JPH10302395A - Recording and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform always recording and reproducing control having high accuracy and to secure environment for operating appropriately the recording and reproducing device in a recording and reproducing system independently of error of a data rate of data externally delivered and received. SOLUTION: This device is constituted so that an interrupt event request is generated in accordance with rising/falling timing of an external synchronizing signal and a CPU performs recording and reproducing control by this interrupt event request. Also, this device can cope with a situation in which a high speed data rate is set exceeding tolerance by performing appropriate processing in accordance with a level of stability of interrupt event processing for a synchronizing signal frequency.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a recording / reproducing apparatus for recording or reproducing data corresponding to, for example, a tape-shaped recording medium.

[0002]

2. Description of the Related Art For example, in a magnetic recording / reproducing apparatus for performing magnetic recording / reproducing of data corresponding to a tape-shaped recording medium, a transfer rate of input / output data (hereinafter simply referred to as a data rate) is usually set in advance. A fixed value is specified. When the recording / reproduction control is performed in the magnetic recording / reproduction device, a control table in which necessary control parameters and the like are set in accordance with the data rate is operated based on a clock having a unique internal cycle. And various recording / reproduction controls are executed in accordance with the control table.

[0003]

When a relatively large-scale recording / reproducing system including the above-described magnetic recording / reproducing device is constructed, for example, the data rate of a system device other than the magnetic recording / reproducing device may be higher than that of a magnetic recording / reproducing device. In some cases, the environment may differ from the data rate required by the recording / reproducing apparatus with a certain error. When the recording / reproducing system is operated in such a situation, jitter occurs between a data rate of data to be transmitted / received to / from an external device and a control table which is uniquely set in the magnetic recording / reproducing device. As a result, there arises a problem that a highly accurate recording / reproducing operation cannot be expected.

For this reason, even if the data rate of the data recorded and reproduced by the recording / reproducing device is originally different from the reference value required by the recording / reproducing device, the recording / reproducing device does not need to use the data rate. It is preferable that a required recording / reproducing process is executed in synchronization with the process. When this object is realized, the recording / reproducing apparatus executes the recording / reproducing process based on the synchronization timing given from the outside. However, the synchronization timing and the control operation timing in the recording / reproducing apparatus are compatible. In such a case, it is preferable that the recording / reproducing apparatus be configured to be capable of self-defense so that the recording / reproducing apparatus as the recording / reproducing system can be appropriately operated.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a recording / reproducing apparatus for recording or reproducing data corresponding to a predetermined type of recording medium.
Interrupt event processing execution means for executing required interrupt event processing related to recording or reproduction operation at a timing synchronized with a synchronization signal supplied from the outside in synchronization with recording / reproduction data corresponding to the recording / reproduction device; A frequency measuring means capable of measuring the frequency of the synchronizing signal, and using the frequency measured by the frequency measuring means, an interrupt event is performed once for a synchronizing signal section corresponding to the start timing of the interrupt event processing. Occupancy rate identification means for identifying how much occupancy rate the time required for the process has, and an operation state of the interrupt event processing when the occupancy rate identified by the occupancy rate identification means is equal to or greater than a first threshold. Is determined to be in a first state, and is determined to be within a range between a first threshold and a second threshold smaller than the first threshold. Operating state judging means for judging the second state when it is determined to be less than or equal to the second threshold value, and judging the state to be the third state when it is judged that the state is equal to or less than the second threshold value. And a corresponding processing control means for executing a required corresponding processing in accordance with the above.

In the recording / reproducing apparatus having the above-described configuration, a necessary interrupt event process related to the recording / reproducing operation can be executed in synchronization with an external synchronization signal synchronized with the recording / reproducing data, and then the current synchronization signal is processed. Of the interrupt event processing time in the recording / reproducing apparatus with respect to the start timing (predetermined synchronization signal section) of the interrupt event processing determined based on the occupancy, and based on the occupancy, the stability of the recording / reproducing control operation is determined. The level at which the interrupt event processing is impossible (the first state), the level at which the processing is possible but almost impossible (the second state), and the level at which the processing is more stable than the second state are enabled. Level (third state), and it is possible to execute an appropriate process based on the determination result.

[0007]

Embodiments of the present invention will be described below. The recording / reproducing apparatus according to the present embodiment is a magnetic recording / reproducing apparatus capable of recording / reproducing data corresponding to a tape-shaped recording medium.

In the present embodiment, as will be described later, the execution timing of the required event processing in the recording / reproducing apparatus is determined based on a synchronization signal supplied from outside in synchronization with data (hereinafter referred to as an external synchronization signal). The concept of the external synchronization signal in the present embodiment will first be described with reference to FIG. For example, in the recording and reproduction of digital data, a reference clock exists as shown in FIG. 1B, and the data shown in FIG. 1A exists in synchronization with this clock. Has been. The data rate corresponds to the clock timing shown in FIG. In addition, the data referred to here is recording / reproducing data exchanged between recording / reproducing systems constructed by including the magnetic recording / reproducing apparatus of the present embodiment.
As shown in (a), the data is grouped into blocks of a predetermined unit. Then, as shown in FIG. 1C, an external synchronization signal exists in synchronization with the data. In this case, the external synchronization signal is made to exist as a clock having a timing corresponding to a data block unit.

The magnetic recording / reproducing apparatus of this embodiment generates an interrupt event request (timing signal) required for internal recording / reproducing control based on the external synchronization signal, as described later. Accordingly, for example, in a state where the data rate of the data shown in FIG. 1A has an error within a predetermined allowable range with respect to the reference data rate originally required by the magnetic recording / reproducing apparatus. If so, the recording and reproducing operation in synchronization with the actual data rate can be performed.

FIG. 2 is a block diagram schematically showing a configuration of a main part of a magnetic recording / reproducing apparatus according to an embodiment of the present invention for each functional block. As shown in FIG. 1, the magnetic recording / reproducing apparatus 1 includes an external control communication block 2, a system control block 3, a servo / mechanism control block 4, and a digital signal control block 5. The external control communication block 2 is a functional circuit unit for executing communication between the magnetic recording / reproducing apparatus 1 and a host system 0 formed by an external device in order to realize a linked operation as a recording / reproducing system. , And an external interface IF for communicating with the outside. The data (D), clock (CLK), and external synchronization signal (Sync) described with reference to FIG.
Transmission is performed between the magnetic recording / reproducing apparatus 1 and the host system 0 via F. In the present embodiment, a display unit 6 and a speaker 7 are provided for the external control communication block 2. The display section 6 displays required contents according to the operation state of the magnetic recording / reproducing apparatus. From the speaker 8, for example, an audio signal generated by the external control communication block 2 is output as audio. Although not shown, the external control communication block 2 is provided with an operation unit for the user to perform various operations, and executes processing based on the operation performed on the operation unit. A command signal corresponding to an operation performed on the operation unit is transmitted to a required control block.

The system control block 3 communicates with the external control communication block 2, the servo / mechanism control block 4, and the digital signal control block 5, for example, to concentrate control operations on the magnetic recording / reproducing apparatus 1. Management. In the present embodiment, the external synchronization signal Sync transmitted from the external control communication block 2 is used.
, An interrupt event request (timing signal) for executing a required internal recording / reproducing operation can be generated. This will be described later.

The servo / mechanism control block 4 includes, for example, a drive mechanism for driving and driving a magnetic tape during recording and reproduction, a head mechanism for performing magnetic recording and reproduction on the magnetic tape, and various servo circuit systems. This is a functional block for appropriately performing necessary control on.

For example, at the time of recording, the digital signal control block 5 performs an encoding process in a predetermined format and an ECC (ECC
(rrorCorrecting Code) Performs necessary signal processing including encoding processing and the like to generate recording data, and executes signal processing such as decoding processing corresponding to the format at the time of recording and ECC decoding processing at the time of reproduction. Obtain playback data. The reproduced data is transmitted to the external control communication block 2 under the control of the system control block 3, for example.
From the host system 0 via the external interface IF
Is transmitted to

FIG. 3 shows, as an internal configuration of the system control block 3, a portion related to the timing generation of the interrupt event processing as a functional block. In the figure, an external synchronization signal Sync is supplied to a frequency measurement circuit 11. The frequency measurement circuit 11 measures the frequency of the input external synchronization signal Sync, and transmits the measurement result to a CPU (Central Processing Unit) 14.

In this case, the external synchronization signal Sync is a rectangular wave signal corresponding to the cycle. Therefore, the rising / falling detection circuit 12 outputs the external synchronization signal Sync.
Edge, that is, rising and falling,
This detection signal Sd is output to the interrupt controller 13. The interrupt controller 13 responds to the timing of the detection signal Sd output from the rising / falling detection circuit 12 and outputs the interrupt request event Sirp to the CP.
Transmit to U14. The CPU 14 executes necessary interrupt processing for recording and reproduction control at the timing when the interrupt request event Sirp is obtained. The CPU 14, the frequency measurement circuit 11, the rise / fall detection circuit 12, and the interrupt controller 13 can communicate with each other via a bus line BL.

FIG. 4 is a timing chart showing an operation of generating an interrupt event request realized by the system control block 3 having the above configuration. In FIG. 4A,
External synchronization signal Sy input to system control block 3
nc is shown. In this case, the rise / fall detection circuit 12 outputs the external synchronization signal Sy shown in FIG.
In response to the edge of nc, for example, a detection signal Sd shown in FIG. Here, the detection signal Sd outputs a single H-level pulse according to the rising timing and the falling timing of the multiplied signal Sf. Then, in response to the pulse output of the detection signal Sd, the interrupt controller 13 responds to FIG.
The interrupt event request S at the timing indicated by the arrow
irp will be generated.

As a result, the interrupt event request Sirp is synchronized with the inversion timing of the external synchronization signal Sync shown in FIG. That is, it is generated at twice the frequency of the external synchronization signal Sync.
Then, the CPU 14 sets the interrupt event request Sirp
The required recording / reproduction control (interrupt event processing) for the external communication control block 2, the servo / mechanism control block 4, and the digital signal control block 5 is executed based on As a result, in the magnetic recording / reproducing device 1 of the present embodiment, the external synchronization signal Sync
The required recording / reproduction control is executed in synchronization with the double frequency. Therefore, the control timing is synchronized with the data rate of the data D input from the outside, for example.

It should be noted that the CPU 14 also executes processing based on clock timing generated inside the magnetic recording / reproducing apparatus. Therefore, the “interrupt event processing” here means a processing operation to be performed corresponding to the timing of the data D in units of blocks (see FIG. 1). On the other hand, the processing based on the clock timing generated inside the magnetic recording / reproducing apparatus is referred to as “independent event processing” in this specification.

As described above, according to the present embodiment, for example, even when the data rate of the external device is different from the reference data rate originally required by the magnetic recording / reproducing apparatus 1 within a predetermined allowable range, Control is performed so that various processes can be executed at a timing synchronized with the data rate. For example, a recording / reproducing operation with higher accuracy is realized than when a control table is constructed based on an internal unique clock. Will be.

FIG. 5 shows three examples of the timing of the interrupt event processing for the external synchronization signal Sync of different frequencies. FIG. 5A shows the first example.
(B). FIG. 5A shows an external synchronization signal Sync at a certain frequency. FIG. 5B shows an interrupt event processing timing executed by the CPU 14 in response to the above-described interrupt event request. In FIG. 5, T is Ｔ of the external synchronization signal Sync.
Indicates the time of the cycle (reversal section). Tev indicates the interrupt event processing time, that is, the time from the start to the end of one interrupt event process. Also, CP
The interrupt event processing time executed by U14 is
Actually, it differs every time depending on the conditions such as the type of processing and the like. However, here, for example, the longest required time empirically obtained is uniformly set to the interrupt event processing time Tev.
It shall be shown as.

Here, the interrupt event request Sirp
When the CPU 15 properly executes processing according to (see FIG. 4), the half cycle T of the external synchronization signal Sync needs to exceed the interrupt event processing time Tev. In the first example, a state is shown in which the 周期 cycle T and the interrupt event processing time Tev are appropriate. That is, the event processing time Tev shown in FIG.
The half cycle T shown in (a) is in a sufficiently long state. 1
Since the / 2 cycle T is determined by the frequency of the external synchronization signal Sync, when the states shown in FIGS. 5A and 5B are obtained, the data rate and the data rate of the recording / reproducing system of the present embodiment are determined. It can be seen that the state is consistent with the control operation timing inside the recording / reproducing apparatus. In this specification, such a state is referred to as a “steady state”.

FIGS. 5C and 5D show a second example. FIG. 5 (c) shows an external synchronization signal Sync having a higher frequency than that of FIG. 5 (a).
The / 2 cycle T is shorter than the case of FIG. 5A according to the change in the frequency of the external synchronization signal Sync. FIG. 5D shows the interrupt event processing timing corresponding to the external synchronization signal Sync of FIG. 5C. The event processing time Tev shown in FIG.
Same as (b). This means that the interrupt event processing time executed inside the magnetic recording / reproducing apparatus 1 is the same regardless of a change in the frequency of the external synchronization signal Sync.

In the second example, the occupation ratio of the event processing time Tev with respect to the half cycle T is larger than that in the first example because the frequency of the external synchronization signal Sync is increased. Have been. That is, a state is shown in which there is no room in the period from the end point of the current event processing to the inversion position of the external synchronization signal Sync corresponding to the start point of the next event processing. In this state, the CPU 14 can still properly execute the interrupt event processing, but for some reason, the frequency of the external synchronization signal Sync is further increased (the data rate is set to a high speed). In this case, there is a high possibility that the end point of the current event processing exceeds the inversion point of the external synchronization signal Sync which should be the start point of the next event processing. In other words, if the data rate further changes from this state to a higher data rate, it can be regarded as a state of low operation stability in which proper recording and reproduction operations cannot be guaranteed. In this specification, this state is referred to as a “warning (warning) state”.

FIGS. 5E and 5F show a third example. FIG. 5 (e) shows the external synchronization signal Sync having a higher frequency than that of FIG. 5 (c). Therefore, the 周期 cycle T of this figure is further more than that of FIG. 5 (c). In a short state. Again, FIG. 5 (f) shows FIG. 5 (b)
The same interrupt event processing timing as in (d) is shown.

In the third example, a state is shown in which the period of the interrupt event processing time Tev exceeds the period of the half cycle T because the half cycle T is further shortened. That is, the data rate of the data D is set to be high enough to exceed the fluctuation range that the magnetic recording / reproducing apparatus 1 can handle. In this state, for example, the start point of the next interrupt event process (FIG. 5 (e))
As a result, the execution timing of the interrupt event process is not synchronized with the external synchronization signal Sync as a result of being shifted from the inversion position of the external synchronization signal Sync (FIG. 5F). Therefore, the magnetic recording / reproducing apparatus 1 cannot perform a proper recording / reproducing operation. In this specification, this state is referred to as an “error state”.

In the present embodiment, as the timing of the interrupt event processing, the CPU 14 identifies which of the steady state, the warning state, and the error state, as will be described later, and identifies the state. By executing a process according to the state, the self-defense is performed so that an abnormal recording / reproducing operation does not occur.
Specifically, in the steady state, there is no particular problem, so that the interrupt event processing is executed. That is, the recording / reproducing operation is continued as it is. Further, under the warning state, since the appropriate recording / reproducing operation is at a level that can be maintained, the interrupt event processing is executed. However, a warning is issued to the outside that the current state is the warning state by a predetermined presentation form. Output a message. Further, under the error state, since an appropriate recording / reproducing operation cannot be expected, the interruption event process is not executed. For example, if the recording / reproducing operation has been performed, this operation is stopped. At the same time, a process for outputting a message indicating an error state to the outside is executed. FIGS. 5 (g) and 5 (h) show the results of the execution of the error handling processing. That is, FIG.
The error handling process as an independent event process is performed on the external synchronization signal Sync shown in FIG. 5 at the timing of the event processing time Tev shown in FIG.

When the user receives the warning or error message, for example, the data rate (that is, the external synchronization signal frequency) is adjusted so that the interrupt event processing timing between the host system and the magnetic recording / reproducing apparatus 1 can be matched. ) Can be changed. As the warning or error message, for example,
In the display unit 6, a display indicating a warning state or an error state is performed in a predetermined display mode, or a warning sound indicating a warning state or an error state is output from the speaker 7. What should be done is. Furthermore, it is also conceivable to configure so that a warning or an error message is output to an external device forming the host system 0.

FIG. 6 is a flowchart showing an example of a processing operation for realizing the interrupt event processing according to the present embodiment described above. This process is executed by the CPU 14 shown in FIG. In the routine shown in this figure, first, based on the frequency of the external synchronization signal Sync read from the frequency measurement circuit 11 in step S101, a half cycle T of the external synchronization signal Sync is used.
(In this case, time information) is calculated. Then, in the subsequent step S102, it is determined whether or not T × a ≧ Tev (a is a coefficient, 1 <a) holds. Here, 1/2
The coefficient a of the cycle T is set to the minimum value that corresponds to the error state as the occupancy of the interrupt event processing time Tev with respect to the half cycle T, and specifically, a value of about 0.9 is set. Here, if the coefficient a ≒ 0.9, the interrupt event processing time Tev is actually が cycle T
Is included in the range in which the appropriate interrupt event processing can be executed, but in the present embodiment, the coefficient a is set to a value less than 1 as described above. The required margin is obtained to ensure the stability of the recording / reproducing operation.

If an affirmative result is obtained in step S102 and it is determined that the occupancy of the interrupt event processing time Tev with respect to the half cycle T is at the level of the error state, the process proceeds to step S103, where the error state is determined. Is set, and the processing of this routine is terminated. On the other hand, if a negative result is obtained in step S102, the process proceeds to step S104.

In step S104, it is determined whether or not T × b ≧ Tev (b is a coefficient, b <a). The coefficient b is
Interrupt event processing time Tev for 1/2 cycle T
Is set as the minimum value corresponding to the warning state. Specifically, also in this case, b ≒ 0.5 is set in consideration of a certain margin. This step S
If a positive result is obtained in 104 and it is determined that the vehicle is in the warning state, the process proceeds to step S105, where a warning flag F2 indicating the warning state is set, and the process proceeds to step S107. On the other hand, if a negative result is obtained in step S104 and it is determined that the vehicle is in the steady state, the process proceeds to step S106.

In step S106, for example, if there is an error flag or warning flag that has been set, the flag or warning flag is reset and cleared.
Proceed to. In step S107, an interrupt event process is executed at a timing corresponding to the interrupt event request Sirp (see FIG. 4). By executing the processing in step S107, the recording / reproducing operation is started or continued in the steady state and the warning state. On the other hand, when it is determined that the error state is present, the process ends without executing the process of step S107, and thus the recording / reproducing operation is not started or stopped.

FIG. 7 shows an independent event processing operation executed by the CPU 14 in response to the above-described interrupt event processing. In step S201, the CPU 15 determines whether or not the error flag F1 is set. If the CPU 15 determines that the error flag F1 is set, the process proceeds to step S202, and a message indicating that it is in an error state is displayed. Executes a required processing operation for outputting to the outside. If it is determined in step S201 that the error flag F1 has not been set,
Subsequently, in step S203, the warning flag F2
Is determined as to whether or not is set. If a positive result is obtained, the process proceeds to step S204 to execute a required processing operation for outputting a message indicating that the current state is a warning state to the outside. However, if a negative result is obtained and it is determined that the mode is the normal mode, the processing operation ends.

It should be noted that the present invention is not limited to the configuration of the above embodiment, and various changes can be made in accordance with actual use conditions and the like. For example, in the above-described embodiment, a case where a synchronization control device is mounted on a magnetic recording / reproducing device has been described. However, the present invention is not limited to this, and a recording / reproducing operation is performed in synchronization with an external synchronization signal. It is also conceivable to apply to other types of recording devices or playback devices that need to be.

[0034]

As described above, according to the present invention, even if the data rate of the recording / reproducing data has an error within a predetermined allowable range with respect to the data rate required by the recording / reproducing apparatus, the data rate of this data rate can be reduced. The recording / reproducing process (interrupt event process) is executed in synchronization with. In addition, based on the relationship between the period of the external synchronization signal and the occupation rate of the interrupt event processing time, an error state in which interrupt event processing is not possible, a warning state in which the level is possible but nearly impossible, and a stable state are possible. The recording / reproducing system in the recording / reproducing system by appropriately determining whether the recording / reproducing apparatus is in a normal state or not, and performing appropriate processing based on the determination result. It is possible to do.

[Brief description of the drawings]

FIG. 1 shows an external synchronization signal according to an embodiment of the present invention;
FIG. 4 is a waveform diagram showing data and clock timings synchronized with the external synchronization signal.

FIG. 2 is a block diagram illustrating a configuration example of a magnetic recording / reproducing apparatus according to the embodiment.

FIG. 3 is a block diagram illustrating an example of an internal configuration of a system control block.

FIG. 4 is a timing chart showing the generation timing of an interrupt event request according to the present embodiment.

FIG. 5 shows a relationship between a frequency of an external synchronization signal and an interrupt event processing time, a steady state, a warning state,
It is explanatory drawing which illustrates the state made into an error state and an error processing state.

FIG. 6 is a flowchart illustrating a processing operation of a CPU at the time of interrupt event processing according to the present embodiment;

FIG. 7 shows a CP executed in correspondence with the processing operation shown in FIG. 6;
It is a flowchart which shows the processing operation of U independent event processing.

[Explanation of symbols]

0 upper system, 1 magnetic recording / reproducing device, 2 external communication control block, 3 system control block, 4 servo / mechanism control block, 5 digital signal control block, 6 display, 7 speaker, 11 frequency measurement circuit, 12 rise / stand Fall detection circuit, 13 interrupt controller, 14 CPU, IF external interface, BL bus line, Sync external synchronization signal, CLK clock, D data, Sirp interrupt event request

Claims (4)

[Claims] 1. A recording / reproducing apparatus for recording or reproducing data corresponding to a predetermined type of recording medium, wherein the recording / reproducing apparatus synchronizes with a synchronization signal supplied from outside in synchronization with the recording / reproducing data corresponding to the recording / reproducing apparatus. Interrupt event processing executing means capable of executing required interrupt event processing relating to recording or reproducing operation at the specified timing; frequency measuring means capable of measuring the frequency of the synchronization signal; and measurement by the frequency measuring means. Occupancy rate identification means for identifying how much occupancy time required for one interrupt event processing for a synchronization signal section corresponding to the start timing of the interrupt event processing using the set frequency. The occupancy rate identified by the occupancy rate identification means is the first operating state of the interrupt event processing. If it is equal to or greater than the threshold, it is determined to be in the first state, and if it is determined that it is within the range between the first threshold and a second threshold smaller than the first threshold, it is determined to be in the second state. The operation state determining means for determining that the state is the third state when the state is determined to be equal to or less than the second threshold value; and performing a necessary corresponding process in accordance with the operation state determined by the operation state determining means. And a corresponding processing control means for executing. 2. The recording apparatus according to claim 1, wherein the response processing control means does not execute the interrupt event processing when the operation state determination means determines that the operation state is the first state. Playback device. 3. The response processing control means executes the interrupt event processing when the operation state determination means determines that the operation state is the second state, and may not properly execute the event processing. 2. The recording / reproducing apparatus according to claim 1, wherein information indicating the possibility is presented in a predetermined presentation form. 4. The recording apparatus according to claim 1, wherein the response processing control means executes the interrupt event processing when the operation state determination means determines that the state is the third state. Playback device.