and the reception data buffer are connected to a high-speed serial bus control unit and handle signals of the high-speed serial bus. .

[0016] A ping-pong transmission device according to the present invention (claim 4), wherein the header information indicates that transmission is terminated after transmission and a transmission right is given to another device (transmission end flag); The above problem is solved by including two flags, a flag (fixed length flag) indicating whether or not the burst data to be transmitted has a fixed length.

In each transmission, a flag (transmission end flag) indicating whether or not to end the transmission after the transmission and give the transmission right to the other device and a flag (fixed length flag) indicating whether the data to be transmitted has a fixed length. Is attached, and the following four types are notified to the receiving side by the combination of these two flags.

(A) The transmission data has a fixed length, and data communication is performed again after the data communication. (B) The transmission data has a fixed length, and after this data communication, the transmission right is given to the receiving side. (C) The transmission data has a variable length, and the data communication is performed again after the data communication. (D) The transmission data has a variable length, and after this data communication, the transmission right is given to the receiving side. In cases (C) and (D), a code (data end code) indicating the end of the transmission data is attached after the transmission data.

A ping-pong transmission method according to the present invention (claim 5) is a transmission / reception means for transmitting / receiving burst data comprising at least header information and data between at least two devices, and receiving / receiving data at the transmission / reception section. Header data extracting means for extracting header information and data from the burst data, and receiving the header data extracting means for judging the end of the reception period of the received burst signal from the extracted header information and data. At least end-determination means; and transmission-burst data generation means for generating transmission burst data by adding header information based on the data to be transmitted and transmitting the transmission burst data to the transmission / reception means. In response to the determination result of the end of the reception period determined by the determining means, the transmitting and receiving By transmitting to the device, it is possible ping-pong transmission, thereby solving the above problems.

A ping-pong transmission method according to the present invention (claim 6) includes a reception data masking means between the transmission / reception means and the header data extraction means, wherein the reception data masking means comprises the transmission burst data. Receiving the output period specifying signal generated by the generating unit and the received burst data received by the transmitting / receiving unit, masking the output period specifying signal on the received burst data, and transmitting the transmission burst data transmitted from the own device. When receiving, the received burst data is not sent to the header / data extracting means, which prevents malfunction due to the data transmitted by the own device, thereby solving the above-mentioned problem.

[0021] In a ping-pong transmission method according to the present invention (claim 7), a reception data buffer means for storing data extracted from reception burst data by the header data extraction means, and data to be transmitted to the transmission burst data, And a transmission data buffer means for supplying, the transmission data buffer and the reception data buffer,
The above problem is solved by being connected to high-speed serial bus control means and handling high-speed serial bus signals.

Hereinafter, the operation of the present invention will be described.

The receiving side receiving the (A) flag refrain from transmitting its own data, so that the transmitting side can restart the data transmission at an arbitrary timing.

The receiving side may receive fixed-length data following the header.

The receiving side receiving the (B) flag,
Data transmission can be started at any timing. The transmitting side shifts to the receiving state.

The receiving side may receive fixed-length data following the header.

The receiving side receiving the (C) flag refrain from transmitting its own data, so that the transmitting side can restart the data transmission at an arbitrary timing.

The receiving side may receive the data following the header up to the data end code.

The receiving side receiving the above (D) flag,
Data transmission can be started at any timing. The transmitting side shifts to the receiving state.

The receiving side may receive data following the header up to the data end code.

[0031]

(Embodiment 1) FIG. 1 is a block diagram showing a first embodiment of the present invention.

1 and 2 are ping-pong transmission devices. The internal configuration is the same for both, and details of the interior will be described later.

Reference numeral 3 denotes a transmission line for performing ping-pong transmission. Media such as electric wires, optical fibers, wireless, and infrared can be considered for the transmission path.

A transmission / reception unit 10 transmits transmission burst data 21 output from the transmission data generation unit 18 to the transmission line 3.
And transmits the received burst data 11 sent from the partner device to the header / data extracting unit 12 through the transmission path 3.

The transmission / reception unit 10 transmits the transmission burst data 21 and the reception burst data 11 according to the transmission path 3.
Is included in the function. That is, for example, when the transmission path is an optical fiber, it includes a function of performing conversion between an electric signal and an optical signal and performing modulation / demodulation. The same applies to the case where the transmission path 3 is another medium.

Reference numeral 11 denotes received burst data, which is output from the transmission / reception unit 10 and input to the header / data extraction unit 12.

Numeral 12 denotes a header / data extracting unit, which converts the received burst data 11 output from the transmitting / receiving unit 10 into
The header information 13 and the data 14 including the transmission end flag and the fixed length flag are extracted, the header information 13 is sent to the reception end determination unit 15, and the received data 14 is sent to the reception data buffer 15.
Is output to the reception end determination unit 16.

Reference numeral 13 denotes header information, which is output from the header / data extraction unit 12 and input to the reception end determination unit 15.

Numeral 14 denotes received data, which is output from the header / data extracting unit 12 and received by the reception data buffer 15.
Is input to the reception end determination unit 16.

Numeral 15 denotes a reception data buffer, which receives the reception data 14 output from the header / data extraction unit 12.
Is stored.

The output from the reception data buffer 15 is input to a location using data exchanged by ping-pong transmission.

Reference numeral 16 denotes a reception end determination unit which determines the end of reception from the header information 13 output from the header / data extraction unit 12 and the received data 14, and outputs a transmission start signal 17
Is output to the transmission data generation unit 20.

The determination of the end of reception differs depending on the values of the transmission end flag and the fixed length flag included in the header information 13.

FIG. 2 shows a flowchart of the processing in the reception end determining section 16 described above.

Step S1 is for waiting for input of header information 13 including a transmission end flag and a fixed length flag.

In step S2, it is determined whether a transmission end flag is set.

If the transmission end flag is not set, that is, if the partner device indicates that transmission is to be continued, it is necessary to output a transmission start signal because the own device needs to be continuously in the reception state. There is no. Therefore, the process ends. If the end flag is set, that is, if the partner device indicates that transmission ends after the transmission and shifts to the reception state, the process proceeds to step S3.

In step S3, it is determined whether or not the fixed length flag is set. If the fixed length flag is set,
That is, if the transmitted data indicates that the data has a fixed length, the process proceeds to step S4. If the fixed length flag is not set, that is, if it indicates that the transmitted data is variable length, the process proceeds to step S7.

In step S4, it is determined whether or not only a prescribed amount of fixed-length data has been received. If the specified amount of data has been received, it is determined that the reception has been completed, and step S6 is performed.
Move to

If the specified amount of data has not been received, the process proceeds to step S5.

Step S5 is for waiting for the next received data. After receiving the new data, the process moves to step S4.

In step S 6, since it is determined that the reception has been completed, the transmission start signal 17 is output to the transmission data generator 20.

In step S7, it is determined whether the variable length data has been received to the end. If the received data is a code indicating the end of data, it is determined that the data has been received to the end, and the process proceeds to step S6. If the received data is not a code indicating the end of data, the process proceeds to step S8.

Step S5 is for waiting for the next received data. After receiving the new data, the process moves to step S7.

Reference numeral 17 denotes a transmission start signal, which is output from the reception end determination section 12 and input to the transmission data generation section 20.

Reference numeral 18 denotes a transmission data buffer, which outputs data 19 to be transmitted to a transmission data generation unit 20.

The transmission data buffer 18 is inputted from a portion using data exchanged by ping-pong transmission.

Reference numeral 19 denotes data to be transmitted, which is output from the transmission data buffer 18 and input to the transmission data generator 20.

Reference numeral 20 denotes a transmission data generation unit. When a transmission start signal 17 output from the reception end determination unit 12 is input, it is determined whether data 19 to be transmitted needs to be transmitted following the transmission. The transmission burst data 21 is added to the transmission data, and the transmission burst data 21 is added to the transmission data by adding a fixed length flag to the transmission data according to whether the transmission data has a fixed length. Output to

As a method of adding the transmission end flag and the fixed length flag, each may be added as a flag bit to the head of the transmission data, or a code representing each of the four states formed by combining the two flags may be added to the head. The data 19 to be transmitted may include a code indicating any one of the four states.

Reference numeral 21 denotes transmission burst data, which is output from the transmission data generation unit 20 and input to the transmission / reception unit 10.

FIG. 3 shows the ping-pong transmission according to the first embodiment of the present invention.

For the sake of convenience, in this figure, when the transmission end flag and the fixed length flag are set, "1" is written, when they are not set, "0" is written, and the data end code is written "E". I have.

In this figure, the time delay in the transmission path 3 is omitted.

As shown in FIG. 3, when the transmission end flag added to the data is set, the transmission side and the reception side are switched after the end of the transmission. When the transmission end flag is not set, the transmission end flag is set. After the transmission is completed, the transmitting side continues the transmission.

When the fixed length flag is set,
The data to be transmitted is fixed length, and if the fixed length flag is not set, the data to be transmitted is variable length,
Ends with data end code.

In the above description, the transmission data is transmitted from the transmission side to the reception side by a combination of two flags, a transmission end flag and a fixed length flag. I do. (B) The transmission data has a fixed length, and after this data communication, the transmission right is given to the receiving side. (C) The transmission data has a variable length, and the data communication is performed again after the data communication. (D) This transmission data has a variable length, and after transmitting this data, the transmission right is transferred to the receiving side. (B) and (C)
May be used alone.

(Embodiment 2) FIG. 4 is a block diagram showing a second embodiment of the present invention.

In FIG. 4, the transmitting / receiving unit 10, header information 1
3, the received data 14, the received data buffer 15, the reception end determination unit 16, the transmission start signal 17, the transmission data buffer 18, the data 19 to be transmitted, and the transmission burst data 21 are the same as those in the first embodiment. is there.

Reference numeral 11 denotes received burst data, which is output from the transmitting unit 10 and input to the received data masking unit 23.

Reference numeral 12 denotes a header / data extracting unit that extracts header information 13 and data 14 including a transmission end flag and a fixed length flag from the masked reception burst data 24 output from the reception data masking unit 23. The header information 13 is output to the reception end determination unit 15, and the received data 14 is output to the reception data buffer 15 and the reception end determination unit 16.

Reference numeral 20 denotes a transmission data generation unit. When a transmission start signal 17 output from the reception end determination unit 12 is input, it is determined whether data 19 to be transmitted needs to be transmitted following the transmission. The transmission burst data 21 is added to the transmission data, and the transmission burst data 21 is added to the transmission data by adding a fixed length flag to the transmission data according to whether the transmission data has a fixed length. Output to

When transmitting the transmission burst data 21 to the input / output unit 10, the reception data masking unit 23 outputs a signal indicating that the own device is currently outputting the signal and an output period specifying signal 22.
Output to

The method of adding the transmission end flag and the fixed length flag is the same as in the first embodiment.

Reference numeral 22 denotes an output period explicit signal, which is output from the transmission data generation unit 20 and input to the reception data masking unit 23.

Reference numeral 23 denotes a reception data mask unit which converts the reception burst data 11 output from the transmission / reception unit 10 into the transmission period specifying signal 23 output from the transmission data generation unit 20.
, And outputs the masked reception burst data 24 to the header data extraction unit 12.

This processing prevents the transmission burst data 21 input to the transmission / reception section 10 from being erroneously operated by the data transmitted by itself when the transmission burst data 21 is configured to be output as the reception burst data 11.

Reference numeral 24 denotes masked reception burst data, which is output from the reception data masking unit 23 and has a header
The data is input to the data extraction unit 12.

With the above-described configuration, in addition to the case of the first embodiment, malfunction can be prevented even when data transmitted by the own device is received as received data.

(Embodiment 3) FIG. 5 is a block diagram showing a third embodiment of the present invention.

Reference numerals 1 and 2 denote ping-pong transmission devices described in the first embodiment or the second embodiment. The reception data buffer 15, the transmission data buffer 18, and the transmission / reception unit 10, Receive burst data 11,
A header / data extraction unit 12, header information 13, received data 14, reception end determination unit 16, transmission start signal 17,
The data 19 to be transmitted, the transmission burst data generation unit 20, the transmission burst data 21, the reception burst data masking unit 22, the transmission period specifying signal 23, and the masked burst signal 24 are described in the first embodiment or the second embodiment. This is the same as the embodiment.

Reference numeral 25 denotes a reception IEEE 1394 bus signal code, which is output from the reception data buffer 15 and is
It is input to the EE1394 bus control unit 26.

Reference numeral 26 denotes an IEEE 1394 bus control unit, which receives the received IEEE 1394 bus from the reception buffer 15.
Interprets the 94 bus signal code 25 and transmits the transmission IEEE 139
4 bus signal code 27, and determines the transmission data buffer 1
8 is output.

Although this embodiment has only one input means and one output means for the IEEE 1394 bus signal code to the IEEE 1394 bus control unit 26, input from a plurality of receive data buffers or another IEEE 1394 bus signal code is required.
394 bus signal input means, and outputs to a plurality of transmission data buffers or another IEEE 1394 bus signal output means, interprets the inputs from the plurality of IEEE 1394 bus signal input means, and interprets the plurality of IEEE 1394 bus signal input means.
The signal may be output from the 1394 bus signal output means.

In this embodiment, the IEEE 1394 bus controller 26 is described as being inside the ping-pong transmission device, but it may be in another device. Again, I
EEE1394 bus control unit 26 and reception data buffer 1
5 and the transmission data buffer 18 need to be connected by some means.

Reference numeral 27 denotes a transmission IEEE 1394 bus signal code, which is output from the IEEE 1394 bus control unit 26 and input to the transmission data buffer 18.

Received IEEE 1394 bus signal code 25
And the transmission IEEE 1394 bus signal code 27 is 4
Using an encoding called B5B or 8B10B,
This is a code that encodes the state of the bus and the data transmitted and received using the bus.

[0088]

As described above, according to the present invention (claims 1, 2, 3, 4, 5, 6, and 7), the amount of data that can be transmitted in one burst without assuming a master-slave relationship. Can be provided.

Further, in particular, according to the present invention (claims 2 and 6), it is possible to prevent a malfunction by receiving data transmitted by the own device.

[Brief description of the drawings]

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

FIG. 2 is a flowchart of a process of a reception end determination unit according to the present invention.

FIG. 3 is an explanatory diagram showing transmission / reception switching using a transmission end flag and a fixed length flag according to the present invention.

FIG. 4 is a block diagram of a second embodiment of the present invention.

FIG. 5 is a block diagram of a third embodiment of the present invention.

FIG. 6 is an explanatory diagram showing a conventional ping-pong transmission method for performing transmission and reception by time division.

FIG. 7 is an explanatory diagram showing transmission / reception switching using a conventional flag bit.

FIG. 8 is an explanatory diagram showing a case where a conventional training period is provided.

DESCRIPTION OF THE SYMBOLS 1, 2 Ping-pong transmission equipment according to the embodiment of the present invention 3 Transmission line for performing ping-pong transmission 10 Transmitter / receiver 11 Received burst data 12 Header / data extractor 13 Header information 14 Received data 15 Reception data buffer 16 reception end determination unit 17 transmission start signal 18 transmission data buffer 19 data to be transmitted 20 transmission data generation unit 21 transmission burst data 22 reception data masking unit 23 transmission period explicit signal 24 masked reception burst data 25 reception IEEE 1394 bus signal code 26 IEEE 1394 bus control unit 27 Transmission IEEE 1394 bus signal code

Claims (7)

[Claims] 1. A transmission / reception unit for transmitting and receiving burst data including at least header information and data between at least two devices, and extracting header information and data from received burst data received by the transmission / reception unit. A header / data extracting unit that performs a receiving end determining unit that determines the end of the receiving period of the received burst signal from the header information and the data extracted by the header / data extracting unit; and a header based on the data to be transmitted. At least a transmission burst data generation unit for generating transmission burst data by adding information and transmitting the transmission burst data to the transmission / reception unit; and a determination result of a reception period end determined by the reception end determination unit. Receiving, from the transmitting / receiving unit, transmitting transmission burst data to another device, thereby enabling ping-pong transmission. Ping-pong transmission equipment that. 2. A reception data masking unit is provided between the transmission / reception unit and the header data extraction unit, wherein the reception data masking unit outputs an output period specifying signal generated by the transmission burst data generation unit, Upon receiving the reception burst data received by the transmission / reception unit, masking the output period explicit signal on the reception burst data, and receiving the transmission burst data transmitted from the own device, the reception burst data is converted into header data. 2. The ping-pong transmission device according to claim 1, wherein the ping-pong transmission device does not send the data to the extraction unit, and prevents malfunction due to data transmitted by the device. 3. A transmission data buffer for storing data extracted from the reception burst data by the header data extraction unit, and a transmission data buffer for supplying data to be transmitted to the transmission burst data. 3. The ping-pong transmission device according to claim 1, wherein the buffer and the reception data buffer are connected to a high-speed serial bus control unit and handle signals of the high-speed serial bus. 4. The header information indicates a flag (transmission end flag) indicating whether to end transmission after transmission and transfer the transmission right to another device, and whether the burst data to be transmitted has a fixed length. 4. The ping-pong transmission device according to claim 1, further comprising two flags: a flag (fixed-length flag). 5. A transmitting / receiving means for transmitting and receiving burst data comprising at least header information and data between at least two devices, and extracting header information and data from the received burst data received by said transmitting / receiving unit. Header data extraction means for performing, a reception end determination means for determining the end of the reception period of the reception burst signal from the header information and data extracted by the header data extraction means, and a header based on the data to be transmitted. At least transmission burst data generation means for generating transmission burst data by adding information, and transmitting the transmission burst data to the transmission / reception means, wherein the reception end determination result determined by the reception end determination means is determined. Ping-pong transmission by transmitting the transmission burst data from the transmission / reception means to another device. Ping-pong transmission and wherein the such. 6. A receiving data masking means between said transmitting / receiving means and said header data extracting means, said receiving data masking means comprising: an output period specifying signal generated by said transmission burst data generating means; Receiving the received burst data received by the transmission / reception means, masking the output period explicit signal to the received burst data, and when receiving the transmitted burst data transmitted from the own device, the received burst data is converted into header data. 6. The ping-pong transmission method according to claim 5, wherein the ping-pong transmission method does not send the data to the extracting means, and prevents a malfunction from occurring due to data transmitted from the own device. 7. A receiving data buffer means for storing data extracted from received burst data by the header / data extracting means, and a transmitting data buffer means for supplying data to be transmitted to the transmitting burst data. 7. The ping-pong transmission method according to claim 5, wherein the transmission data buffer and the reception data buffer are connected to high-speed serial bus control means and handle high-speed serial bus signals.