JPH08227386A - Peripheral device - Google Patents

Abstract

PURPOSE: To maintain the performance of the whole system by suppressing the load of a host computer to a minimum level at the occurance of abnormality. CONSTITUTION: This peripheral device is provided with a controller 3 for receiving a command from a host computer 1, analyzing the command and outputting an instruction signal and processors 4, 5 connected to the controller 3 and allowed to execute prescribed processing based upon the instruction signal outputted from the controller 3. At the time of detecting the abnormal operation of the processor 4 or 5, the controller 3 informs the abnormal end of the command to the host computer 1 and outputs a signal for applying the same instruction as said instruction signal to the processor 4 or 5 of which abnormal operation is detected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a peripheral device connected to a computer or the like.

[0002]

2. Description of the Related Art In recent years, with the advent of multimedia, various peripheral devices have been connected to one host computer through various interfaces. Along with this, the load on the control of the peripheral device of the host computer is increasing. If the host computer sends a command to the peripheral device and receives a report that the command was not successfully received by the peripheral device, the host computer sends the same command again and causes the peripheral device to perform retry processing. It was

However, since various peripheral devices are connected to the host computer, another peripheral device may receive another command during the abnormal termination of the command, and then another device may retry the process. In many cases, another command must be executed for the peripheral device. Moreover, it is necessary to perform internal processing of the computer such as calculation. Therefore, there is a considerable time lag between the host computer receiving the abnormal termination report and the command re-execution.

Conventionally, the peripheral device waits for the next command from the host computer after reporting the abnormal termination of the command to the host computer, and then receives the command for re-execution and then performs the retry process. It was

[0005]

However, if the peripheral device retries after receiving the re-execution command, the host computer takes a long time to control the peripheral device. As a result, other peripheral devices are kept waiting during that time. In addition, the internal processing of the host computer such as calculation is also hindered, resulting in a serious decrease in performance of the entire system.

It is an object of the present invention to provide a peripheral device capable of minimizing the load on the host computer and maintaining the performance of the entire system when an abnormality occurs.

[0007]

[Means for Solving the Problems] In order to solve the above problems,
The peripheral device of the present invention receives a command from the host computer, is connected to the controller that outputs an instruction signal by analyzing the command, and is connected to the controller, and performs predetermined processing according to the instruction signal from the controller. And a processing device that performs
When an abnormal operation of the processing device is detected, an abnormal end of the command is reported to the host computer, and the same instruction as the instruction signal is given to the processing device in which the abnormal operation is detected. It is configured to output a signal.

The controller has a storage means for storing the command and a processing result of the command. When the same command is received again from the host computer, the processing result stored in the storage means is stored in the host. It is preferable that the data is transmitted to a computer.

[0009]

According to the present invention, when an abnormality occurs in the peripheral device, the retry process is performed while the host computer is communicating with another peripheral device or while performing internal processing such as calculation in the computer. A controller within the device can be used. The controller reports the result of the retry process in response to the re-execution command from the host computer. An example of the peripheral device is an external storage device such as a disk drive device.

[0010]

1 is a block diagram showing the configuration of a peripheral device according to an embodiment of the present invention. In the present embodiment, an example in which a storage device for storing information in a recording medium such as a magnetic disk or an optical disk is used as a peripheral device will be described.
In FIG. 1, the storage device 2 is connected to the host computer 1 via a SCSI bus. The storage device 2 is
It is composed of one controller 3 and two drive devices 4 and 5. Drive device 4 and drive device 5
Is a so-called disk drive device. For example,
When a command for recording data is sent from the host computer 1 to the storage device 2, the controller 3 analyzes the command and outputs the data to be recorded to the storage device 2.
Drive device 4, 5 together with instruction information for recording each piece of data to be recorded on a recording disk.
Send to Each of the drive devices 4 and 5 performs a process of recording the sent data on a recording disk. In this way, the data to be recorded sent from the host computer 1 is divided and stored in the two drive devices 4 and 5.

When a command for reading the data recorded on the recording disk of each drive device is sent from the host computer 1 to the storage device 2, the controller 3 receives the command, and the drive device 4 and the drive device 5 are received.
Issue a read operation instruction to. At this time, the address (logical address) data of the data to be read is added to the read command from the host computer 1. The controller 3 converts the sent address into a physical address (address indicating an actual recording position on the recording disk in the two drive devices). In this device, the data sent from the host computer 1 is divided into two, and the respective data are stored in the drive device 4 and the drive device 5. Therefore, the physical address is indicated by the address of the drive device and the address of the recording area on the disc in the drive device.

The controller 3 sends instruction information to each drive device to read the data recorded in a predetermined address area. The controller 3 synthesizes the data read from each of the drive device 4 and the drive device 5, and sends it to the host computer 1 as read data. Now, it is assumed that the controller 3 detects from the report from the drive device 4 that the read operation of the drive device 4 is abnormal. It is assumed that the data can be normally read from the drive device 5. The controller 3 stores the command received from the host computer 1 and the data read from the drive device 5 in the built-in RAM 6.
Then, the abnormal termination of the command is reported to the host computer 1.

After that, the controller 3 drives the drive unit 4
Again, the read operation instruction is issued. Controller 3
When the read operation of 1 is normally performed, the controller 3 stores the data read from the drive device 4 in the RAM 6. If the read operation of the controller 3 is again abnormal, a flag indicating the abnormal end is set in the RAM 6
To memorize.

When a command is sent again from the host computer 1 to the storage device, the controller 3
Compares whether the received command is the same as the command stored in the RAM 6. If different, the command is analyzed as usual and the drive device 4 and the drive device 5 are instructed to operate. If they are the same, since it is a command sent to the storage device 2 to perform a retry, it is checked whether or not a flag for notifying the abnormal end is stored in the RAM 6. If it is stored, the abnormal termination of the command is reported to the host computer. If it is not stored, the data read from the respective drive devices of the drive device 4 and the drive device 5 are taken out from the RAM 6, combined, and sent to the host computer 1.

Although two drive devices are used as the processing devices connected to the controller 3 in this embodiment, the number of the processing devices connected may be one, or three or more. May be.

[0016]

As described above, according to the present invention, it is possible to perform retry processing when an abnormality occurs in a peripheral device without the intervention of a host computer, so that it is possible to prevent the system performance from being deteriorated. it can.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a peripheral device and a system according to an embodiment of the present invention.

[Explanation of symbols]

 1 Host computer 2 Storage device 3 Controller 4, 5 Drive device 5 RAM

Claims (2)

[Claims] 1. A controller which receives a command from a host computer and outputs an instruction signal by analyzing the command, and a process which is connected to the controller and performs a predetermined process in response to the instruction signal from the controller. A device, the controller, when detecting an abnormal operation of the processing device, while reporting an abnormal end of the command to the host computer, to the processing device in which the abnormal operation is detected, A peripheral device, which outputs a signal for giving the same instruction as the instruction signal. 2. The controller has a storage means for storing the command and a processing result of the command, and when the same command is received again from the host computer, the processing result stored in the storage means. Is transmitted to the host computer.