JPH04367053A - Channel system - Google Patents

Abstract

PURPOSE:To improve the answering performance and the throughput in a channel system where a channel device is connected to the input/output devices via a loop type serial transmission line and an interface operation is carried out in a frame form. CONSTITUTION:A channel device 15 is connected to the input/output devices 1-4 via a loop type serial transmission line 16, and the input/output interface operations are performed between the device 15 and the devices 1-4 by circulating the frames coded for each function via the line 16. In such a channel system, a bypass route 21 which secures the direct connection between the device 15 and a specific input/output device is set between the lines 16 which secure the connection between the device 15 and the devices 1-4. Then the frame that has completed the data input/output processing to the input/output device is transferred to the device 15 bia the route 21.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a channel system for an information processing device, and in particular, the present invention relates to a channel system for an information processing device, and in particular, for controlling input/output interface operations between a channel device and an input/output device in an information processing device, in a high-bandwidth system such as optical communication. This relates to a channel system that performs long-distance serial transmission via a transmission line in which serial transmission lines are connected in a loop.

0002

[Prior Art] Conventionally, as a technology for increasing the distance between a central processing unit and input/output devices using a serial transmission path, a central channel device and a terminal channel device are connected in a loop, and data transfer is performed in a frame. There is a channel control method that uses As a channel control method using such a serial transmission line, for example, a channel control method described in Japanese Patent Application Laid-Open No. 2-83759 is known. A channel system for an information processing device using this channel control method connects a channel device and an input/output device provided in the information processing device with a loop-shaped serial transmission path, and connects the channel device to the serial transmission path. , sends a frame that encodes the interface operation in functional units,
This is a system that performs input/output interface operations.

0003

[Problems to be Solved by the Invention] However, in the above-described channel system, since the channel device and the plurality of input/output devices are connected in series through a serial transmission path in a loop, are scattered in remote locations, the response time of input/output devices installed nearby is the same as that of the input/output device installed in the farthest location, resulting in a very slow response time. There is.

[0004] For this reason, when the next command must be issued in real time in response to the operation of an input/output device (such as in a command chain for a magnetic disk drive), it is recommended to use a long loop length for the input/output device. There are some drawbacks such as not having one.

The present invention has been made to solve such problems, and an object of the present invention is to connect a channel device and an input/output device with a loop-shaped serial transmission line, and to perform an interface operation. The purpose of this invention is to improve response performance and throughput in a channel system that performs communication in a frame format.

[0006]

[Means for Solving the Problems] In order to achieve the above object, the channel system of the present invention connects a channel device and a plurality of input/output devices in a loop through a serial transmission line, and connects the channel device and each input/output device. A loop that connects a channel device and multiple input/output devices in a channel system that performs input/output interface operations by circulating frames in which the interface operations with the input/output devices are coded in functional units over a serial transmission path. A bypass route that directly connects a specific input/output device and the channel device is inserted in the serial transmission path of It is characterized in that it is transferred to a channel device.

[0007]

[Operation] The channel system of the present invention provides a bypass route that directly connects a specific input/output device and the channel device on a transmission loop in which a channel device and a plurality of input/output devices are connected in a loop through a serial transmission path. Provided in between. Then, frames for which data input/output processing has already been completed between the input/output device and the input/output device are transferred to the channel device via the bypass route. When the bypass route is used instead of the loop-shaped serial transmission path, the response time becomes faster, so real-time processing of input/output interface operations becomes possible.

[0008] In this way, a bypass route that directly connects a specific input/output device and a channel device on a loop is realized by interposing a bypass control device and providing a bypass control flag in a frame circulating on a serial transmission path. The bypass control flag controls the frame that has already exchanged data with the input/output device to be transferred directly to the channel device via the bypass route without being transferred to the lower input/output device. In addition, when adding input/output devices to a channel system that is already configured in a loop, use the transmission line connecting the lowest input/output device to the channel device as a bypass route. By using this configuration, a bypass route can be constructed economically.

[0009] As a result, when passing through a bypass route instead of a loop-shaped serial transmission line, the response time becomes faster, so real-time processing becomes possible.
By installing a bypass control device in the middle of a loop-shaped serial transmission path, the throughput of the entire system can be improved.

0010

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a system configuration diagram showing the overall configuration of a channel system according to an embodiment of the present invention, and FIG. 2 is a diagram showing a system configuration in which a bypass route is provided in the channel system. This will be explained with reference to FIGS. 1 and 2. 1 and 2, 1 to 4 are a plurality of input/output devices, 10 is a central processing unit (CPU), 11 is a main storage device (MS), and 12 is a main storage control unit (SCU) 13
is an instruction processing unit (IPU), and 14 is a channel control unit (
CHC), 15 is a channel device (CH). The data processing system includes input/output devices 1 to 4 of peripheral devices to a central processing unit 10 composed of a main storage device 11, a main storage control unit 12, an instruction processing device 13, a channel control device 14, and a channel device 15. are connected and configured. The input/output devices 1 to 4 are connected via a channel device 15 in the central processing unit 10 and perform input/output interface operations with the channel device 15.

Channel device 15 is controlled by channel control device 14 . The channel control device 14 actually accommodates a plurality of channel devices 15, and the main storage device 11
Reading channel commands from, channel device 15
It performs processing such as writing the completion result of the data transfer channel command between the main storage device 11 and the main storage device 11 into the main storage device 11. From the channel device 15, a plurality of input/output devices 1 to 4 are connected in series by a long distance bus 16 using a serial interface such as an optical fiber cable.
A loop-shaped serial transmission path is formed, and this long distance bus 16 connects the channel device 15 and the plurality of input/output devices 1 to 4. Multiple input/output devices 1~
Each of 4 is provided with channel interface control units 5 to 8 for connecting the long-distance bus 16 via a serial interface.

If it is assumed that the input/output devices 1 to 4 for the central processing unit 10 are scattered at remote locations, the loop length by the long distance bus 16 of the serial interface becomes very long. The transmission time of frames circulating through the serial transmission path becomes longer. For this reason, for example, for the input/output device 2 that requires a high-speed response, a bypass route is provided to directly transfer frames for which data input/output processing has been completed between the input/output device 2 and the channel device 15. . In order to install this bypass route, for example, as shown in FIG. 2, a bypass control device 20 is provided following the input/output device 2, and a bypass route is configured that directly connects the bypass control device 20 to the channel device 15. A bus 21 is connected. In addition, from the bypass control device 20, a connection bus 22 for the serial transmission path of the normal loop is connected.
is connected to the channel interface control unit 7 of the next input device 3.

Data transfer between the channel device 15, the input/output devices 1 to 4, and the bypass control device 20 is performed in frame format. Therefore, each input/output device 1, 2, 3, 4
have channel interface control units 5, 6, and 7, respectively.
, 8 are provided. Next, the configuration of the interface control unit that transfers frame data in the channel device 15, the input/output devices 1 to 4, and the bypass control device 20 will be described.

FIG. 3 is a diagram showing the configuration of the main part of the input/output interface control section of the channel device, and FIG. 4 is a diagram showing the construction of the main part of the channel interface control section of the input/output device. Moreover, FIG. 5 is a diagram showing the configuration of main parts of the bypass route control section of the bypass control device.

The input/output interface control section of the channel device 15, as shown in FIG. Receive register 3 that temporarily holds the received frame
3, a multiplex circuit 34, a parallel-to-serial conversion circuit 35, and serial-to-parallel conversion circuits 36 and 37. The serial/parallel conversion circuits 36 and 37 are circuits that convert serial data frames received from the serial transmission lines (16, 21) into parallel data, and the frames converted into parallel data are sent to the reception register via the multiplex circuit 34. 37. The frame of coded data of the functional unit of the input/output interface operation temporarily held in the reception register 33 is as follows:
It is input to the processor 31. The processor 31 extracts coded data in functional units of input/output interface operations transmitted from each input/output device from the frame, checks the operation of the input/output device, and instructs the operation of the input/output device. It generates coded data for functional units of input/output interface operations to transmit frame data to be transmitted to the transmission register 32. Transmission register 32
The parallel data is converted into serial data by the parallel-serial conversion circuit 35 and sent to the serial transmission line (16).

A frame issued to an input/output device carries information for the channel device in each input/output device and returns to the channel device. The returned frame is set in the reception register 33 via the serial/parallel conversion circuit 37 or the serial/parallel conversion circuit 36 of the channel device 15. The processor 31 examines this and extracts information from the input/output device inserted in the frame. The channel device includes a serial/parallel conversion circuit 37 that receives frames from the normal loop route bus 16 and a bypass route bus 21.
A serial-to-parallel conversion circuit 36 is provided for receiving frames from. There are multiple such serial-to-parallel conversion circuits,
It shall be possible to connect to multiple bypass routes. The multiplexer circuit 34 connected to the serial/parallel conversion circuit 36 and the serial/parallel conversion circuit 37 can handle frames from either the loop serial transmission line bus 16 or the bypass route bus 21, and can handle multiple frames. It controls the bypass route.

Furthermore, as shown in FIG. 4, the channel interface control section of each input/output device is centered around a processor 43 that performs interface control processing, and receives data from the serial transmission line (16) from the channel device side. A serial/parallel conversion circuit 41 that converts serial data of frame data into parallel data, a reception register 42 that temporarily holds the frame data converted to parallel data, and a reception register 42 that temporarily holds frames of transmission data to be sent to the next input/output device. It consists of a transmission register 44 and a parallel/serial conversion circuit 45 that converts the frame data of the transmission register into serial data and sends it to the serial transmission path (16). The processor 43 of the channel interface control unit is connected to an input/output control basic unit 46 that performs basic control operations for the input/output device. It sends control commands for input/output interface control operations that have been performed, receives confirmation data such as status flags from the input/output control basic unit 46, updates the field data of the input/output device in the frame data, and Generate data and send it to the Charnet device.

As shown in FIG. 5, the bypass control device 20 includes a processor 53 that performs frame bypass transmission control.
A serial/parallel conversion circuit 51 which converts the serial data of frame data received from the serial transmission line (16) from the upper-level input/output device into parallel data, and temporarily holds the frame data converted into parallel data. a bypass register 54 that temporarily holds frames of transmission data to be sent to the channel device via the bypass route, and a bypass register 54 that converts the frame data in the bypass register 54 into serial data and sends it to the serial transmission line (21) of the bypass route. A parallel-to-serial conversion circuit 55 for sending data, a lower register 56 for temporarily holding frames of transmission data to be sent to a lower input/output device, and a serial transmission line (22 )
and a parallel-to-serial conversion circuit 57 for sending data to The processor 55 determines whether a bypass control flag is added to the data frame received from the higher-level input/output device, and either transmits the data frame to the bus 16 to the lower-level input/output device or bypasses the data frame. control whether to send the data to the bus 22 of the bypass route back to the channel device.

FIG. 6 is a diagram showing an example of frames transmitted and received between a channel device and an input/output device. Figure 6(A)
6(B) shows the format of the startup frame, FIG. 6(B) shows the format of the data frame, and FIG. 6(C) shows the format of the startup frame.
shows the format of the status frame. In the frame format shown in FIG. 6, a "delimiter" is a special symbol indicating the beginning and end of a frame, and is created by a parallel-to-serial conversion circuit. The "control byte" is a code indicating the type of frame, and is generated by the processor 31 of the channel device and the processor 43 of the channel interface section of the input/output device. Each frame is transmitted from the transmission register via a parallel-to-serial conversion circuit. In addition, the "cyclic check code" is a code for performing a cyclic check of the frame.
It is created using a parallel-to-serial conversion circuit and checked using a serial-to-parallel conversion circuit. The “input/output device number” is a number indicating which input/output device the frame is sent to, is generated by the processor 31 of the channel device, and is sent from the transmission register 32 via the parallel/serial conversion circuit 35. The "transfer count" is the number of bytes of data that an input/output device receives from a channel or sends to a channel.
is generated by the transmission register 44 and sent to the parallel-to-serial conversion circuit 45.
Sent via . The "bypass control flag" is a flag used by the bypass control device 20 to select a bus for a bypass route. When the bypass route is not allowed to pass, the "bypass control flag" is a flag used by the bypass control device 20 to select a bus for a bypass route. Send “0”.

By the way, for example, as shown in FIG. 4, in the input/output device 1, each data of the frame received from the channel device side via the bus 16 is sent to the serial/parallel converter circuit 4.
1 to the reception register 42. The processor 43 checks the input/output device number of this intraframe data. If the input/output device number matches the own device number given in advance, the control byte is further checked and processing is performed for each function frame. In this case, in processing the data frame and status frame, read data, input/output device status, and device status bytes are inserted into the frame, and the bypass control flag is set to "1" and set in the transmission register 44. The lower input/output devices 2 to 4 or the bypass control device 20 via the parallel-to-serial conversion circuit 45
Send to. Further, if the input/output device number does not match the own device number, the received frame is set as is in the transmission register 44 without changing the data within the frame,
The frame is sent out to the bus 16 via the parallel-to-serial conversion circuit 45 and transmitted to the lower-order input/output devices 2 to 4 or the bypass control device 20.

When the bypass control device 20 receives a frame from the host device, it checks the bypass control flag in the frame, and if the flag is “1”, sets the frame in the bypass register 54 and bypasses it. The frame is sent to the channel device via the bus 21 of the root serial transmission line, and if the bypass control flag is "0", the frame is sent to the lower input/output via the lower register 56. Send to device.

As described above, in the channel system here, the channel device 15 and the plurality of input/output devices 1 to 4 are connected to each other.
A bypass route that directly connects a specific input/output device 2 and the channel device 15 is provided on a transmission loop connected by a serial transmission bus 16 in a loop shape. Then, the frame for which data input/output processing has already been completed between the input/output devices 1 and 2 is transferred to the channel device 15 via the bypass route bus 21. Therefore, when the bus 21 of the bypass route is used instead of the bus 16 of the loop-shaped serial transmission line, the response time becomes faster and real-time processing of the input/output interface operation becomes possible.

A bypass route bus 21 that directly connects a specific input/output device 2 of the bus 16 on the loop to the channel device 15 is provided by inserting a bypass control device 20, and a bypass control device 20 is inserted in the frame circulating on the serial transmission path. Control flag (
Fig. 6) is provided to select a route. As a result, frames that have already exchanged data with the input/output device due to the bypass control flag are not transferred to the lower input/output device,
It is possible to control the transfer directly to the channel device via the bypass route.

[0024] As a result, when passing through a bypass route instead of a loop-shaped serial transmission line, the response time becomes faster, so real-time processing becomes possible.
By installing a bypass control device in the middle of a loop-shaped serial transmission path, the throughput of the entire system can be improved.

FIG. 7 is a diagram illustrating an example of a system configuration when a bypass control device is installed in a channel system of serial transmission lines. This is an example of a configuration in which the channel device 15 and the input/output devices 1 to 4 are connected by a loop serial transmission line bus 16, and the input/output device 3 transfers data frequently. be. In this case, a bypass control device 61 is installed on the transmission side of the input/output device 3, and a bypass route 62 to the channel device 15 is provided. In this case, along with the installation of the bypass control device 61, a bus 63 and a bus 64 are provided for the route of the loop-shaped bus 16 that passes through the bypass control device 61. This reduces the rate at which frames are sent to the lower-level input/output device 4 and increases the number of frames sent directly to the channel device 15, improving the throughput of the entire system.

FIG. 8 is a diagram illustrating another system configuration example in which a bypass control device is installed in a channel system of serial transmission lines. This system configuration example is a system configuration example in which a new input/output device 65 is added in a channel system in which a channel device 15 and input/output devices 1 to 3 are connected by a loop serial transmission line bus 16. It shows. In this case, a bus 66 is connected between the input/output device 3 and the additional input/output device 65, and a bus 66 is connected between the channel device 15 and the additional input/output device 65.
Since the bus 67 between the channel device 15 and the input/output device 3 is newly connected, the bus 70 of the serial transmission path between the channel device 15 and the input/output device 3 remains. In this case, the bus 70 of this serial transmission path is not eliminated, but is effectively used as a bypass route, and a bypass control device 68 is inserted between the input/output device 3, the additional input/output device 65, and the channel device 15. and perform bypass control as described above. Therefore, in the case of such a channel system configuration, if the frame is for the existing input/output devices 1 to 3, the frame is not sent to the additional input/output device 65 but directly to the channel device 15. Therefore, throughput can be improved.

In this way, when adding input/output devices to a channel system that is already configured in a loop, it is necessary to install a bypass device from the lowest input/output device to the channel device. By configuring the transmission line connected to as a bypass route,
A bypass route can be constructed economically.

FIG. 9 is a diagram illustrating yet another system configuration example in which a bypass control device is installed in a channel system of serial transmission lines. This system configuration example is a modification of the channel system to further increase speed. FIGS. 10 and 11 are block diagrams showing the configurations of main parts of a bypass control device and a channel device, respectively, in this modification. Figures 9 to 11
Explain with reference to.

The system configuration in this case is, as shown in FIG. 9, in a channel system composed of loop-shaped serial transmission lines, in which the loop-shaped serial transmission lines are connected to a first loop bus 71 and a second loop bus 72. A bypass control device 73 is inserted at the intermediate point, and a bypass route 74 connects the bypass control device 73 and the channel device 75. Then, the frame transfer direction of the input/output devices 3 and 4 is changed from the channel device 75 to the bypass control device 73 (reverse direction). In the channel device 75, as shown in FIG.
The frame generated by and the input/output device 4.

On the other hand, on the input/output device side, frames are exchanged under the control described above, and each frame reaches the bypass control device 73. In the bypass control device 73, as shown in FIG. Second loop bus 72 from output device 3, serial/parallel conversion circuit 84
The frame received via the second receiving register 84 is received by the second receiving register 84. The processor 81 in the bypass control device 73 sets the frame whose bypass control flag is "1" among the received frames in the transmission register 86, so that the frame that has been accessed with the input/output devices 1 to 4 is Channel device 75 via bypass route 74
Return to In the channel device 75, the frame returned via the bypass route 74 is received by the reception register 93 via the serial/parallel conversion circuit 96, and is supplied to the processor 92.

[0031] By using such a transfer method,
Since the frame transmitted from the channel device returns to the channel device 75 from the bypass control device 73 after going around the loop approximately half way, the throughput is dramatically improved.

[0032]

As explained above, according to the channel system of the present invention, a channel device and an input/output device are connected through a loop-shaped serial transmission path, and data for input/output interface operation is transmitted through the serial transmission path. In a channel system that performs a channel interface operation, the following effects can be obtained. That is, (1) By providing a bypass route in the middle of the loop, response time becomes faster and processing can be performed in real time. Additionally, the throughput of the entire system can be improved. (2) When adding input/output devices in a loop, the bypass route can be constructed economically by using the existing transmission line as a bypass. (3) When a bypass is provided at the midpoint of the loop, the frame returns to the channel device approximately halfway through the loop, so response time and throughput can be dramatically improved.

[Brief explanation of the drawing]

FIG. 1 is a system configuration diagram showing the overall configuration of a channel system according to an embodiment of the present invention;

[Figure 2] Figure 2
is a diagram showing a system configuration with a bypass route in the channel system,

FIG. 3 is a diagram showing the configuration of the main parts of the input/output interface control section of the channel device;

FIG. 4 is a diagram showing the configuration of main parts of a channel interface control section in an input/output device;

FIG. 5 is a diagram showing the configuration of the main parts of the bypass route control section of the bypass control device;

FIG. 6 is a diagram showing an example of a frame transmitted and received between a channel device and an input/output device; FIG. 6(A) shows the format of a startup frame, and FIG. 6(B) shows a format of a data frame. The format of the status frame is shown in FIG. 6(C).

FIG. 7 is a diagram illustrating an example of a system configuration when a bypass control device is installed in a channel system of a serial transmission line;

FIG. 8 is a diagram illustrating another system configuration example when a bypass control device is installed in a channel system of a serial transmission line;

FIG. 9 is a diagram illustrating yet another system configuration example when a bypass control device is installed in a serial transmission line channel system;

FIG. 10 is a block diagram showing the configuration of main parts of the bypass control device in the system configuration example of FIG. 9;

[Figure 11
FIG. 11 is a block diagram showing the configuration of main parts of a bypass control device and a channel device in the example system configuration of FIG. 9.

[Explanation of symbols]

1, 2, 3, 4, 65 Input/output device 5, 6, 7, 8 Channel interface control unit 10
Central processing unit (CPU) 11 Main memory (MS) 12 Main memory control unit (SCU) 13 Instruction processing unit (IPU) 14 Channel control unit (CHC) 15, 75 Channel device (CH) 16, 71, 72 Serial transmission bus 20,61
, 68, 73 bypass control device 21, 62, 70,
74 Bypass route buses 22, 63, 64, 66
, 67 Loop transmission line buses 31, 43, 53, 8
1,91 Processor 32, 42, 86, 92 Transmission register 33, 44, 52, 83, 84, 93 Reception register 34 Multiplex circuit 35, 45, 55, 57, 87, 94, 95 Parallel-serial conversion circuit 36, 37 , 41, 51, 82, 85, 96 Serial-to-parallel conversion circuit 46 Input/output control basic section 54 Bypass register 56 Lower side register

Claims (1)

[Claims] Claim 1: A channel device and a plurality of input/output devices are connected in a loop through a serial transmission path, and frames in which interface operations between the channel device and each input/output device are coded in functional units are serially transmitted. In a channel system that circulates through a transmission path and performs input/output interface operations, a specific input/output device and the channel device are directly connected to a loop-shaped serial transmission path that connects the channel device and multiple input/output devices. A channel system is characterized in that a bypass route is interpolated to transfer a frame that has already undergone data input/output processing between the input/output device and the input/output device to the channel device via the bypass route.