JPH0786995B2 - Memory control system for cartridge library - Google Patents

Description

The present invention relates to a memory control system of a cartridge library apparatus, and is particularly suitable for guaranteeing memory contents in the event of unexpected power failure, power failure, or the like. The present invention relates to a memory control system for a cartridge library device.

[Prior Art] Generally, a large number of tape cartridges each containing a magnetic tape recording medium are stored in a storage shelf, and a robot device automatically selects an arbitrary cartridge to record / reproduce from the storage shelf. 2. Description of the Related Art Cartridge library devices are known, which are transported to a device and automatically perform recording / reproducing or vice versa. Automatic operation by such a robot device is usually performed by a recording medium (cartridge).
This is realized by referring to / updating the storage position of the storage shelf on the storage shelf, the name of the cartridge (volume serial number VSN ^# ), and the non-volatile memory storing additional information.

Here, as the rewriting data of the non-volatile memory, in addition to the cartridge storage position and the cartridge name,
The location of the cartridge (for example, when the cartridge is taken out by the accessor robot and inserted into the recording / reproducing apparatus, the location is changed as in the cartridge storage shelf → on the accessor robot → recording / reproducing apparatus), the mechanism section (accessor The number of retries of the robot etc. (for example, when the accessor robot takes out the cartridge from the cartridge first, but fails the first time, but succeeds the second time, the number of retries is set to 1 and the life of each mechanical unit or By recording Mitsutent failure data, it will be a guideline for parts replacement and aids in pre-maintenance), command trace (upper level)
For a command received from the CPU, such as a command to insert a cartridge from the storage shelf into the recording / playback device, the time from the time when the command is received to the time when the command ends is recorded as a kind of maintenance information) (These data are collectively referred to as “motion information”). The non-volatile memory is rewritten, for example, when the cartridge is taken in and out (increased / decreased), or when the location of the cartridge is changed as described above.

Therefore, the memory is one of the important elements for operating the cartridge library device of this type correctly, and it is essential to take measures to guarantee the contents of the memory against an unexpected power failure or the like. If such measures are not taken, a memory read error may occur after power is restored, the cartridge cartridge may be returned to the cartridge that has the cartridge, or the cartridge may not be inserted into the recording / reproducing device. There is a risk of uncertainty, which necessitates manual restoration and a huge amount of time and labor.

As a countermeasure against this, conventionally, for example, as disclosed in Japanese Patent Laid-Open No. 62-24465, when a power failure is detected, data indicating the operating state of the cassette storage shelf, the reproducing device, the transporting means, etc. at that time is stored in a memory. A method is known in which, after storing, the contents of the memory are protected by forbidding the writing to the memory by hardware.

[Problems to be Solved by the Invention] Although it is considered that the conventional technology is effective for a power failure or the like in which the voltage drop speed is relatively slow, disconnection at a position immediately before the memory power supply terminal (for example, AC200V / DC5V power supply No consideration is given to the breaker between the memory power supply terminals) and other failures (such as DC breaker disconnection) where the voltage drops sharply.If such a failure occurs, write to the memory. If it is in the middle, it is considered that the writing will be terminated in an incorrect state. Therefore, even after the recovery, the memory contents cannot be correctly referenced and judged, and the read error or the indeterminate contents will not occur until the area is read out later, resulting in the system going down. After all, there was a problem that it took a huge amount of effort and had to be restored.

Therefore, the object of the present invention is to eliminate the above-mentioned problems of the prior art, and to correct the stored contents of the memory (correct the cartridge by the operation of the robot) not only when the power supply voltage drops sharply but also when it suddenly drops. The object of the present invention is to provide a memory control system of a cartridge library device which guarantees instruction control information) for operating in a state.

[Means for Solving the Problems] In order to achieve the above object, a memory control system of a cartridge library apparatus according to the present invention is an accessor for selecting and transporting a cartridge between a storage mechanism for a plurality of cartridges and a recording / reproducing apparatus. Instruct the robot and the operation of this accessor robot (including the operation / state of the cartridge).
Operation information to be controlled (for example, cartridge storage position information, cartridge name, other various additional information described above)
And a non-volatile memory for storing the operation information. When writing new operation information to the memory (when rewriting), the address of the area to be written and the old operation information are temporarily stored. Specific area (11,12)
(The old operation information is read from the area of the memory where the writing is performed and moved to the specific area of the memory), and then the writing is performed.

In addition, after saving the old operation information in a specific area, a memory updating flag (writing flag) is written in a predetermined area (10) on the memory, and then the new information is written in the area indicated by the address. Writing is carried out, and then the memory updating flag is reset (or the memory updating end flag is written in the same area as the memory updating flag). This series of processes can be configured as a subroutine in the program so as to reduce the load on the upper-level program that issues a write instruction.

When the program runs from the beginning when the power is turned on next time, the following processing is performed by the initialization processing or the like. First, the memory-writing flag in the specific area on the memory is read, and if the content is "not writing", normal processing is performed without doing anything to restore the memory. A state in which commands from the CPU can be accepted, a state waiting for processing from the upper CPU, which means a so-called READY state). Also,
If it is "writing", it is determined that the power is cut off during the writing process, and the old data is written and written to the area based on the address and the old data saved in advance. Then, the middle flag is reset to shift to the normal processing. If the "writing" flag does not correspond to a read error or the content is "writing" or "not writing", it is determined that the power was cut off when the "writing" flag was written, and Only the "medium" flag is reset and the normal processing is performed.

It is characterized by the processing at the time of memory writing and the processing at power-on as described above.

[Operation] An operation based on the above configuration will be described.

According to the present invention, when the data is written in the memory for storing the operation information of the accessor robot (when the data is updated),
Since the old data and its address are always saved in a specific area before updating, data may not be written correctly in the memory due to unexpected power failure or sudden voltage drop during updating. Also, it is possible to prevent the destruction and loss of old data and guarantee the memory contents. As a result, when the power is restored, the data on the memory can be returned to the state immediately before the power was cut off.

When writing new data to the memory, after saving the address and old data in a specific area, the memory updating (writing in progress) flag is set, and the instructed data is written in the area indicated by the address. Since it is configured to reset the memory updating flag, by checking the contents of the "memory updating flag" at the next power-on,
It is possible to determine whether or not the memory writing is correctly performed when the power is cut off, and when it is not correctly written, it is possible to restore the state immediately before the power shutdown by a process of returning the old data. Therefore, even if the data is not correctly written in the memory when the power is turned off, the data can be automatically restored when the power is turned on, so that the contents of the memory will not become uncertain.

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

FIG. 1 is a block diagram of a cartridge storage library apparatus according to an embodiment of the present invention, where 1 is a cartridge storage library apparatus, 2 is a high-order CPU, 3 is a magnetic tape controller (MTC), 4 is a library controller (ALC). 5 is a non-volatile memory (LCM, for example, a memory backed up by a battery or a capacitor, which guarantees that stored data will not be lost even in the event of a power failure), 6 is an accessor robot controller (AD
U), 7 are cartridge storage shelves, 8 is an accessor robot (AC), and 9 is a magnetic tape unit (MTU).

When a command to mount the selected cartridge in the cartridge storage shelf 7 to the instructed magnetic tape controller (MTC) 9 is sent from the upper CPU 2 to the library controller (ALC) 4, the ALC 4 is a non-volatile memory. (LCM) 5 is referred to, the cartridge storage position is checked, and a command to mount the MTU 9 is issued to the robot controller (ADU) 6. A
The DU6 activates the accessor robot 8, takes out the cartridge from a predetermined position, and mounts the cartridge on the MTU 9. At the same time, the ALC 4 stores in the LCM 5 additional information and the like that the cartridge is moving. In this way, the state of each cartridge and the state of AC8 are reflected in LCM5 at any time, and the operation continues.

FIG. 2 is a diagram showing the stored contents of the LCM 5 in a simplified manner, and has areas 51 and 52. Area 51 is a cartridge / robot information section that manages the state of the cartridge and accessor robot AC8, and stores the various instruction / control / operation information data described in FIG. 1 and [Prior Art] above. To be done. The area 52 is a data save area provided as a feature of this embodiment, and the data save area 52 is
It has an area 10 for indicating a writing flag (memory updating flag) by a code, an area 11 for saving a writing address, and an area 12 for saving old data. still,
The LCM5 is made nonvolatile by the battery 13. In addition, Fig. 1 shows that ALC4, ADU6, LCM5, MTC3, AC8 are each 1 unit, MTU
9 shows the case of four units, but the number of them is not specified.

Next, a method of controlling the data save area 52 of the LCM 5 will be described.

First, when writing to LCM5, the present contents (old data) indicated by the designated address are read from area 51. Next, the read contents and the designated address are written in the old data save area 12 and the access address save area 11, respectively. After that, a specific code indicating "writing" is written in the writing flag area. Then the area
Write the instructed data (status data of the cartridge, etc.) to the instructed address of 51 and then reset the "writing in progress" flag in area 10 (that is, the end of writing the specific code indicating that writing is not in progress). (Write a signal) to end the series of processes related to writing.
Since this processing is performed every time writing to the memory, the load on the main program may be reduced by implementing it as a subroutine. The unit of data to be rewritten (the amount of data to be written at one time) is for each operation mode.

Next, a process at power-on after power-off will be described.
When the power is turned on, after performing processing such as self-diagnosis of the device, the following processing for LCM5 is performed once.

First, when the writing flag area 10 is read and the content code is "not writing", the process related to LCM5 is not performed. That is, it is determined that the power supply has not been cut off during writing, and the process proceeds to the normal process. Above area
If 10 is "writing", it is determined that the power of the area indicated by the access address save area is cut off during writing, and the contents of the old data save area 12 are written in the area indicated by the address, The writing flag area 10 is reset (returned to the state immediately before the power is cut off), and the processing shifts to the normal processing.

Next, if the contents of the writing flag area 10 is neither "writing" or "not writing", or if a data parity error or the like is detected when reading the area, the "writing flag" is displayed. It is determined that the power supply is cut off during writing, and the area for which writing was planned is not being accessed. Therefore, the "writing flag" is simply reset and the process proceeds to normal processing.

In this way, when writing the LCM5, the old data and the address and the flag indicating whether or not it was being written are stored, so it is possible to determine whether or not the power was cut off in the past when the power was turned on next time. By performing processing such as returning the old data, the contents of the memory can be guaranteed and uncertain data can be eliminated. Therefore, recovery of memory contents by power off, cartridge storage that the robot retains, and MTU9
It is possible to automatically return the remaining cartridges to the storage rack 7 in the system without human intervention.

The present invention can be applied not only to the cartridge library device but also to a system using a non-volatile memory.

In addition, rewriting of new data that could not be written due to power failure etc. is mainly performed under the control of the upper CPU.
Write cartridge name (receive data from CPU, L
In the case of writing data sequentially to CM and writing completion report to CPU), there is no report of if the power is cut off in the middle of, so
After the power is restored, the CPU executes the steps 1 to 3 again. The rest of the data (the location of the cartridge, etc.) is replaced in the library device.

In addition, even if the robot stops in the middle due to a power outage, etc., the sequence up to that point is stored in the non-volatile memory LCM. To be done. Since these matters are not directly related to the present invention, they will not be described in detail.

[Effects of the Invention] As described in detail above, according to the present invention, when rewriting the memory of operation / instruction information such as an accessor robot for controlling selection and transportation of a cartridge, the old information and its address are preserved. Since it is configured to always save in a specific area, if there is a sudden voltage drop due to an unexpected power failure or power failure, of course, DC power failure of the control logic stage, etc.
Even if various failures occur, the contents of this memory can be guaranteed, and as a result, the processing after power-on can be smoothly and automatically performed without confusion or error, and other excellent effects can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a cartridge library apparatus according to an embodiment of the present invention, and FIG. 2 is a diagram showing the contents of a non-volatile memory. 1 ... Cartridge library device, 2 ... Upper CPU,
3 ... Magnetic tape controller, 4 ... Library controller, 5 ... Non-volatile memory, 6 ... Accessor robot controller, 7 ... Cartridge storage rack, 8 ... Accessor robot, 9 ... Magnetic tape Device, 10 ... Writing flag area, 11 ... Access address save area, 12
…… Old data save area, 51 …… Cartridge / robot information area, 52 …… Data save area.

Claims (2)

[Claims] 1. A recording / reproducing apparatus for recording / reproducing data on / from a recording medium stored in a cartridge, a cartridge storage mechanism for storing a plurality of cartridges, and a cartridge storage mechanism selected between the cartridge storage mechanism and the recording / reproducing apparatus. In a cartridge library device having an accessor robot for transporting and a non-volatile memory storing operation information for instructing the operation of the accessor robot, when writing new operation information to the memory, A memory control system for a cartridge library device, characterized in that an address of an area to be written and old operation information are temporarily saved in a specific area and then the writing is performed. 2. When writing the new operation information to the memory, after performing the save, a memory updating flag is further written to the memory, and then the new operation information is written at the address. 2. The memory control system of the cartridge library apparatus according to claim 1, wherein the memory updating flag is reset after writing in the area shown.