JPH0895715A - External storage controller and information processor - Google Patents

Abstract

PURPOSE: To obtain the external storage controller which has a busy state informing means when data stored in the nonvolatile data buffer of a subsystem contains data that should not be erased as a result of power-off operation or when an external storage device is in operation and to prevent a nonvolatile data buffer from being erased by inhibiting the power source from being turned off on receiving busy state information and displaying that on a display device. CONSTITUTION: A main system 60 and the subsystem 62 having a sub-CPU 42, the nonvolatile buffer memory 44 which stores data that should not be erased as a result of power-off operation, etc., the nonvolatile external storage device 48 having a busy output 52, the external storage controller 56 having the busy state informing means 58, etc., are connected through an interface 40; and the main system is prevented from being powered off with a cache busy signal 58.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an external storage control device applied to an information processing device such as a disk cache system and an information processing device having the same.

[0002]

2. Description of the Related Art FIG. 3 shows a disk cache system as an example of prior art.

The main system 160 is a main CPU 1
20, main memory 122, I / O device 124, I / O device 126, system bus 128, LED 132, power supply 13
6 and the like, performs data processing and the like, and as one operation thereof, transmits and receives commands and data to and from the HDD I / F subsystem 162 connected via the bus interface 140. The HDD I / F subsystem 162 includes a sub CPU 142 and a buffer memory 14.
4, HDD controller 146, HDD 148, internal bus 150, HDD busy signal 152, etc.
Data from the DD 148 is stored in the buffer memory 144, that is, cache, and data from the main system 160 is stored in the buffer memory 144, that is, write buffering is performed.

The HDD I / F subsystem 162 is an H
During the data read operation or the write operation for the DD 148, the HDD busy signal 152 is output from the HDD 148 to indicate the operation to the main system 160. HDD
The busy signal 152 indicates that the HDD 148 is operating visually or by means of an LED or the like in the main system 160.

[0005]

For example, in the disk cache system as shown in FIG. 3, the HDD 14
8 is being accessed, or when the data that should be written to the HDD 148 exists in the buffer memory 144 and the main system 160 is powered off, the content data of the HDD 148 is not the data to be written. This leads to the destruction of content data such as loss of valid data.

While accessing the HDD 148, the LED 1
It is possible to recognize that the access is being made by turning on 32, but if the power is accidentally turned off during the access, the content data will be destroyed.

While accessing the HDD 148, the LED 1
Although it is possible to recognize that the data is being accessed by turning on 32, there is no recognition method when there is data that should not be erased in the buffer memory 44.

Further, in order to turn off the power, the data which must be written in the HDD 148 is the buffer memory 1
44, the sub CPU 142 detects a power-off request from the main system 160,
All valid data of 44 must be written in the HDD 148, and then the HDD I / F subsystem 162 must perform complicated control and processing such as allowing the main system 160 to turn off the power.

The present invention prevents the main system from being powered off when data protection is required in the subsystem regardless of when the main system is powered off. The purpose is to prevent actions that lead to destruction.

[0010]

A main system having a first CPU, a non-volatile external storage device having a second CPU, a volatile buffer memory, and a busy output, and a busy notifying means for the first main system. And a subsystem capable of transmitting and receiving commands, data, etc. through an interface with the main system, and the data stored in the volatile buffer memory The external storage control device including the data that should not be erased and having the busy notification means of the subsystem, when there is data that should not be erased in the volatile buffer memory for the main system, or When the non-volatile external storage device is in operation, it notifies busy to the main system. That the external storage controller.

In the above external storage control device, when there is data that should not be erased in the buffer memory due to the busy notification of the external storage control device described above, or the external storage device is operating. An external storage control device, which notifies the power supply of prohibition of power-off at the time of.

In the above external storage control device, when there is data that should not be erased in the buffer memory due to the busy notification of the external storage control device described above, or the external storage device is operating. The external storage control device is characterized in that it is displayed on the display device at the time of, and that the latest valid data is visually not written back to the external storage device.

In the external storage control device described above, the busy notification signal of the external storage device described above is replaced with the busy notification signal of the nonvolatile external storage control device described above, and the main system and the An external storage controller capable of replacing the interface signal between the described subsystems with an interface signal of an external storage device, and being able to mount the external storage controller on a system not equipped with a conventional external storage controller. .

An information processing device having the above-mentioned external storage control device.

[0015]

1 is a block diagram showing the configuration of an information processing apparatus according to an embodiment of the present invention. Main CPU 20,
Main memory 22, system bus 28 including address and data and various control signals, and data exchange with the outside I
Controller 3 that generates an LED lighting signal 34 and a power-off prohibition signal 38 from a cache busy signal 58 of the I / O device 24, the I / O device 26, and the HDD I / F subsystem 62.
0, LED3 which visually indicates the cache busy of HDD I / F subsystem 62 from LED lighting signal 34
2. The main system 60 configured by the power supply 36 and the like that can recognize the power-off prohibition signal 38 and the data that cannot be erased in the buffer memory 44 of the HDD I / F subsystem 62 and control the power-off prohibition As one of the I / O devices of the main system 60, as an external storage for the main system 60 and a subsystem for performing data caching.
A DD I / F subsystem 62 exists and supports data transfer between the main system 60 and the external storage device HDD 48. The HDD I / F subsystem 62 exchanges commands and data with the main system 60 via the bus interface 40, accesses the HDD 48 in accordance with an operation request from the main system 60, and the HDD 4
Sub CPU 42, H for controlling the caching of 8 data
Cache data from DD48 and main system 60
Buffer memory 44 for temporarily storing the write data to be written from the HDD 48 to the HDD 48, the sub CPU 42 to the HDD 4
8, an HDD controller 46 for passing commands to the HDD, an external storage device HDD 48, an internal bus 50 including addresses, data and various control signals, an HDD busy signal 52 indicating that the HDD 48 is operating, and a cache / busy controller 56. To be done. Its main function is to control the HDD 48 in accordance with a request from the main system 60, and in the case of a read or write operation of the main system 60, read from the volatile buffer memory 44 from the external storage device HDD 48 or to the volatile buffer 44. By utilizing the fact that writing is faster in time, the disk cache system controls caching of read data from the HDD 48, buffering of write data from the main system 60 to the HDD 48, and reading or writing to the HDD 48 as a system. It realizes high-speed data processing.

The latest write data from the main system 60 to the HDD 48 is buffered by the write command in the buffer memory 44 to end the write command, and after the write command is completed, the main system 60 and the HDD I / F subsystem 62 by the bus interface 40. And the buffer memory 44 is separated by the sub CPU 42.
It is written to the HDD 48 via the HDD controller 46. Main system 60 has power supply 36, HD
The power supply of the D I / F subsystem 62 is the main system 6
If it is supplied from 0, when the latest write data exists in the volatile buffer memory 44 and the power supply 36 of the main system 60 is turned off, the buffer memory 44
The latest data of is deleted without being written back to the external storage HDD 48. Therefore, when the latest write data is written from the main system 60 to the buffer memory 44, the sub CPU 42 will receive the cache busy signal 5
8 is asserted and generated by the control device 56, the main system 60 is informed that the latest valid data exists in the buffer memory 44, and the main system 60 sends the HDD
After the write command to the I / F subsystem 62 is completed, the data buffered in the buffer memory 44 is transferred to the external storage device HDD via the HDD controller 46.
Write back to 48. If the latest valid data does not exist in the write buffer and the access to the HDD 48 is not busy, the cache busy signal 58 is negated. The controller 30 of the main system 60, which is notified by the cache busy signal 58 that the latest valid data exists in the buffer memory 44, receives the power-off prohibition signal 38.
Is asserted to prevent power-off of the power supply 36 and prevent operations such as loss of valid data leading to destruction of content data.
The case where data protection of the volatile data buffer is required is visually shown by asserting the ED lighting signal 34 and lighting the LED 32.

FIG. 2 shows the control device 3 in the embodiment of FIG.
3 is a circuit block diagram showing a detailed configuration of 0 and a control device 56. FIG. When data is written from the main system 60 to the HDD I / F subsystem 62, the cache busy controller 56, when the sub CPU 42 monitors the bus interface 40 and detects a write data command, volatiles the latest valid data. When writing to the buffer memory 44, the write buffer busy flag flip-flop 70 which is "L" at the time of assertion and the data bus signal 72 which is the data signal of the write buffer busy flag flip-flop are "L". Then light
When the write signal 74 of the buffer busy flag flip-flop is set to "HLH", the write buffer is set to "H" at RESET, "L" when asserted, and "H" when negated.
The busy signal 76 is asserted, and the write buffer busy signal and the HDD busy signal 52 are "L" signals when asserted, and the cache busy signal 58 of "L" is generated at the time of assertion via the AND 78, and the latest valid data is generated. When it exists in the volatile buffer memory 44, or the HDD 4
When the access to 8 is busy, the cache busy signal 58 is asserted, and the main system 6 is set to "L".
Notify the control device 30 of 0. After asserting the write buffer busy flag flip-flop, the sub CPU 42 causes the volatile buffer memory 44 to perform a data write operation from the main system 60, and monitors the bus interface 40 from the main system 60. If a data write command does not occur within a fixed time after the completion of the series of data write commands, the bus interface 40 is disconnected from the main system 60, and the latest valid data written in the volatile buffer memory 44 is set to H level.
The latest valid data in the volatile buffer memory 44 is written in the nonvolatile external storage device HDD 48 via the DD controller 46 and the internal bus 54, and the latest valid data is stored in the nonvolatile external storage device H.
Since the write buffer busy flag flip-flop 70 is also present in the DD 48, the write buffer busy flag flip-flop 70 sets the data bus 72 to "H" as the data signal of the write buffer busy flag flip-flop, and the write buffer
Busy flag flip-flop write signal 74
Is set to "HLH" and the write buffer busy signal 7
Negate 6. When the latest valid data from the cache busy signal 58 exists in the buffer memory 44, or when the access to the HDD 48 is busy, the control device 30 is notified to the power supply 36 that the power supply 36 is "L". When the disconnection prohibition signal 38 is asserted to prohibit the power supply from being cut off to the power supply 36, and when the LED 32 is asserted, the "L" LED lighting signal 34 is asserted to protect the volatile data buffer. Show visually. When the power-off prohibition signal 38 is asserted and the power-off prohibition is notified, the power supply 36 does not perform the power-off operation even if the power-off operation is performed, and the power-off prohibition signal 38 is negated to notify the power-off permission. Power off operation is performed when the

When the main system 60 performs the read operation, if the data to be read is the buffer memory 44.
If the data to be read does not exist in the buffer memory 44, the external storage device HDD 48 writes the data in the buffer memory 44 via the internal bus 54 and the HDD controller 46. At the same time, it is read into the main system 60 via the bus interface 40. At this time, since the latest valid data exists in the HDD 48, the write buffer busy flag 70 is not asserted, and the HDD busy signal 5 indicating that the HDD 48 is operating
The cache busy signal 58 is asserted when 2 is asserted.

By replacing the cache busy signal 58 output from the external storage controller with the HDD busy output signal 52 from the external storage controller, the signal terminal of the bus interface 40 is replaced with the signal terminal of the internal bus 54 of the external storage device. Therefore, the conventional HDD interface without the external storage controller of this embodiment, that is, the conventional HDD control signal can be used as it is to connect the external storage controller. Specifically, in FIG. 1, a signal equivalent to the HDD busy output signal 52 is output from the bus interface 40 to the main system 60 via the internal bus 54 and the internal bus 50. A signal equivalent to this HDD busy signal is also output to the conventional interface 140 of FIG. Therefore, write to the HDD busy output signal on the bus interface 40
If the buffer busy signal 76 is connected in the same manner as in FIG.
The buffer memory 44 can be controlled while using the HDD interface compatible with the conventional one.

In this embodiment, if the main system only has a power source, that is, the power of the subsystem is supplied from the main system, the main system and the subsystem may have independent power sources,
You may have one of them. Although the HDD is used as the external storage device in the embodiment, an external storage device such as a floppy disk drive or a magneto-optical storage device is also applicable. Although the display means is shown by the LED, a display device such as a buzzer or a monitor display device is also applicable, and although the display means such as the LED is only provided in the main system in this embodiment, an independent display device is provided for each of the main system and the sub system. You may have it in the system or in either one.

As described above, according to this embodiment, when the data in the volatile data buffer of the subsystem needs to be protected regardless of the power-off of the main system, the cache busy from the subsystem is performed. When a power supply receives a busy notification, it prohibits power-off to prevent operations that lead to the destruction of contents data such as loss of valid data, and when data protection of the volatile data buffer is required. It is possible to easily show things visually.

[0022]

As described above, the present invention provides a busy notification by the external storage control device of the subsystem when it is necessary to protect the data in the volatile data buffer of the subsystem regardless of the power-off of the main system. By doing so, prohibit operations that lead to the destruction of the contents data such as prohibiting power-off or loss of valid data, and visually indicating when data protection of the volatile data buffer is required, etc. To realize. Also, by replacing the busy notification output of the external storage device with the busy notification output of the external storage control device,
This external storage control device can be easily installed in a system having a conventional external storage device interface.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of an information processing apparatus according to an embodiment of the present invention.

FIG. 2 is a circuit block diagram showing a detailed configuration of a control device 30 and a control device 56 in the embodiment of FIG.

FIG. 3 is a block diagram showing a configuration of a conventional information processing apparatus related to one embodiment of the present invention.

[Explanation of symbols]

 20-main CPU 22-main memory 24-I / O device 26-I / O device 28-system bus 30-control device 32-LED 34-LED lighting signal 36-power supply 38-power-off prohibition signal 40-bus interface 42 -Sub CPU 44-Buffer memory 46-HDD controller 48-HDD 50-Internal bus 52-HDD busy signal 54-Internal bus 56-Control device 58-Cache busy signal 60-Main system 62-HDD I / F subsystem 70 -Write buffer busy flag 72-Data bus signal 74-Write signal 76-Write buffer busy signal 78-AND 80-Buffer 82-Buffer 120-Main CPU 122-Main memory 124-I / O device 126 -I / O device 128-System bus 1 2-LED 136- power 140- bus interface 142 - sub CPU 144-buffer memory 146-HDD controller 148-HDD 150- internal bus 152-HDD busy signal 154- internal bus 160- main system 162-HDD I / F subsystem

Claims (5)

[Claims] 1. A main system having a first CPU, a non-volatile external storage device having a second CPU, a volatile buffer memory and a busy output, and an external storage having a busy notification means for the first main system. It is composed of a subsystem that is capable of transmitting and receiving commands, data, etc. through an interface with the main system, which is composed of a control device, and the data accumulated in the volatile buffer memory should not be erased by power-off or the like. The external storage control device including the data that cannot be erased and having the busy notification means of the subsystem, when there is data that should not be erased in the volatile buffer memory, or when the nonvolatile external storage device is operating. An external storage control device, which notifies the main system of busy. 2. The external storage control device according to claim 1, wherein when there is busy notification of the external storage control device described above, and there is data that should not be erased in the buffer memory, or An external storage control device, which notifies the power supply to prohibit power-off when the external storage device is in operation. 3. The external storage control device according to claim 1, when a busy notification of the external storage control device described above is received, and there is data that should not be erased in the buffer memory, or An external storage control device, which displays on the display device when the external storage device is in operation, and visually indicates that the latest valid data has not been written back to the external storage device. 4. The external storage control device according to claim 1, wherein the busy notification signal of the external storage device is replaced with the busy notification signal of the nonvolatile external storage control device for output. An external storage control device characterized by the above. 5. A main system having a first CPU, a non-volatile external storage device having a second CPU, a volatile buffer memory and a busy output, and an external storage having a busy notification means for the first main system. It is composed of a subsystem that is capable of transmitting and receiving commands, data, etc. through an interface with the main system, which is composed of a control device, and the data accumulated in the volatile buffer memory should not be erased by power-off or the like. The external storage control device including the data that cannot be erased and having the busy notification means of the subsystem, when there is data that should not be erased in the volatile buffer memory, or when the nonvolatile external storage device is operating. , Information processing comprising an external storage controller characterized by notifying the main system of busy Location.