JP2006086884A - Transmission path repeater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transmission path repeater which suppresses decrease of throughput even when repeating to a transmission path with lower transmission rate. <P>SOLUTION: A first transmission path received data compression part 121 converts received data into a corresponding management data identifier if the received data is OOB to the received data from a first transmission path 2, converts the received data into a corresponding management data identifier if the received data is Primitive, performs 10b/8b conversion if the received data is actual data to be transmitted, accumulates the received data in a first transmission path received data buffer 122 and a second transmission path transmitting data generation part 12 arranges pieces of the same kind of data which are continuously received in one packet from the data in the first transmission path received data buffer 122, generates a packet to which a flag for identifying management data and the actual data is added and transmits the packet from a transmitting packet buffer 13 by a second transmission path transmitting part 14. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a transmission path relay device that relays transmission data between different transmission paths.

  Conventionally, a transmission apparatus that transmits data stored in a DVD (Digital Versatile Disk) medium or the like is known, and such a transmission apparatus transmits data read from the medium as shown in FIG. Device 210, transmission path 220 for transmitting data between transmission device 210 and reception device 230, reception device 230 for decoding and outputting data received from transmission device 210, and data output by reception device 230 And a display device 240 for displaying. (For example, refer to Patent Document 1).

  The transmission device 210 packetizes the drive device 211 that reads data from a DVD medium and the like, the stream data read by the drive device 211 and the command output from the drive device 211, and passes through the transmission path 220. A first packet processing unit 212 that outputs a command corresponding to the transmitted packet to the drive device 211, a packet created by the first packet processing unit 212 is output to the transmission path 220, and a packet is transmitted from the transmission path 220. A first transmission path interface section 213 that receives and outputs the first packet processing section 212 to the first packet processing section 212 and a first stream data transmission path 214 that transmits data between the first packet processing section 212 and the drive device 211 are provided.

  The receiving device 230 packetizes the decoding unit 231 that decodes the compressed data recorded on the DVD medium or the like, and the command output from the decoding unit 231 and transmits the packet via the transmission path 220. The second packet processing unit 232 that recognizes the received packet and outputs it to the decoding unit 231 as stream data or a command, and outputs the packet created by the second packet processing unit 232 to the transmission path 220 and from the transmission path 220 A second transmission path interface unit 233 that receives a packet and outputs the packet to the second packet processing unit 232; and a second stream data transmission path 234 that transmits data between the second packet processing unit 232 and the decoding unit 231. ing.

  Note that the first packet processing unit 212 and the second packet processing unit 232 each include a buffer 212a and a buffer 232a that are used when data is transmitted and received.

  In such a transmission apparatus, the stream data and commands packetized by the first packet processing unit 212 are multiplexed and transmitted from the first transmission path interface unit 213 using a synchronization channel.

  Further, when the second packet processing unit 232 packetizes the command output from the decoding unit 231, the flow control information output from the decoding unit 231 is multiplexed and packetized, and the synchronization channel of the transmission path 220 is set. The data is transmitted to the first packet processing unit 212, and reading / writing with respect to the drive device 211 is controlled based on the flow control information.

Here, the first packet processing unit 212 and the first transmission path interface unit 213 function as a transmission path relay device that relays between the transmission path 220 and the first stream data transmission path 214, and the second packet processing section 232 and the first transmission path interface section 213. The two transmission path interface unit 233 functions as a transmission path relay device that relays between the transmission path 220 and the second stream data transmission path 234.
JP 2003-198559 A

  However, in the conventional transmission apparatus, since the stream data and the command are packetized and multiplexed and transmitted on the transmission path 220, the total transmission speed of the stream data and the command cannot exceed the maximum transmission speed of the transmission path 220. It was.

  The throughput of the transmission path 220 is calculated from the throughput of the first stream data transmission path 214 by the ratio between the maximum transmission speed of the first stream data transmission path 214 and the maximum transmission speed of the transmission path 220. When the throughput of the data transmission path 214 is small and the maximum transmission speed of the first stream data transmission path 214 is significantly faster than the maximum transmission speed of the transmission path 220, there is a problem that the throughput of the transmission path 220 becomes small.

  Here, the throughput represents the transmission speed of the data body to be transmitted, and does not include additional data depending on the transmission method such as transmission management data, flow control signal, and error correction data. The data body to be transmitted is hereinafter referred to as transmission data.

  The present invention has been made to solve the conventional problems, and an object of the present invention is to provide a transmission line relay device capable of suppressing a reduction in throughput even when relaying to a transmission line with a lower transmission speed. To do.

  The transmission line relay apparatus according to the present invention relays a first transmission line that transmits the actual data to be transmitted and transmission management data separately, and a second transmission line that has a lower transmission speed than the first transmission line. A first transmission path receiving means for receiving data from the first transmission path; and first transmission path reception data for compressing at least the management data of the data received by the first transmission path receiving means. A compression unit; and a second transmission line transmission unit that transmits the data processed by the first transmission line reception data compression unit to the second transmission line.

  With this configuration, at least management data among data received from the first transmission path is compressed and transmitted to the second transmission path, and a decrease in throughput can be suppressed.

  Here, a flag for identifying whether the data to be transmitted is the actual data or the management data is added from the actual data and the management data processed by the first transmission path reception data compression unit, and the continuous data A second transmission path transmission data generating means for generating a packet so that actual data or management data is combined into one packet; the second transmission path transmitting means is a packet generated by the second transmission path transmission data generating means; Is configured to transmit to the second transmission path.

  With this configuration, the same type of continuous data is collected and transmitted as one packet. Therefore, the compression rate of data transmitted to the second transmission path can be increased.

  Further, the first transmission line is a serial transmission line, and the first transmission line reception data compression means converts the real data converted from 8-bit data received from the first transmission line into 10-bit data by 10 bits. The data is converted into 8-bit data.

  With this configuration, actual data received from the first transmission path is also compressed, and a reduction in throughput can be suppressed.

  Further, the first transmission line receiving means receives an OOB signal for transmitting a message according to a waveform pattern, and the second transmission line transmission data generating means is an OOB signal in which the flag is set in the management data from the OOB signal. The packet which shows is produced.

  With this configuration, the OOB signal can be transmitted between the first transmission path and the second transmission path.

  Further, the first transmission path is serial ATA, and the first transmission path reception data compression unit is configured to delete all primitives received from the first transmission path.

  With this configuration, primitives received from the first transmission path are not transmitted to the second transmission path, and a decrease in throughput can be suppressed.

  Further, the first transmission line is a serial ATA, and the first transmission line reception data compression means deletes a predetermined number of primitives when receiving the same kind of primitives continuously from the first transmission line. The configuration.

  With this configuration, consecutive primitives of the same type received from the first transmission path are deleted leaving a part, and useless primitives are not transmitted to the second transmission path. Therefore, a decrease in throughput can be suppressed.

  Further, the first transmission line is serial ATA, and the first transmission line reception data compression unit deletes all the received primitives according to the type of primitive received from the first transmission line, or A configuration is adopted in which a predetermined number of consecutive primitives of the same type are deleted or deleted.

  With this configuration, only the minimum necessary primitives are transmitted to the second transmission path. Therefore, a decrease in throughput can be suppressed.

  Further, the first transmission path received data compression means is configured to replace the primitive that has not been deleted among the primitives received from the first transmission path with an identifier having a smaller data amount than the primitive.

  With this configuration, the primitive is replaced with an identifier having a small amount of data. Therefore, the compression rate of data transmitted to the second transmission path can be increased.

  Further, the first transmission path received data compression means converts the primitives not deleted from the primitives received from the first transmission path from 10 bits to 8 bits and transmits the lower 3 bytes of the conversion result. It was set as the data used.

  With this configuration, the amount of primitive data can be reduced, and the compression rate of data transmitted to the second transmission path can be increased.

  The first transmission path receiving means determines whether the data received from the first transmission path needs a response immediately. If it is determined that a response is required immediately, a response corresponding to the data is transmitted to the first transmission path. It was configured to transmit to the road.

  With this configuration, when data that requires a response immediately is received from the first transmission path, the response is transmitted immediately, and relaying can be performed while maintaining the transmission specifications of the first transmission path.

  Further, the first transmission line is a serial ATA, and the first transmission line receiving means transmits an ALIGN from the host to the device in a serial ATA initialization sequence from transmission / reception between the COMWAKE device and the host. The configuration is such that it is determined that a response is required immediately for the data received until then.

  With this configuration, relaying can be performed while satisfying the conditions of the initialization processing sequence in serial ATA.

  Further, the first transmission path is a serial ATA, and the first transmission path receiving means determines that a response is required immediately upon receiving the HOLD primitive of the serial ATA.

  With this configuration, the speed of response to flow control in serial ATA can be increased.

  A reception packet buffer for temporarily storing data received from the second transmission path; and first transmission path transmission data generation for generating data to be transmitted to the first transmission path when the reception packet buffer is empty. Means.

  With this configuration, data can always be transmitted to the first transmission path.

  Furthermore, the first transmission path transmission data generating means generates data to be transmitted to the first transmission path based on data transmitted to the first transmission path last time.

  With this configuration, data can always be transmitted to the first transmission path.

  A receiving packet buffer for temporarily storing packets received from the second transmission path; and a transmission packet buffer for temporarily storing packets to be transmitted to the second transmission path. When a reset request is received from any one of the second transmission paths, both the reception packet buffer and the transmission packet buffer are emptied.

  With this configuration, it is possible to delete data already stored in the buffer in response to a sudden initialization process during the relay process, and to prevent the initialization sequence from being disturbed by such data. .

  In addition, when the second transmission path is in a communication disabled state, there is provided a returning means for returning the second transmission path to a communication enabled state.

  With this configuration, even when the second transmission path is in a communication disabled state, it can be returned to a communication enabled state.

  Moreover, it was set as the structure which performs flow control independently by said 1st transmission path and said 2nd transmission path.

  With this configuration, it is possible to prevent overflow of received data when relaying to a transmission path with a lower transmission speed.

  The first transmission path receiving means includes transmission path identifier adding means for receiving data from a plurality of transmission paths and adding a transmission path identifier capable of distinguishing the plurality of transmission paths. The data compression means compresses the data from the plurality of transmission paths received by the first transmission path reception means, and adds the transmission path identifier to the data processed by the first transmission path reception data compression means. The data is transmitted to the second transmission path.

  With this configuration, even when there are a plurality of transmission lines, transmission can be performed on the second transmission line having a low transmission rate while suppressing a decrease in throughput in a form that distinguishes them.

  According to the present invention, by compressing at least management data of data received from the first transmission path, it is possible to suppress a decrease in throughput even when relaying to a transmission path having a lower transmission speed.

  Hereinafter, a transmission line relay device according to an embodiment of the present invention will be described with reference to the drawings.

  A transmission line relay apparatus according to an embodiment of the present invention is shown in FIG.

  In FIG. 1, a transmission line relay device 1 is connected to a reception signal line 21 of a first transmission line 2 conforming to a serial ATA (SATA, Serial AT Attachment) standard and receives data from the reception signal line 21. The receiving unit 11, the second transmission line transmission data generation unit 12 that acquires the data received by the first transmission line reception unit 11, packetizes and outputs the data, and the packet output by the second transmission line transmission data generation unit 12 The transmission packet buffer 13 for temporarily storing and the transmission signal line 32 of the second transmission path 3 in accordance with the MOST (Media Oriented System Transport) standard are connected to acquire a transmission packet from the transmission packet buffer 13 and transmit it to the transmission signal line 32. A second transmission path transmitter 14 that is connected to the reception signal line 31 of the second transmission path 3 and receives the data from the reception signal line 31; A reception packet buffer 16 that temporarily stores data received by the transmission path receiving unit 15, and a first transmission path transmission data generation unit 17 that acquires data from the reception packet buffer 16 and generates data to be transmitted to the first transmission path 2. And a first transmission path transmission section 18 connected to the transmission signal line 22 of the first transmission path 2 and transmitting the data generated by the first transmission path transmission data generation section 17 to the transmission signal line 22.

  The second transmission line transmission data generating unit 12 includes a first transmission line reception data compression unit 121 that outputs unnecessary data from the data received by the first transmission line reception unit 11 and first transmission line reception data. A first transmission path reception data buffer 122 for temporarily storing data output from the compression unit 121;

  The first transmission line transmission data generation unit 17 includes a first transmission line transmission data return unit 171 that generates data to be transmitted to the first transmission line from a packet acquired from the reception packet buffer 16, and a first transmission line transmission data recovery unit. 171 includes a first transmission path transmission data buffer 172 for temporarily storing data generated by 171.

  The first transmission path receiving unit 11 receives a message having a waveform pattern called OOB (Out Of Band) in serial ATA separately from digital data transmission by normal differential transmission.

  The first transmission line reception unit 11 includes a physical layer and a link layer of serial ATA, and the OOB is received by the physical layer of serial ATA. The data other than OOB is received as digital data according to normal transmission of serial ATA.

  The first transmission path 2 is not limited to the one according to the serial ATA standard. If the maximum transmission speed exceeds the transmission speed of the second transmission path 3, the ATAPI (AT Attachment Packet Interface) standard is used. Or a transmission line according to the above.

  The first transmission path receiving unit 11 is not limited to OOB or differential transmission as long as the first transmission path 2 is other than serial ATA, and may support other digital / non-digital data transmission schemes. The message transmission method using the waveform pattern is not limited to serial ATA OOB, but may be, for example, a method of detecting USB (Universal Serial Bus) chirp.

  The second transmission path transmission data generation unit 12 acquires data from the first transmission path reception unit 11 and deletes unnecessary data in the first transmission path reception data compression unit 121 while the first transmission path reception data buffer 122. To accumulate. The OOB is acquired as an OOB-specific message, and data other than the OOB is acquired from the first transmission path receiving unit 11 in units of Dword (10 bits × 4 40 bits) when data is handled in the link layer of the serial ATA.

  The second transmission path transmission data generation unit 12 refers to the data amount stored in the first transmission path reception data buffer 122 and the data received from the first transmission path reception unit 11, and satisfies the packet generation conditions described later. In this case, the data stored in the first transmission path reception data buffer 122 is packetized and moved to the transmission packet buffer 13.

  The second transmission path transmission unit 14 acquires the transmission packet from the transmission packet buffer 13 at the transmission timing of the second transmission path 3 and transmits it to the second transmission path 3. If the transmission packet buffer 13 is empty, only 0 is transmitted to the second transmission path 3.

  Note that the second transmission line transmission unit 14 supports flow control and priority transmission mode, which will be described later, and when a packet whose priority transmission mode is 1 is at the head of the transmission packet buffer 13, the flow control is performed. Even if transmission to the second transmission path 3 is stopped, all packets whose priority transmission mode is 1 are transmitted from the top of the transmission packet buffer 13.

  Data from the second transmission path 3 is received from the reception signal line 31 to the second transmission path receiver 15 and stored in the reception packet buffer 16.

  The first transmission line transmission data generation unit 17 acquires a packet from the reception packet buffer 16, generates data to be transmitted to the first transmission line by the first transmission line transmission data return unit 171, and transmits the first transmission line transmission data buffer. 172.

  The first transmission path transmission unit 18 acquires data from the first transmission path transmission data buffer 172 and flows the data to the transmission signal line 22 of the first transmission path 2.

  The second transmission path 3 is not limited to the one according to the MOST standard, and the transmission speed thereof is smaller than that of the first transmission path 2, and is the IEEE (the Institute of Electrical and Electronic Engineers) 1394 standard. It may be a device that conforms to the USB standard or a wireless local area network (LAN).

  FIG. 2 is an example of a transmission apparatus that uses such a transmission line relay apparatus 1.

  As shown in FIG. 2, the transmission apparatus includes a drive device 4 that reads data from a DVD medium, a first transmission path 2a and a third transmission path 2b that conform to the serial ATA standard (the first transmission path 2 in FIG. 1). 1), a second transmission line 3a (corresponding to the second transmission line 3 in FIG. 1) according to the MOST standard, and a first transmission line 2a that relays between the first transmission line 2a and the second transmission line 3a. The transmission line relay apparatus 1a, the second transmission path relay apparatus 1b that relays between the second transmission path 3a and the third transmission path 2b, and the DVD-Video data recorded on the DVD medium are decoded. The decoding unit 5 includes a CRT (Cathode Ray Tube) for displaying data decoded by the decoding unit 5 and a display device 6 such as liquid crystal or plasma.

  The first transmission line relay device 1a and the second transmission line relay device 1b have the configuration shown in FIG. 1, but the second transmission line 3a and the second transmission line transmission unit 14 are connected to the second transmission line 3a. Since the path receiving unit 15 is connected, a packet transmitted from the second transmission path transmitting unit 14 of the first transmission path relay apparatus 1a passes through the second transmission path 3a and is transmitted to the second transmission path relay apparatus. The packet received by the second transmission line receiver 15 of 1b and transmitted from the second transmission line transmitter 14 of the second transmission line relay device 1b is transmitted through the second transmission line 3a to the first transmission. It is received by the second transmission path receiving unit 15 of the path relay device 1a.

  The drive device 4 is not limited to a device that reads data from a DVD medium, and may be a device that reads data from a CD (Compact Disc) or reads data from a hard disk. Corresponding to this, the decrypting unit 5 connects what can decrypt the data read by the drive device 4.

  The first transmission path 2a and the third transmission path 2b are not limited to those according to the serial ATA standard, and the maximum transmission speed exceeds the transmission speed of the second transmission path 3a. If there is, a transmission line according to the ATAPI (AT Attachment Packet Interface) standard may be used.

  The second transmission path 3a is not limited to the one according to the MOST standard, and the transmission speed is lower than that of the first transmission path 2a or the third transmission path 2b. An Institute of Electrical and Electronic Engineers (1394) standard, a USB (Universal Serial Bus) standard, or a wireless local area network (LAN) may be used.

  Further, the decryption unit 5 and the drive device 4 correspond to serial ATA standard hosts and devices, respectively.

  Further, the second transmission path 3a transmits DVD-Video data and reproduces it without interruption in the display device 6 as in this embodiment, and the 11. transmission necessary for DVD-Video. In addition to 08 Mbps, a bandwidth of several Mbps is required for transmission management data. Of course there may be more.

  3 and 4 are flowcharts for explaining the processing of the second transmission path transmission data generation unit 12.

  As illustrated in FIG. 3, the second transmission path transmission data generation unit 12 first acquires data received by the first transmission path reception unit 11 from the first transmission path 2 (S11).

  Next, priority transmission mode determination is performed based on the acquired data (S12). For example, it is determined whether the acquired data is data to be transmitted with priority over other data such as a reset command using serial ATA OOB transmission. If the data is to be transmitted with priority (TRUE), the priority transmission is performed. The mode is turned on (S13), and if it is not data to be transmitted with priority (FALSE), the priority transmission mode is turned off (S14). In the priority mode determination of the present embodiment, the priority transmission mode is turned on when the received data is data transmitted using OOB transmission. Note that the priority transmission mode may be turned on in the case of DMATP primitive (DMAT primitive).

  Then, it is determined whether or not the data accumulated in the first transmission path reception data buffer 122 is packetized and moved to the transmission packet buffer 13 (S15).

The determination condition is OR of the following three conditions.
Condition 1: The first transmission path reception data buffer 122 is full.
Condition 2: The data type stored in the first transmission path reception data buffer 122 is different from the data type of the data received this time.
Condition 3: The priority transmission mode is on.

  There are two types of data types of condition 2, real data to be transmitted and management data for transmission.

  When any one of the conditions 1 to 3 is satisfied (TRUE), the data stored in the first transmission path reception data buffer 122 is packetized and moved to the end of the transmission packet buffer 13 (S16).

  By doing in this way, the continuous same kind of data can be collectively transmitted in one packet.

  FIG. 5 is a diagram showing a packet format used in the second transmission path 3a.

  The packet is composed of a header part and a data part. The header part includes a preamble, a data part data length, a priority transmission mode, and a type.

  The preamble represents the beginning of the packet, and the beginning of the packet can be recognized by detecting the preamble from a state in which data is continuous 0, and reception of the packet can be started.

  In the priority transmission mode, the determination result of the priority transmission mode determination (S12) of the second transmission path transmission data generation unit 12 is reflected.

  The type is synonymous with the data type of condition 2 and is a bit that identifies whether the data is actual data or management data. If the type is 0, it indicates that actual data is stored in the data part, and if the type is 1, it indicates that management data is stored in the data part. As the management data, a management data identifier corresponding to a primitive (primitive) for controlling transmission / reception and communication of frames with the serial ATA OOB is set. FIG. 6 is a correspondence table of OOB and Primitive and management data identifier.

  Note that the transmission method of OOB and Primitive may be 8 bits or more. As for the Primitive transmission method, only the lower 3 Bytes of Primitive, which is a 4-byte unit, may be transmitted. Further, a Dword unit (4 × 10 bits) may be used.

  The packet format is not limited to that shown in FIG. 5, and may be a fixed-length packet, for example, as long as at least actual data and management data can be distinguished and transmitted.

  In the present embodiment, the actual data and the management data are distinguished by the packet header. However, the present invention is not limited to this, and the bandwidth of the actual data and the management data is set on the second transmission path 3a. Each may be provided separately for transmission.

  Next, initialization-related process activation determination described later is performed (S17), and when the condition is satisfied (TRUE), initialization-related process is performed (S18).

  Next, moving to FIG. 4, the received data is compressed by the first transmission path received data compression unit 121.

  The first transmission path reception data compression unit 121 determines whether or not transmission is possible for the received data (S19). If it is not in the initialization mode, it is always transmitted when the received data is actual data. When Primitive of serial ATA is received, processing is changed according to the type of Primitive as shown in FIG.

  In FIG. 7, “◯” indicates that all are transmitted, “Δ” indicates that only one is transmitted when the same Primitive is continuous, and “×” indicates that all are not transmitted.

  The conditions during the initialization mode will be described later. Since OOB is always in the initialization mode at the time of determining whether transmission is possible, it will be described later.

  As a result of the transmission permission / inhibition determination, when transmitting (TRUE), it is determined whether the received data is OOB (S20). If the received data is OOB, the OOB is converted into a management data identifier according to the correspondence table of FIG. (S21).

  If the received data is not OOB, it is determined whether the received data is Primitive (S22). If the received data is Primitive, Primitive is converted into a management data identifier according to the correspondence table of FIG. 6 (S23).

  If the received data is not Primitive, it is determined whether the received data is actual data to be transmitted (S24). If the received data is actual data to be transmitted, it is generally used in a high-speed serial interface such as serial ATA. The 10b / 8b conversion that is the inverse of the 8b / 10b conversion that is the encoding method is performed (S25).

  The data converted into 8 bits by the method corresponding to the received data by the above process is stored at the end of the first transmission path received data buffer 122 (S26).

  In this way, the first transmission path received data compression unit 121 compresses the data received from the first transmission path.

  Next, the priority transmission mode is determined (S27). If the priority transmission mode is on, the contents of the first transmission path reception data buffer 122 are packetized and stored at the head of the transmission packet buffer 13 (S28).

  If the priority transmission mode is off, packet generation determination is performed based on the accumulation status of the first transmission path reception data buffer 122 and the transmission packet buffer 13 (S29).

  If the first transmission path reception data buffer 122 is not empty and the transmission packet buffer 13 is not empty (TRUE), the contents of the first transmission path reception data buffer 122 are packetized and stored at the end of the transmission packet buffer 13 ( S30).

  8 and 9 are flowcharts for explaining the processing of the first transmission path transmission data generation unit 17. The processing of the first transmission line transmission data generation unit 17 is performed using a request from the first transmission line transmission unit 18 as a trigger.

  As shown in FIG. 8, first, it is determined whether or not the priority transmission mode of the first packet in the reception packet buffer 16 is 1 (ON) (S51), and the priority transmission mode is 1 from the reception packet buffer 16 to the rear. Process all packets.

  For the packet whose priority transmission mode is 1, the first transmission line transmission data restoration unit 171 performs processing for restoring the data in the data part of the packet to the data to be transmitted to the first transmission line 2 as shown in FIG. (S52).

  Moving to FIG. 9, initialization-related process activation determination described later is performed (S101). If the condition is satisfied (TRUE), initialization-related process is performed (S102).

  Next, it is determined whether the type of the data part of the packet is a management data identifier and this management data identifier is OOB according to the correspondence table of FIG. 6 (S103). If it is OOB, this management data identifier is assigned to the correspondence table of FIG. To OOB (S104).

  If the data part is other than OOB, it is determined whether the type of the data part is a management data identifier and this management data identifier is Primitive according to the correspondence table of FIG. 6 (S105). If the data part is Primitive, this management part The data identifier is converted into Primitive according to the correspondence table of FIG. 6 (S106).

  If the data part is not Primitive, it is determined whether the data part is actual data transmitted (S107). If the data part is actual data transmitted, 8b / 10b conversion is performed (S108).

  Note that the creation of Primitive or the 8b / 10b conversion is performed in consideration of the Running Disparity of the serial ATA.

  By such processing, 1D word (4 × 10 bits) serial ATA transmission data is created.

  Next, returning to FIG. 8, it is determined whether the data portion of the received packet is a management data identifier corresponding to OOB (S53). If it is OOB, an OOB transmission instruction is sent to the first transmission line transmission portion 18 ( S55) Since the buffer is cleared in the initialization-related process, the process of the first transmission path transmission data generation unit 17 is terminated.

  If it is not OOB, the created 1 Dword data is stored at the end of the first transmission path transmission data buffer 172 (S54), the process returns to S51, and the priority packet transmission mode of the first packet of the reception packet buffer 16 is 1. The processes from S52 to S54 are repeated.

  In S51, if the priority transmission mode of the first packet in the reception packet buffer 16 is 0, it is determined whether the first transmission path transmission data buffer 172 is empty (S56), and the first transmission path transmission data buffer 172 must be empty. For example, data is acquired from the head of the first transmission path transmission data buffer 172 (S57), and the acquired transmission data is passed to the first transmission path transmission unit 18 (S58).

  If the first transmission path transmission data buffer 172 is empty, it is determined whether the reception packet buffer 16 is empty (S59). If the reception packet buffer 16 is not empty, the data portion of the first packet in the reception packet buffer 16 is determined. It is determined whether all conversion processing has been performed (S60), and processing is performed for all data portions.

  The first transmission path transmission data restoration unit 171 performs the processing by the packet data portion shown in FIG. 9 on the data portion of the first packet as in S52 (S61).

  The 1D word data created by this process is stored at the end of the first transmission path transmission data buffer 172 (S62), and the process returns to S60, and the processes of S61 and S62 are performed for the data length of the data part of the packet. Is processed from the head of the first transmission path transmission data buffer 172 (S57), and the acquired transmission data is passed to the first transmission path transmission section 18 (S58).

  Next, if the reception packet buffer 16 is empty in S59, data to be transmitted this time is generated from the previous transmission data (S63). If the previous transmission data is actual data, HOLDPrimitive is set as data to be transmitted this time. If the previous transmission data is OOB, nothing is sent. If the previous transmission data is other primitive, as shown in FIG. 10, the transmission data is generated, and the generated transmission data is passed to the first transmission line transmission unit 18 (S58).

  Next, flow control performed in the transmission line relay device 1 will be described.

  The transmission line relay device 1 is connected to two types of transmission lines, and both transmission lines are not synchronized, so flow control is required.

  When inflow of data from the first transmission path 2 is faster than outflow to the second transmission path 3 and there is a possibility of overflow of the transmission packet buffer 13, the inflow of data from the first transmission path 2 is stopped. The first transmission path transmission unit 18 transmits a flow control command.

  Here, when serial ATA is used as the first transmission path 2, a flow control command HOLDPrimitive is generated and transmitted by the first transmission path transmission unit 18.

  In serial ATA transmission, HOLDAP primitive is returned to the flow control command HOLD Primitive. In order to satisfy the recommended value for the time until this response, when HOLDPrimitive arrives at the first transmission line receiving unit 11 from the first transmission line 2, the first transmission line receiving unit 11 18 is instructed to send HOLDLimitative.

  For the second transmission path 3 as well, flow control is realized by using a flow control mechanism similar to that of serial ATA and putting a management data identifier representing HOLDPrimitive or HOLDAppractive in the packet. Since the flow control command received from the first transmission path 2 is determined not to be transmitted in the transmission permission determination of S19 as described above and is deleted, the flow control used in the first transmission path 2 and the second transmission The flow control of the path 3 is performed independently.

  When there is a possibility of buffer overflow, the reception packet buffer 16 instructs the second transmission path transmission unit 14 to transmit a flow control command so as to stop data transmission from the second transmission path 3.

  When HOLD arrives from the second transmission path 3 to the second transmission path receiving unit 15, the second transmission path receiving unit 15 instructs the second transmission path transmitting unit 14 to transmit HOLD Primitive.

  For flow control, an area for flow control information may be provided in the header of the packet.

  In addition, the flow control command exchanged on the second transmission path 3a may be set separately from the first transmission path 2a and the third transmission path 2b by newly setting a management data identifier different from HOLDPrimitive.

  The flow control method may be performed by a method of instructing the start and end of flow control, instead of always sending back a response to the flow control command as in serial ATA.

  Next, initialization related processing will be described.

  Initialization-related processing is started by three types of OOB. COMRESET from the host side to the device side, COMINIT from the device side to the host side, and bidirectional COMWAKE.

  As the initialization-related processing, transition to the normal state of the power management state, buffer clear, and initialization processing according to the serial ATA initialization sequence are executed.

  In the transition to the normal state of the transmission path, the device and the transmission path between the drive device 4 and the decoding unit 5 are brought into a state where communication can be performed normally.

  For example, when the decoding unit 5 sends a COMRESET to the drive device 4 to make an initialization request, when the initialization request reaches the second transmission line relay device 1b on the third transmission line 2b, If the second transmission path 3a is in the power saving mode, the second transmission path 3a is returned to a state in which normal communication can be performed, and then an initialization request is sent to the second transmission path 3a and the first transmission path relay device. 1a, and transmitted to the drive device 4 via the first transmission path 2a.

  Note that the return of the transmission path to the normal state is not limited to the second transmission path 3a, and may be performed for all devices and all transmission paths.

  The second transmission path 3a is not limited to the power saving mode, and the same applies to other states where communication is impossible.

  The buffer clear is performed so that the state before the initialization request and the accumulated data do not adversely affect after the initialization request.

  When the second transmission line relay device 1b receives the OOB, the data stored in each buffer is cleared. Further, in order to clear the data being transmitted on the second transmission path 3a, the data received from the second transmission path 3a is discarded, and the data transmission to the second transmission path 3a is not performed.

  The serial ATA transmission initialization process sequence has a part in which the response time is strictly defined. When initialization process is performed via the two transmission line relay apparatuses 1a and 1b and the second transmission line 3a, There are parts that cannot meet the response time. With respect to the sequence of that portion, the drive device 4 connected via the first transmission line 2a and the first transmission line relay device 1a, and the third connection connected via the third transmission line 2b. The transmission line relay apparatus 1b and the decoding unit 5 of the transmission line 2 are separately performed.

  FIG. 11 shows an initialization sequence performed between the directly connected serial ATA host and the device.

  FIG. 12 is a diagram showing an initialization sequence when an initialization request is issued from the decoding unit 5 by COMRESET in the configuration of FIG.

  In FIG. 12, COMWAKE from the device side to the host side in the initialization sequence of serial ATA and before the SYNC Primitive from the device side to the host side are serial ATA (first transmission path 2a, third transmission path 2b). This is done by returning a direct response between directly connected devices. The processing during this time is omitted because it is in accordance with the serial ATA specification and is in FIG.

  Note that the sequence may be advanced only between devices that are directly connected from an earlier stage, such as COMINIT from the device side to the host side in the initialization sequence.

  Note that the process of returning a direct response between devices directly connected via the first transmission path 2a and the third transmission path 2b as described above is, for example, a response to returning from the power saving mode in addition to the initialization process. It may be performed in a sequence.

  Regarding the initialization-related processing, the second transmission path relay device 1b connected to the host-side serial ATA equipment and the first transmission path relay equipment 1a connected to the device-side serial ATA equipment differ in operation. do.

  Only the second transmission line relay device 1b realizes the initialization sequence by following the state transitions of the normal mode, the first initialization mode, and the second initialization mode shown in FIG.

  The initial state of the second transmission line relay device 1b starts from the normal mode. In the normal mode, transmission between the second transmission path 3a and the third transmission path 2b follows the above processing.

  When COMRESET is received from the decoding unit 5, the mode is changed to the first initialization mode.

  In the first initialization mode, the reception data from the third transmission path 2b transmits only COMRESET to the second transmission path 3a. Also, no received data from the second transmission path 3a is transmitted to the third transmission path 2b.

  When COMINIT is received from the second transmission path 3a during the first initialization mode, the mode transitions to the second initialization mode.

  In the second initialization mode, received data from the third transmission line 2b is transmitted only COMRESET and COMWAKE to the second transmission line 3a. Also, no received data from the second transmission path 3a is transmitted to the third transmission path 2b.

  When SYNCP primitive is transmitted to the third transmission line 2b during the second initialization mode and SYNCP primitive is received from the second transmission line 3a, the process returns to the normal mode as normal termination of the initialization process sequence.

  If COMRESET is received from the third transmission line 2b during the second initialization mode, the process returns to the first initialization mode.

  Further, when COMWAKE or COMINIT is received from the second transmission path 3a in the normal mode or when COMWAKE is received from the third transmission path 2b, the mode is directly shifted to the second initialization mode.

  The state transition during the initialization process is not limited to the above. For example, the normal end condition may be reception from the second transmission path 3a of X_RDYPrimitive indicating the start of normal transmission to the second transmission path relay device 1b. .

  In the above embodiment, for convenience of explanation, the first transmission path relay device 1a and the second transmission path relay device 1b have substantially the same configuration, but the first transmission path 2a and the third transmission path are the same. If the path 2b is a transmission path according to a different standard, naturally the internal processing of the transmission path relay device 1 is also different.

  Further, in the transmission line relay device 1 according to the present embodiment, blocks in the direction opposite to the blocks from the drive device 4 toward the display device 6 are combined into one device. The display device 6 may be configured separately as two devices opposite to the direction.

  Further, the second transmission path relay device 1b and the decoding unit 5 are integrated and the third transmission path 2b is not provided, or the drive device 4 and the first transmission path relay device 1a are integrated and the first transmission path relay device 1a is integrated. It is good also as a structure which does not provide the transmission line 2a.

  In the embodiment described so far, there is one drive device 4, but FIG. 14 shows an example of a transmission device using the transmission line relay device 1 when two drive devices are provided.

  In this case, the first transmission path 2 is composed of the first transmission path 2aa and the first transmission path 2ab (third transmission path), and the first transmission path relay device 1a includes the first transmission path 2aa and the first transmission path 2aa. Each of the data sent from two of the one transmission line 2ab is received, and each data is compressed by the first transmission line reception data compression unit 121 in the same manner as when there is a single transmission line. The data is stored in the first transmission path reception data buffer 122 provided for each transmission path. When packetizing each of the plurality of first transmission path reception data buffers 122, in order to determine which transmission path the data is sent from, the transmission path is identified in the packet as shown in FIG. A transmission path identifier is assigned in advance. Then, the data is relayed to the second transmission path 3a.

  As a result, even when data is received from a plurality of drive devices, the data can be transmitted on the second transmission line having a low transmission rate while suppressing a decrease in throughput in a differentiated manner.

  As described above, the transmission line relay device according to the present invention has an effect of suppressing a reduction in throughput even when relaying to a transmission line with a lower transmission speed, and transmission data between different transmission lines. It is useful as a transmission line relay device or the like for relaying.

The block diagram of the transmission-line relay apparatus of one embodiment of this invention Block diagram of a transmission apparatus using the transmission line relay apparatus of an embodiment of the present invention The flowchart explaining the packet generation process of the transmission line relay apparatus of one embodiment of this invention FIG. 3 is a flowchart continued from the flowchart of FIG. 3 for explaining the packet generation processing of the transmission line relay device according to the embodiment of the present invention. Configuration diagram of a packet of a transmission line relay device according to an embodiment of the present invention Correspondence table between Primitive and OOB and management data identifier of transmission line relay apparatus according to one embodiment of the present invention Determination table for determining whether transmission is possible or not in the transmission line relay device according to the embodiment of the present invention The flowchart explaining the serial ATA data generation process of the transmission line relay apparatus of one embodiment of this invention The flowchart explaining the process by the data part of the packet of the transmission line relay apparatus of one embodiment of this invention Correspondence table for determining transmission data from previous transmission data of transmission line relay device of one embodiment of the present invention Sequence diagram showing initialization process in serial ATA State transition diagram for explaining the operation of the initialization processing of the transmission line relay device of the embodiment of the present invention The sequence diagram explaining the operation | movement of the initialization process of the transmission line relay apparatus of one embodiment of this invention The block diagram of another transmission apparatus using the transmission line relay apparatus of one embodiment of this invention Configuration diagram of another packet of the transmission line relay device of one embodiment of the present invention Block diagram of a conventional transmission device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Transmission path relay apparatus 11 1st transmission path receiving part 12 2nd transmission path transmission data generation part 121 1st transmission path reception data compression part 122 1st transmission path reception data buffer 13 Transmission packet buffer 14 2nd transmission path transmission part 15 Second transmission line reception unit 16 Receive packet buffer 17 First transmission line transmission data generation unit 171 First transmission line transmission data return unit 172 First transmission line transmission data buffer 18 First transmission line transmission unit 2 First transmission line 21 Reception Signal line 22 Transmission signal line 3 Second transmission line 31 Reception signal line 32 Transmission signal line 1a First transmission line relay device 1b Second transmission line relay device 2a First transmission line 2b Third transmission line 3a Second Transmission path 4 Drive device 5 Decoding unit 6 Display device 210 Transmission device 211 Drive device 212 First packet processing unit 212a Buffer 213 First transmission path interface unit 214 first stream data transmission line 220 transmission path 230 receiving apparatus 231 decoding unit 232 the second packet processing unit 232a buffer 233 second transmission path interface unit 234 second stream data transmission path 240 display

Claims (18)

A transmission path relay device that relays between a first transmission path that transmits the actual data to be transmitted and transmission management data separately, and a second transmission path that has a lower transmission speed than the first transmission path,
First transmission path receiving means for receiving data from the first transmission path;
First transmission line reception data compression means for compressing at least the management data of the data received by the first transmission line reception means;
A transmission line relay apparatus comprising: second transmission line transmission means for transmitting data processed by the first transmission line reception data compression means to the second transmission line. From the actual data and management data processed by the first transmission path reception data compression means, a flag for identifying whether the data to be transmitted is the actual data or the management data is added, and the continuous actual data or A second transmission path transmission data generating means for generating a packet so as to combine the management data into one packet;
The transmission path relay device according to claim 1, wherein the second transmission path transmission means transmits the packet generated by the second transmission path transmission data generation means to the second transmission path. The first transmission line is a serial transmission line, and the first transmission line reception data compression means converts the real data converted from 8-bit data received from the first transmission line into 10-bit data from 10-bit data. The transmission path relay apparatus according to claim 2, wherein the transmission path relay apparatus converts the data into 8-bit data. The first transmission path receiving means receives an OOB signal that transmits a message according to a waveform pattern, and the second transmission path transmission data generating means indicates an OOB signal in which the flag is set in the management data from the OOB signal. The transmission line relay apparatus according to claim 3, wherein the packet is created. 4. The transmission line relay device according to claim 3, wherein the first transmission line is serial ATA, and the first transmission line reception data compression unit deletes all primitives received from the first transmission line. . The first transmission line is a serial ATA, and the first transmission line reception data compressing means deletes a predetermined number of primitives when receiving the same type of primitive continuously from the first transmission line. The transmission line relay apparatus according to claim 3, wherein The first transmission line is a serial ATA, and the first transmission line reception data compression unit deletes all received primitives or is continuous depending on the type of primitive received from the first transmission line. 4. The transmission line relay apparatus according to claim 3, wherein a predetermined number of primitives of the same type are deleted or left to be switched. 7. The first transmission path received data compression means replaces the primitive that has not been deleted among the primitives received from the first transmission path with an identifier having a smaller data amount than the primitive. Or the transmission line relay device according to 7; The first transmission path received data compression means converts the primitives not deleted from the primitives received from the first transmission path from 10 bits to 8 bits and transmits the lower 3 bytes of the conversion result The transmission line relay apparatus according to claim 6 or 7, wherein: The first transmission path receiving means determines whether the data received from the first transmission path needs a response immediately. If it is determined that a response is required immediately, a response corresponding to the data is sent to the first transmission path. The transmission line relay apparatus according to claim 1, wherein the transmission line relay apparatus is transmitted. The first transmission path is a serial ATA, and the first transmission path receiving means includes a serial ATA initialization sequence from transmission / reception between a COMWAKE device and a host to transmission of an ALIGN from the host to the device. 11. The transmission line relay apparatus according to claim 10, wherein it is determined that a response is required immediately for data received in the meantime. 11. The transmission path relay according to claim 10, wherein the first transmission path is a serial ATA, and the first transmission path receiving means determines that a response is required immediately upon receiving the HOLD primitive of the serial ATA. apparatus. A reception packet buffer that temporarily stores data received from the second transmission path; and a first transmission path transmission data generation unit that generates data to be transmitted to the first transmission path when the reception packet buffer is empty; The transmission path relay device according to claim 1, comprising: 14. The transmission path relay according to claim 13, wherein the first transmission path transmission data generating means generates data to be transmitted to the first transmission path based on data transmitted to the first transmission path last time. apparatus. A reception packet buffer for temporarily storing packets received from the second transmission path; and a transmission packet buffer for temporarily storing packets to be transmitted to the second transmission path. 2. The transmission line relay apparatus according to claim 1, wherein when a reset request is received from one of the two transmission lines, both the reception packet buffer and the transmission packet buffer are emptied. 2. The transmission line relay device according to claim 1, further comprising return means for returning the second transmission path to a communication enable state when the second transmission path is in a communication disabled state. 2. The transmission line relay apparatus according to claim 1, wherein flow control is performed independently on the first transmission line and the second transmission line. The first transmission line receiving means receives data from a plurality of transmission lines,
A transmission path identifier adding means for adding a transmission path identifier capable of distinguishing the plurality of transmission paths;
The first transmission line reception data compression means compresses data from the plurality of transmission lines received by the first transmission line reception means,
2. The transmission line relay apparatus according to claim 1, wherein the data obtained by adding the transmission line identifier to the data processed by the first transmission line reception data compression unit is transmitted to the second transmission line.

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