JPH07287919A - Disk takeout control method - Google Patents

Abstract

PURPOSE:To prevent the trouble of a host system and the damage of a recorded file by making a specified time from the time of inputting a disk takeout requesting signal a waiting time and controlling a disk takeout in accordance with the presence or absence of the command from the host system during this time. CONSTITUTION:When the disk takeout requesting signal is supplied from a takeout request detecting means 5 by operating a switch SW, a CPU 4 sets the waiting time of a specified time from this point of time via a time measuring means 7. Then, the CPU 4 executes a takeout at the time when the command from the host system is not present, and at the time when the command is present, the disk takeout operation is stopped during a command execution by the CPU 4. Thus, even in the case where the erroneous operation of an operator concerning the disk takeout request is present, the generations of the trouble of the host system and the damage of the recorded file, etc., are prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disc ejection control method for ejecting an optical disc or a magnetic disc loaded in a disc drive device from the device.

[0002]

2. Description of the Related Art A disk drive device in which a disk-shaped disk is used as a recording medium and information is read or written by a disk head while the disk is rotated at a high speed on a rotary table is practically used as an external storage device of a computer. ing. It is well known that this disc drive device can mount and remove a required disc as needed. Conventionally, when the disc mounted on the rotary table is taken out, the central processing unit issues a take-out command signal in response to an operator's take-out request, and the disc taking-out means which receives the command signal takes the disc on the turntable to the outside of the apparatus. The procedure was to discharge.

[0003]

Now, while the disk drive device is executing the drive operation, it is prohibited for the operator to request the removal of the disk. what if,
Even if the central processing unit receives a disc ejection request due to an erroneous operation or the like, it is programmed to prohibit the disc ejection until the drive operation is completed.

However, the conventional disk drive device is
The host system does not have the function of monitoring the series of commands that it is trying to process. Therefore, if a disk eject request is received before a command group is sent from the host system, the disk eject operation will continue. There was a risk that it would be executed. In this way, if the disk eject operation is executed before the host system finishes the scheduled command processing, there arises inconvenience such as damage to the file to be written to the disk.

For example, computer systems using a disk cache are increasing in order to improve the file writing performance from the host system. When this disk cache is performed by the write-back method, the information from the host system is first registered in the cache memory, and then the information is written from the cache memory to the disk. However, if the disk is taken out before writing the information registered in the cache memory, the information file may be lost.

Further, when a disk drive is used as a substitute for a fixed magnetic disk device (HDD), the application software often does not support disk replacement, and if the disk is replaced while the host system is operating, the application software will not be replaced. Could stop or lead to storage file damage.

The present invention has been made in view of the above circumstances, and automatically prohibits the disc ejection operation which is inconvenient in relation to the host system, even if the operator makes an erroneous operation regarding the disc ejection request. , The purpose is to effectively prevent the trouble of the host system and the damage of the recording file.

[0008]

In order to achieve the above-mentioned object, a first aspect of the invention is to set a certain waiting time after inputting a disk ejection request signal, and to issue a command from a host system within the waiting time. When the command is input from the host system during the above waiting time, the disk ejection operation must be stopped at least while the command is executed. It has a feature.

A second aspect of the invention is characterized in that the disc ejecting operation is executed when the disc ejecting request signal is continuously input for a certain period of time. A third aspect of the present invention sets a certain waiting time after inputting a disc ejection request signal, and when the disc ejection request signal is input a predetermined number of times or a predetermined number of times or more within the waiting time, the disc ejection operation is performed. It is characterized by executing.

A fourth aspect of the invention is to set a fixed waiting time after inputting a disc take-out request signal, do not input a command from the host system within the waiting time, and keep the disc take-out request signal for a given time. It is characterized in that the disc ejecting operation is executed when the input is made.

A fifth aspect of the invention is to set a fixed waiting time after inputting a disc take-out request signal, do not input a command from the host system within the waiting time, and set a fixed time same as or different from the waiting time. It is characterized in that the disk ejecting operation is executed when a disk ejecting request signal is input a predetermined number of times or more than a predetermined number of times within the waiting time.

[0012]

It is assumed that the host system receives a disk eject request before processing a scheduled command due to an erroneous operation by the operator. In the first invention, after receiving the eject request signal, A certain waiting time is set before execution of the take-out operation. It is preferable that the waiting time is longer than the time when a command is expected to be input from the host system.

For example, in the write-back type disk cache, the time from when the host system registers in the cache memory to when the write command is output from the host system is within 0.5 to 1 second. Therefore, in order to prohibit the disk ejection operation which is inconvenient in the disk cache, 0.
A standby time of about 5 to 1 second may be set. For safety, it is preferable to set a longer time,
If the waiting time becomes too long, there is an adverse effect that the speed of processing is lost.

When a command is input from the host system during the waiting time, the disk ejection is prohibited and the command processing is executed. On the other hand, when no command is input from the host system during the waiting time, the disk eject operation is executed.

The second invention and the third invention are, for example, a fixed magnetic disk device (H) when the disk drive device and the host system have a special connection relationship.
When using a disk drive as an alternative to DD),
It is assumed that a person who does not know the relationship may erroneously make a request to take out a harmful disk. That is, in each of the inventions, the disc ejecting operation is executed only when the disc ejecting request signal is received in a special mode so that a person who does not know the mode cannot take out the disc.

Specifically, the disc ejection request signal is continuously input for a fixed time (second invention), or the disc ejection request signal must be input a predetermined number of times or a predetermined number of times or more within the fixed time (first). Third invention), the disk ejecting operation cannot be executed, which prevents troubles of the host system and damages of storage files due to erroneous operations.

The fourth invention and the fifth invention combine the above-mentioned first invention with the second or third invention so that the disk before processing the command scheduled by the host system is processed. Ejection and removal of a disc that has a harmful effect when the disc drive device and the host system have a special connection relationship are prohibited.

[0018]

Embodiments of the present invention will be described below in detail with reference to the drawings. In addition, the following embodiments will be described for an optical disk drive device. FIG. 1 is a block diagram showing an optical disk drive device for implementing a disk control method according to an embodiment of the present invention. This optical disk drive device includes an I / F control unit 1, a data processing unit 2, an R / W control unit 3, a central processing unit (CPU) 4, a take-out request detection unit 5, an optical disc take-out unit 6, and a clocking unit 7. There is.

The I / F control unit 1 is a component connected to the host system and for exchanging commands and data with the host computer. The I / F control unit 1 is configured based on the well-known SCSI and IDE / ATA standards. The data processing unit 2 performs error correction, modulation and demodulation of the data signal input from the host system or the data signal read from the optical disc. The R / W control unit 3 controls the optical head and also controls the I / F control unit 1.
And a component for recording the data signal from the host computer input through the data processing unit 2 on the optical disc and reading the data of the optical disc. As the optical disk, a writable and readable optical disk of, for example, a magneto-optical system or a phase change system is used.

The central processing unit 4 controls each component of the optical disk drive device. The take-out request detecting means 5 is a component that detects a take-out request of an optical disk by an operator, and turns ON / OFF a switch SW such as a micro switch, a touch switch, or an optical switch provided on the surface panel of the optical disk drive device. To detect.
That is, the operator makes a request to take out the optical disk by turning on the switch SW, and the means turns on.
The operation is detected, and the extraction request signal is output to the central processing unit 4.

The optical disc take-out means 6 is a component for ejecting the optical disc based on the optical disc take-out command signal from the central processing unit 4, and is provided with a motor and a solenoid as a drive source for ejecting. The clock means 7 is a timer that counts a predetermined clock.

2 and 3 are flow charts showing an optical disk ejection control method according to the first embodiment of the present invention. When the operator turns on the switch SW to request the ejection of the optical disk, the ejection request detection means 5 detects this and outputs an ejection request signal to the central processing unit 4. When the extraction request signal is input, the central processing unit 4 sets an extraction request flag as shown in FIG. When waiting for a command from the host system, the central processing unit checks whether or not there is a fetch request flag, and when it detects this flag, it executes the fetch control flow shown in FIG.

The central processing unit 4 first issues a start command to the timing means 7 to count the elapsed time from the time when the take-out request flag is detected. The time information obtained by the time measuring means 7 is output to the central processing unit 4. Then, the central processing unit 4 stands by without performing the operation of taking out the optical disc while the preset fixed time has elapsed. When a command is received from the host system during the waiting time, the time measuring means 7 is executed without executing the operation of taking out the optical disk.
The counting of the elapsed time is stopped, the take-out request flag is cleared, and the take-out operation control ends. The central processing unit which has completed the take-out operation in this way continues to execute the command received from the host system.

On the other hand, if no command is received from the host system during the waiting time, the central processing unit 4 issues a take-out command to the optical disc take-out means 6 to execute the optical disc take-out operation. Then, after the take-out operation is completed or in parallel with the take-out operation, the counting of the elapsed time by the timer 7 is stopped, the take-out request flag is cleared, and the take-out operation control is ended.

FIG. 4 is a flow chart showing an optical disk ejection control method according to the second embodiment of the present invention. In the first embodiment described above, when a command is received from the host system during a certain waiting time, the operation of ejecting the optical disc is stopped regardless of the type of the command. However, in the connection between the host system and the optical disk drive device, a particular problem is that when the information from the host system is written to the optical disk by using the write-back type disk cache, the optical disk is written before the write command processing. It's time to take out. In this case, the file registered in the cache memory may be damaged.

Therefore, particularly in this embodiment, the optical disk take-out operation is canceled only when the write command is received during the waiting time. That is, after the extraction request flag is set as in the first embodiment, the extraction control flow shown in FIG. 4 is executed.
In the flow, first, it is confirmed whether or not the timekeeping means 7 is operating, and if not, the timekeeping means 7 is operated and the elapsed time is counted. Then, it waits until a certain period of time elapses, and monitors whether or not a command is received from the host system during that time. When a command is received from the host system during the standby time, it is further determined whether or not the command is a write command, and if it is a write command, the time counting means 7 is executed without executing the optical disc ejecting operation. The counting of the elapsed time is stopped, the take-out request flag is cleared, and the take-out operation control ends.

The central processing unit, which has completed the take-out operation as described above, proceeds to execute the write command received from the host system, issues a write command to the R / W control unit 3, and writes the information from the host system to the optical disc. Write. On the other hand, if the received command is not a write command, the received command is processed while the fetch request flag in FIG. 2 is set, the fetch request flag is detected again, and the fetch control flow shown in FIG. To start. At this time, since the elapsed time has already been counted by the time counting means 7, it stands by and waits for a command from the host system.

When no command is received from the host system until a certain waiting time elapses, the central processing unit 4 issues an eject command to the optical disc ejecting means 6 to execute the optical disc ejecting operation. After the take-out operation is completed or in parallel with the take-out operation, the counting of the elapsed time by the time counting means 7 is stopped, and
The take-out request flag is cleared and the take-out operation control ends.

FIG. 5 is a flow chart showing an optical disk ejection control method according to the third embodiment of the present invention. In this embodiment, when the optical disk drive device and the host system have a special connection relationship such as the case where the optical disk drive is used as a substitute for the fixed magnetic disk device (HDD), the relationship is known. This is intended to prevent a person who does not make a mistake by making a request for taking out an optical disk having a harmful effect.

That is, when the operator turns on the switch SW to request the ejection of the optical disk, the ejection request detecting means 5 detects this and outputs an ejection request signal to the central processing unit 4. Here, the switch SW is continuously in the ON state while the operator is pressing the switch button, and during this ON state, the take-out request detecting means 5
Continues to output the fetch request signal to the central processing unit 4.

When the central processing unit 4 receives the extraction request signal, it sets the extraction request flag as shown in FIG. 2 and executes the extraction control flow shown in FIG. The central processing unit 4 first issues a start command to the time measuring means 7 and causes the elapsed time from the time of detection of the take-out request flag to be counted.
The time information obtained by the time measuring means 7 is output to the central processing unit 4. Then, the central processing unit 4 stands by without performing the operation of taking out the optical disc while the preset fixed time has elapsed.

During the waiting time, the retrieval request detecting means 5
If the take-out request signal is continuously output from the central processing unit 4, the central processing unit 4 issues a take-out command to the optical disc taking-out means 6 to execute the optical disc taking-out operation. Then, after the take-out operation is completed or in parallel with the take-out operation, the counting of the elapsed time by the timer 7 is stopped, the take-out request flag is cleared, and the take-out operation control is ended. On the other hand, when the take-out request signal from the take-out request detecting means 5 is interrupted at the time of counting the time by the time-measuring means 7 or in the middle of the waiting time, the elapsed time by the time-measuring means 7 is not executed without performing the operation of taking out the optical disk. And the removal request flag is cleared, and the removal operation control ends.

If only a specific person who operates the optical disk drive device is informed that such an operation method, that is, that the switch SW must be kept pressed for a certain period of time to take out the optical disk, another unspecified person However, even if the user tries to eject the optical disk without knowing this operation method, all of them are canceled, so that an accident such as file damage can be prevented.

FIG. 6 is a flow chart showing an optical disk ejection control method according to the fourth embodiment of the present invention. Similar to the third embodiment, this embodiment also has a special connection relationship between the optical disk drive device and the host system when the optical disk drive is used as a substitute for the fixed magnetic disk device (HDD). In this case, the purpose is to prevent a person who does not know the relationship from erroneously making a request for taking out a harmful optical disk.

That is, when the operator turns on the switch SW to request the ejection of the optical disc, the ejection request detecting means 5 detects this and outputs an ejection request signal to the central processing unit 4. When the extraction request signal is input, the central processing unit 4 sets the extraction request flag as shown in FIG. 7, counts the number of extraction requests to 1, and executes the extraction control flow shown in FIG.

The central processing unit 4 first issues a start command to the time measuring means 7 and causes it to count the elapsed time from the detection of the take-out request flag. The time information obtained by the time measuring means 7 is output to the central processing unit 4. Then, the central processing unit 4 stands by without performing the operation of taking out the optical disc while the preset fixed time has elapsed. When the operator turns on the switch SW again during this waiting time, the take-out request detecting means 5 detects this and outputs a take-out request signal to the central processing unit 4. At this time, since the fetch request flag has already been set, the central processing unit 4 adds 1 to the fetch request count as shown in FIG. That is, the number of retrieval requests is recorded as 2 here.

When a certain waiting time has elapsed, the central processing unit 4 confirms the number of ejection requests, and if two ejection requests are made, the central processing unit 4 instructs the optical disc ejecting means 6 to eject. Is issued, and the operation for taking out the optical disk is executed. Then, after the take-out operation is completed or in parallel with the take-out operation, the counting of the elapsed time by the timer 7 is stopped, the take-out request flag is cleared, and the take-out operation control is ended.

On the other hand, if the eject request is not made twice, the counting of the elapsed time by the time counting means 7 is stopped and the eject request flag is cleared without executing the eject operation of the optical disk. The take-out operation control ends. If only the specific person who operates the optical disk drive device knows such an operation method, that is, that the switch SW must be pressed twice in order to take out the optical disk, other unspecified people can perform this operation method. Even if an attempt is made to take out the optical disk without knowing, all of them are canceled, so that an accident such as file damage can be prevented. The standby time may be set arbitrarily, but it is necessary to secure at least a time for the operator to press the switch SW twice. On the other hand, if the waiting time is too long, not only the whole process is delayed, but also those who do not know the operation method may push the switch SW twice. Considering these, the waiting time is 1
Seconds are preferred.

FIG. 8 is a flow chart showing an optical disk takeout control method according to the fifth embodiment of the present invention. This embodiment is a control method that combines the above-described second embodiment and third embodiment. That is, when the operator turns on the switch SW to request the ejection of the optical disk, the ejection request detection means 5 detects this and outputs an ejection request signal to the central processing unit 4. Here, the switch SW is continuously turned on while the operator is pressing the switch button.
In this state, the take-out request detecting means 5 continues to output the take-out request signal to the central processing unit 4 during this ON state.

When the extraction request signal is input, the central processing unit 4 sets the extraction request flag as shown in FIG. 2 and executes the extraction control flow shown in FIG. In the control flow, first, it is confirmed whether or not the timing means 7 is operating (step 1), and if it is not operating, the central processing unit 4 is activated.
Issues a start command to the time counting means 7 to count the elapsed time from the time when the takeout request flag is detected (step 2).
The time information obtained by the time measuring means 7 is output to the central processing unit 4. Then, the central processing unit 4 stands by without performing the operation of taking out the optical disc while the preset fixed time has elapsed.

During the waiting time, the central processing unit 4 monitors commands from the host system (step 3). Meanwhile, if a command is received from the host system,
Further, it is determined whether or not the command is a write command (step 9), and if it is a write command,
Without performing the operation of taking out the optical disk, the counting of the elapsed time by the time counting means 7 is stopped (step 7), the taking out request flag is cleared (step 8), and the taking out operation control is ended. The central processing unit, which has completed the take-out operation in this way, proceeds to execute the write command received from the host system, issues a write command to the R / W control unit 3, and writes the information from the host system to the optical disc.

On the other hand, when the received command is not a write command, the received command is processed while the fetch request flag of FIG. 2 is set, and the fetch request flag is detected again, as shown in FIG. The take-out operation control flow is started. At this time, the elapsed time is already counted by the time counting means 7 (step 1), and the process waits as it is for a command from the host system.

Further, the central processing unit 4 detects the takeout request signal during the waiting time (step 4). Then, when the ejection request signal from the ejection request detecting means 5 is interrupted at the time of counting the time by the timing means 7 or in the middle of the waiting time, the elapsed time by the timing means 7 is not executed without executing the ejecting operation of the optical disk. Is stopped (step 7), the take-out request flag is cleared (step 8), and the take-out operation control is ended.

During the waiting time, the extraction request detecting means 5
If the take-out request signal is continuously output from (steps 4 and 5), the central processing unit 4 issues a take-out command to the optical disc take-out means 6 to execute the optical disc take-out operation (step 6). Then, after the take-out operation is completed or in parallel with the take-out operation, the counting of the elapsed time by the time measuring means 7 is stopped (step 7),
The take-out request flag is cleared (step 8), and the take-out operation control ends.

If only the specific person who operates the optical disk drive device is informed that such an operation method, that is, that the switch SW must be kept pressed for a certain period of time to take out the optical disk, another unspecified person Even if you try to eject the optical disk without knowing this operation method, all will be canceled and you can prevent accidents such as file corruption, and also accidents such as file corruption due to ejecting the optical disk before processing the write command. Can be prevented.

FIG. 9 is a flow chart showing an optical disk takeout control method according to the sixth embodiment of the present invention. This embodiment is a control method that combines the above-described second and fourth embodiments. That is, when the operator turns on the switch SW to request the ejection of the optical disk, the ejection request detection means 5 detects this and outputs an ejection request signal to the central processing unit 4. When the extraction request signal is input, the central processing unit 4 sets the extraction request flag as shown in FIG. 7 and sets the extraction request count to 1
And the fetch control flow shown in FIG. 9 is executed.

In the control flow, first, it is confirmed whether or not the timekeeping means 7 is operating (step a), and if not operating, the central processing unit 4 issues a start command to the timekeeping means 7 and the removal request flag is set. The elapsed time from the time of detection is counted (step b). The time information obtained by the time measuring means 7 is output to the central processing unit 4. Then, the central processing unit 4 stands by without performing the operation of taking out the optical disc while the preset fixed time has elapsed.

When the operator turns on the switch SW again during the waiting time, the take-out request detecting means 5 detects this and outputs a take-out request signal to the central processing unit 4.
At this time, since the fetch request flag has already been set, the central processing unit 4 adds 1 to the fetch request count as shown in FIG. That is, the number of retrieval requests is recorded as 2 here.

During the waiting time, the central processing unit 4 monitors the command from the host system (step c). Meanwhile, if a command is received from the host system,
Further, it is determined whether or not the command is a write command (step i), and if it is a write command,
Without performing the operation of taking out the optical disk, the counting of the elapsed time by the time measuring means 7 is stopped (step g), the taking out request flag is cleared (step h), and the taking out operation control is ended. The central processing unit, which has completed the take-out operation in this way, proceeds to execute the write command received from the host system, issues a write command to the R / W control unit 3, and writes the information from the host system to the optical disc.

On the other hand, when the received command is not a write command, the received command is processed while the fetch request flag of FIG. 2 is set, the fetch request flag is detected again, and the process shown in FIG. The take-out operation control flow is started. At this time, the elapsed time is already counted by the time counting means 7 (step a), and the process waits as it is for the command from the host system.

When the waiting time has elapsed (step d), the central processing unit 4 confirms the number of fetch requests (step e), and when two fetch requests are made,
The central processing unit 4 issues a take-out command to the optical disc taking-out means 6 to execute the taking-out operation of the optical disc (step f). Then, after the take-out operation is completed or in parallel with the take-out operation, the counting of the elapsed time by the timer 7 is stopped (step g), the take-out request flag is cleared (step h), and the take-out operation control is ended.

On the other hand, if the removal request has not been made twice, the counting of the elapsed time by the timing means 7 is stopped without executing the removal operation of the optical disk (step g), and the removal request flag is set. After clearing (step h), the take-out operation control ends. If you tell only a specific person who operates the optical disk drive device that such an operation method, that is, that the switch SW must be pressed twice within a certain period of time to take out the optical disk, other unspecified people Even if you try to eject the optical disk without knowing this operation method, all will be canceled and you can prevent accidents such as file damage, and also accidents such as file damage by ejecting the optical disk before processing the write command. Can be prevented.

The present invention is not limited to the above-described embodiment, but can be applied to, for example, a magnetic disk ejection control method. Further, in the fourth embodiment shown in FIG. 6, the optical disk ejecting operation may be executed when the ejecting request is confirmed a predetermined number of times of three times or more, or a predetermined number of times or more (for example, two times or more). The optical disk ejecting operation may be executed when the ejecting request is confirmed. Further, as shown in FIG. 10, the waiting time in each embodiment may be used as a variable value so that the host system can freely change the setting by a specific command. In this way, the standby time can be set according to the write timing of the cache controller and the individuality of the operator.

[0054]

As described above, according to the disc ejection control method of the present invention, even if an operator makes an error operation regarding a disc ejection request, an optical disc ejection operation which is inconvenient in relation to the host system can be performed. It can be automatically prohibited to effectively prevent the trouble of the host system and the damage of the record file.

[Brief description of drawings]

FIG. 1 is a block diagram showing an optical disk drive device for implementing a disk control method according to an embodiment of the present invention.

FIG. 2 is a flowchart showing a flag setting operation for starting the first, second, third and fifth embodiments of the present invention.

FIG. 3 is a flowchart showing an optical disk ejection control method according to the first embodiment of the present invention.

FIG. 4 is a flowchart showing an optical disk ejection control method according to a second embodiment of the present invention.

FIG. 5 is a flowchart showing an optical disk takeout control method according to a third embodiment of the present invention.

FIG. 6 is a flowchart showing an optical disk ejection control method according to a fourth embodiment of the present invention.

FIG. 7 is a flowchart showing a flag setting operation for starting the fourth and sixth embodiments of the present invention.

FIG. 8 is a flowchart showing an optical disk ejection control method according to a fifth embodiment of the present invention.

FIG. 9 is a flowchart showing an optical disc takeout control method according to a sixth embodiment of the present invention.

FIG. 10 is a flowchart showing a modified example of the present invention.

[Explanation of symbols]

 1: I / F control part 2: Data processing part 3: R / W control part 4: Central processing part 5: Ejection request detecting means 6: Optical disk taking out means 7: Timing means

Claims (6)

[Claims] 1. A control method for ejecting a disc loaded in a disc drive device from the device, wherein a certain waiting time is set after a disc take-out request signal is input, and the host system sets within the waiting time. When no command is input, the disc eject operation is executed, while when a command is input from the host system during the waiting time, the disc eject operation is stopped at least during the execution of the command. And a disc ejection control method. 2. A control method for ejecting a disc loaded in a disc drive device from the device, wherein a disc eject operation is executed when a disc eject request signal is continuously input for a certain period of time. Disc ejection control method. 3. A control method for ejecting a disc loaded in a disc drive device from the device, wherein a certain waiting time is set after a disc ejection request signal is input, and a predetermined number of times is set within the waiting time. Or when the disc ejection request signal is input more than a predetermined number of times,
A disc ejection control method characterized by executing a disc ejection operation. 4. A control method for ejecting a disc loaded in a disc drive device from the device, wherein a certain waiting time is set after a disc take-out request signal is input, and the host system sets within the waiting time. A disc ejection control method, wherein a disc ejection operation is executed when no command is input and the disc ejection request signal is continuously input for a certain period of time. 5. A control method for ejecting a disc loaded in a disc drive device from the device, wherein a certain waiting time is set after a disc take-out request signal is input, and the host system sets within the waiting time. A disk ejecting operation is executed when a disk ejecting request signal is input a predetermined number of times or more than a predetermined number of times within a certain waiting time that is the same as or different from the waiting time without inputting a command. Disc ejection control method. 6. The disc ejection control method according to claim 1, wherein the command from the host system is a write command.