JPS6355620A - input/output control device - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an input/output control device that controls input/output devices according to commands from a central processing unit in an input/output device control system, and particularly relates to an input/output control device that controls input/output devices in accordance with commands from a central processing unit side. [Prior art] Generally, in an input/output device control system, multiple input/output devices are connected via one channel device. Output control devices or input/output devices are connected to the central processing unit, and input/output operation instructions from the central processing unit to each input/output control device or input/output device are performed by input/output commands. The device processes them as a group of a series of channel commands.

Channel commands consist of various commands such as control system commands for positioning the head and arm on the input/output device at predetermined positions, and data transfer commands for reading and writing information stored on the input/output device. is,
Conventionally, reading and writing processing of stored information on an input/output device has been realized by sequentially executing a combination of control system commands and data transfer system commands.

In particular, for example, in a magnetic disk control device, the control system commands and data transfer system commands include (1) a seek command for positioning the head arm at a predetermined cylinder or door address; and (2) a seek command for positioning the head arm at a predetermined sector. Set sector command for positioning the arm (3) Search command for positioning the head and arm at a predetermined record (4) Read command for data transfer of storage information of a predetermined record or command during write By sequentially executing steps (1) to (4), it reads and writes the stored information of a given record, and at the same time, the physical movement of the head arm during the seek command and set sector command is performed. During this time, the channel device is disconnected from the magnetic disk control device to release the channel device, and then re-coupled (after the transfer is completed) to perform subsequent command operations, increasing the usage efficiency of the channel device. .

On the other hand, as described in Japanese Patent Application Laid-Open No. 55-34795, there is a system in which several types of command operations are performed with one command 2.

[Problem that the invention seeks to solve]

In the conventional technology described above, the usage efficiency of the channel device is improved during the physical movement time of the head arm, but on the other hand, the channel device and the input/output control device are There has been a problem in that decoupling and recoupling processes occur frequently, and the usage efficiency of the channel device during this process is reduced.

On the other hand, as described in Japanese Patent Laid-Open No. 55-34795, if several types of commands are performed with one command, the above-mentioned problem of reduced usage efficiency of the channel device can be solved. By creating new commands, there is no compatibility with existing programs such as operating systems, and read and write processing is related to the basic operation of input/output devices, so existing programs must be modified considerably. The problem is that it requires

It is an object of the present invention to maintain compatibility with programs such as existing operating systems and to solve the problem of reduced usage efficiency of conventional channel devices without requiring modification of existing programs. The object of the present invention is to provide an input/output control device that provides good access to input/output devices.

[Means for solving problems]

The above purpose is to have the control logic part of the input/output control device receive a control command for positioning the head arm from the channel device to which the input/output control number # is connected, and the specified positioning It has a function of sequentially accumulating information, and when a read command or write command is received, the positioning of the head arm is determined based on the accumulated positioning information before starting data transfer. This is achieved by providing a function that performs the process of decoupling and recoupling the channel device and input/output control device in one go.

[Effect]

The function of accumulating positioning information is to input the positioning information specified by the control system command for positioning the arm to the input/output device that receives it from the central processing unit via the channel device. Control in output control device
The information is accumulated sequentially in the local memory within the logic circuit, and the accumulated positioning information defines the location of the stored information within the input/output device to which read and write processing is to be performed. For example, in a magnetic disk control device, when a seek command or set sector command is received, the cylinder, head, sector address, etc. where the head arm of the input/output device specified by each command should be positioned is displayed on the next page. It will be accumulated.

In addition, the positioning function performs operations all at once.The positioning information stored in the local memory is analyzed by the microprogram processing section of the control logic circuit in the input/output control device, and the positioning information is actually processed by the head. At the start of read and write processing that requires arm positioning, positioning operations such as seek operations, set sector operations, etc. are performed in batches.

As a result, when performing read/write processing of the input/output device, the process of uncoupling and recoupling between the channel device and the input/output control device can be completed only once, thereby improving the usage efficiency of the channel device. Furthermore, positioning can maintain compatibility with existing programs by accumulating information, and does not require modification of existing programs.

[Implementation]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows an overall configuration diagram of an embodiment of the present invention.

In Fig. 1, 3 is the input/output system) s prize, and the CPU
Side interface circuit 5. Serial/parallel conversion circuit 6, access logic circuit 71 control
Logic circuit 8. It consists of an I10 side interface circuit 9. The CPU side interface circuit 5 of the input/output control device 3 is connected to the central processing unit 1 via the channel device 2, and the I10 side interface circuit 9 is connected to the input/output device 4. Here, it is assumed that the input/output device is a disk device.

The control logic circuit 8 is the input/output tlJ control device 3
As shown in the second figure, it is composed of ζ, a processing unit 20 such as a microprocessor, a microprogram), a memory (RAM) 21, and a local memory (LtAbi) 22. Ru. The control logic circuit 8 controls the access logic circuit 7, the serial/parallel conversion circuit 6, etc. based on commands received from the channel device 2 via the interface circuit 5, and performs read and write processing for the disk device 4.

The microprogram required for this process is ↑Control Memory 2
1 is stored in the microprogram processing unit 20.
1 (desired processing is achieved.In the local memory 22, among the received commands, information on the positioning of the head and arm specified by the control system command is sequentially stored, and the data transfer system command At the time of receiving the data and before starting data transfer, the control logic circuit 8 controls the access φ logic circuit 7 to position the head arm of the input/output device based on the accumulated nine positioning reports. .

FIG. 3 shows a processing flow of the control logic circuit 8, and the operation will be explained below using this flow.

First, a startup sequence is executed by activation from the channel device 2 (step 101) *In this startup sequence, the channel device #2 sends a command to the input/output control device 3, which passes through the interface circuit 5 and controls the・Local memory 22 of logic circuit 8
is stored in

Commands sent include control system commands, data transfer commands, etc. 0th order control logic, rotation j
The processing unit 20 of the i38 decodes the command (step 102) and reads the control memory 21 based on the command.
Execute the microprogram. command is seek
If it is a command, the cylinder address and head address, which are information for positioning the head arm, are received from the channel device 2 via the interface circuit 5, stored in the local memory 22, and at this point, the seek command for the input/output device 4 is sent. The command operation is terminated without any action (step 103), and a command completion report is sent to the channel device 92 (step 104).

When the channel device 2 receives the command completion notification from the input/output control device 3, does it continue to input/output? ! : I & ii Starts the next command for device 3 (step 101
), similarly to the seek command, the processing unit 20 of the control logic circuit 8 decodes the command (step 102), and if the command is a set sector command, the positioning of the head arm is the sector information. After receiving the address from the channel device 2 and similarly storing it in the local memory 22, at this point the command operation is completed without performing a set/sector operation for the input/output device 49 (Step 105), and the address is stored in the local memory 22. The end of the command is reported (step 104).

When the channel number '2 receives the command completion report from the input/output controller 3, it continues to activate the next command for the input/output controller [5 (step 10+), in the same way as the seek command. The processing unit 20 of the logic circuit 8 performs step (1) to decode the command.
02), Command completion report ・If it is a command, the head
For arm positioning, the record address, which is information, is received from the channel device 2 and stored in the local memory 22. At this point, the command operation is completed without performing a search operation for the input/output device 4. Step 1o
6) Reports the completion of the command to the channel device 2 (step 104). When the channel device 2 receives the command completion report from the input/output control device 3, it subsequently starts the next command to the input/output control device #3. (Step +01), the processing unit 20 of the control logic circuit 8 duplicates the command as in the case of the seek command (Step 1o2), and starts data transfer if the command is a read command or a write command. After previously reporting the channel end to the channel device 2 (step 107), releasing the connection between the channel device 2 and the input/output control device 5, and releasing the channel device 2,
The head/arm positions are determined by sequentially performing seek operations, set/sector operations, search operations, etc. based on the information stored in the local memory 22 (step 10B).
After the operation is completed, positioning requests the channel device 2 to reconnect the channel device 2 and the input/output control device 3, and also requests the device end to restart the read command or write command. Report (Step 10)
9) When the channel device 2 receives the device end report from the input/output control device 3, it restarts the read command or write command (step 101).
.

When the processing unit 20 of the control logic circuit 8 of the input/output control device 3 receives the restart of the read command or write command, it starts data transfer at this point (step 110), and after the data transfer is completed, the processing unit 20 of the control logic circuit 8 transfers the data to the channel device 2. Report the completion of the command to (step 104)
.

Although the embodiment shows a case where a disk device is connected to the input/output control device, the present invention is not driven by this, and in the embodiment, the positioning of the head arm is performed as a seek operation. , set/sector operation, and search operation are taken as examples, but the type of positioning operation may differ depending on the connected input/output device.

〔Effect of the invention〕

According to the present invention, it is possible to improve the usage efficiency of channel devices in read and write processing of input/output devices without modifying existing programs, thereby realizing efficient access to input/output devices. There is an effect that it can be done.

[Brief explanation of drawings]

Figure 1 is an overall configuration diagram of one embodiment of the present invention. Figure 2 is the first embodiment.
Detailed diagram of the control logic circuit in Figure 3.
The figure is a flowchart for explaining the production process shown in FIG. 1...Central processing bag υ', 2...Channel device, 3.
... Input/output control device, 4... Input/output device, 59...
Interface circuit, 6... serial/parallel conversion circuit. 7...Access logic circuit, 8...Control logic circuit. Figure 2

Claims (1)

[Claims] In the input/output control device that connects one or more input/output devices, is connected to a central processing unit via a channel device, and controls the operation of the input/output device according to commands from the central processing unit. a first means for accumulating positioning information of the head of the input/output device specified by a command received from the central processing unit; and positioning of the head of the input/output device based on the positioning information accumulated by the first means. An input/output control device comprising a second means for collectively performing operations.