JPH03212864A - Magnetic reproducing device - Google Patents

Abstract

PURPOSE:To enable reverse reproducing with simple constitution by processing bit inversion of a reproducing frame address data at the time of the reverse reproducing or normal reproducing. CONSTITUTION:The device is provided with a demodulation means 40 for demodulating a regenerative signal SRF and extracting the reproducing frame address data FAD, an inversion means 42 for inverting the reproducing frame address data FAD in bit and outputting it at the time of the normal reproducing or reverse reproducing and a reference frame address data generating means 46 for generating a reference frame data FREF which will increase or decrease circulatively in a prescribed period, and so forth. Then, a capstan motor 32 is driven in order to make the data FAD coincide with the data FREF based on a comparison result between the reproducing frame address data FFD which has been reproduced or bit-inverted and the reference address data FREF. By this method, the reverse reproducing can be performed with simple constitution.

Description

[Detailed description of the invention] The present invention will be explained in the following order.

A. Industrial field of application B. Overview of the invention C. Conventional technology Problems to be solved by the invention E. Means for solving the problem (Fig. 1 and 2) F. Effect (Fig. 1 and 2) Figure) G Embodiment (Figures 1 and 2) (G1) Structure of the embodiment (G2) Operation of the embodiment (G3) Effects of the embodiment (G4) Other embodiments H Effects of the invention A Industrial Field of Application The present invention relates to a magnetic reproducing device, and can be applied to, for example, a digital audio recorder for recording and reproducing digital audio signals.

B. Summary of the Invention The present invention enables reverse playback with a simple configuration by inverting and processing the bits of playback frame address data during reverse playback or normal playback in a magnetic playback device.

C. Prior Art Conventionally, some magnetic recording and reproducing apparatuses (hereinafter referred to as digital audio recorders) are capable of recording and reproducing digital audio signals using a rotating drum.

In this digital audio chip recorder,
The recording time can be changed by changing the transmission speed of the recording signal, and by changing the running speed of the magnetic tape and the rotational speed of the rotary drum to record the digital audio signal.

In other words, in the standard mode, the digital audio signal is divided into blocks with a period of 30 (msec) and interleaved, whereas in the long time mode,
Interleave processing is performed by forming blocks at a cycle of 60 (msec).

Furthermore, the interleaved audio data is converted into a recording signal together with error detection and correction codes, and at this time, the transmission rate of the recording signal is set to 172 in the standard time mode in the long time mode.

Furthermore, in the long-time mode, the rotational speed of the rotating drum and the running speed of the magnetic tape are set to 172 in the standard mode, thereby increasing the recording track formation speed to 1 in the standard mode.
Set to 72.

As a result, in the standard mode and long-time mode, the digital audio signal locked at 30 (ssec) and 60 (msec 1 cycle) is sequentially
It is possible to allocate and record to one recording track and switch the recording time.

D Problems to be Solved by the Invention By the way, when recording by switching the transmission speed of the recording signal, if the reproduction is performed under the same conditions as during recording, the reproduction signal with different transmission speeds will be generated in the standard mode and long-time mode. can get.

In this case, in the reproduced signal processing circuit, it is necessary to switch the characteristics of the equalizer circuit and the like between the standard mode and the long-time mode, which inevitably makes the overall configuration more complicated.

For this reason, in this type of digital audio tape recorder, a method has been proposed to obtain a playback signal with the same transmission speed in the long-time mode and standard mode by switching the rotation speed of the rotating drum during playback (Japanese Patent Application Laid-Open No. Publication No. 187973/1982, Japanese Patent Application Publication No. 19337/1983
No. 5, JP-A-63-193376, JP-A-6
3-206861).

In other words, in long-time mode, if the rotating drum is driven at twice the rotational speed during recording, it is possible to obtain a playback signal that is maintained at twice the transmission speed of the recorded signal, and playback with the same transmission speed as in the standard mode. I can get a signal.

At this time, since each magnetic head scans each recording track twice, it is possible to reproduce a digital audio signal by demodulating the reproduction signal and selectively outputting the resulting reproduction data. .

Furthermore, at this time, the servo circuit extracts the frame address data assigned to each recording track from the reproduced data, and drives the capstan motor so that the frame address data is sequentially updated by 1 every two rotations of the rotating drum. (hereinafter referred to as NT servo).

As a result, the servo circuit can perform tracking control on the capstan motor, and perform υrm so that each magnetic head reliably scans one recording track twice.

In this way, switching of the equalizer circuit and the like can be omitted in the standard mode and long-time mode, and the overall configuration can be simplified accordingly.

However, this type of digital audio recorder has a reverse playback mode in which the running direction of the magnetic tape is reversed for playback.

In this case, during normal playback, the reproduced frame address data is updated so that the value l is sequentially added to it, whereas in reverse playback mode, it is updated so that the value is sequentially reduced by 1. Ru.

Therefore, in the NT servo water circuit, an up-counter circuit and a down-counter circuit that operate in synchronization with the rotation of the rotating drum are required, which causes the problem that the overall configuration becomes complicated.

The present invention has been made in consideration of the above points, and it is an object of the present invention to propose a magnetic reproducing device that can perform reverse reproduction with a simple configuration.

El.1 Means for Solving Problems In order to solve this problem, the present invention provides a magnetic system in which frame address data whose value increases or decreases sequentially and cyclically is recorded on recording tracks in sequence together with predetermined data DAu. In the magnetic reproducing device 1 that reproduces the tape 20,
A demodulating means 40 demodulates the reproduced signal 5IIF and extracts the reproduced frame address data FAD, and a bit inverting means 42 bit-inverts and outputs the reproduced frame address data FAD during normal reproduction or reverse reproduction, which are sequentially circulated at a predetermined period. a reference frame address data generation means 46 that generates reference frame address data FIEF whose value increases or decreases, reproduced frame address data F'Ao or bit-inverted reproduced frame address data Fao, and reference frame address data F0F; Based on the comparison result of the playback frame address data FA
D or bit-inverted playback frame address data F
Capstan motor driving means 48 and 50 are provided to drive the capstan motor 32 so that AD matches the reference frame address data F'*tA.

Based on the comparison result between the F action playback frame address data FAD or the bit-inverted playback frame address data FAo and the reference frame address data Fl11F, the playback frame address data FAD or the bit-inversion playback frame address data FAIJ becomes the reference frame address. By driving the capstan motor 32 so as to match the data FIEF, reverse reproduction can be performed with a simple configuration that simply inverts the bits of the reproduction frame address data FAI.

G example An embodiment of the present invention will be described in detail below with reference to the drawings.

(G1) Configuration of the Embodiment In FIG. 1, 1 indicates a digital audio recorder as a whole, and receives stereo audio signals S0 and S. Record and play back UT.

That is, in the digital audio tape recorder 1, the input display circuit 2 having an arithmetic processing circuit configuration outputs operation data D sou in response to the operation of the operator.
The display on the display panel is switched based on predetermined control data.

As a result, the digital audio tape recorder 1
In this system, the operation is switched in response to the operation of the operator, and the operating state can be confirmed through the display on the display panel.

The system control circuit 6 receives the operation data D,. 1, the control data DCON is output to the digital signal processing circuit 8 and the servo circuit 10, thereby switching the operation of the digital audio recorder 1.

That is, the audio signal conversion circuit 12 converts the audio signal S1 into a digital audio signal DAυ based on the clock signal S8 output from the digital signal processing circuit 8, and outputs the digital audio signal DAυ to the digital signal processing circuit 8. At the same time, a digital audio signal is output from the digital signal processing circuit 8. is converted into an audio signal 5out consisting of an analog signal and output.

On the other hand, during recording, the digital signal processing circuit 8 divides the digital audio signal DAL+ into blocks at an interleaving period, performs interleaving processing, stores it in the memory circuit 14 together with predetermined frame address data, etc., and then processes the digital audio signal DAL+ for error detection and correction. The code is generated and the memory circuit 14
Store in.

Further, the digital signal processing circuit 8 sequentially reads out the data stored in the memory circuit 14, modulates the data by 1°-8, adds a pilot signal for tracking control, etc., and converts the data into a recording signal S□0.

At this time, the digital signal processing circuit 8 selects the interleave period to be 30 (*5 ec) and 60 Cm5 ec) in the standard mode and the long time mode, respectively, and sets the transmission speed of the recording signal S□0 to 9.4 sec, respectively.
08 (Mbps) and 4.704 (Mbps)
and select the recording signal S□. Record/playback amplifier circuit 1
6 to the magnetic heads 18A and 18B.

Here, the magnetic heads 18A and 18B are connected to the magnetic tape 20.
Wrapping at 90 degrees means winding at an angle of 30 [Sono Meng]
They are arranged on the rotating drum 22 at angular intervals of 180 degrees.

As a result, in the digital signal processing circuit 8, the digital audio signals that are divided into blocks at the interleaving period are sequentially recorded via the magnetic heads 18A and 18B in the period of one rotation of the rotary drum 22, and the standard mode and long It is possible to record digital audio signals sequentially according to a standardized format for time mode.

On the other hand, during reproduction, the digital signal processing circuit 8 generates reproduction signals S, !, obtained via the recording/reproduction amplification circuit 16.
, to obtain reproduced data, and store the reproduced data in the memory circuit 14.

Further, the digital signal processing circuit 8 performs error detection and correction processing on the reproduced data stored in the memory circuit 14, and then performs an ink-leave processing in the opposite manner to that during recording, and outputs a digital audio signal DAL+.

As a result, the digital audio recorder I
, the digital audio signal DAU recorded on the magnetic tape 20 is reproduced to generate the audio signal S. U
It is designed to be able to output T.

At this time, when reproducing the magnetic tape 20 recorded in the standard mode, the digital signal processing circuit 8 sequentially processes the reproduction signal S0 to obtain reproduction data and outputs the digital audio signal DAU.

On the other hand, magnetic tape 2 recorded in long-time mode
0, the reproduction data sequentially obtained in the NT servo state is selectively stored in the memory circuit 14, and then converted into a digital audio signal DAU and output. In the present invention, it is possible to obtain a reproduction signal S□ with a high transmission speed and reliably stop the digital audio signal DAL+ with a simple configuration.

Further, the digital signal processing circuit 8 outputs a rotating drum reference signal DREF that is repeated at an interleaving period to the servo circuit 10, so that the rotation of the rotating drum 20 is synchronized with the signal processing timing of the digital signal processing circuit 8. ing.

Furthermore, during long-time mode playback, the digital signal processing circuit 8 extracts frame address data (hereinafter referred to as playback frame address data) Fat from the playback data and outputs it to the servo circuit 10, thereby ensuring that the NT servo Tracking control is possible.

Here, the frame address data FAD is 4-bit data representing the position information of the recording track, and during recording, the value is added by 1 every interleave cycle, and the value is sequentially and cyclically added in the range from value O to value F. It is designed so that it can be switched.

The servo circuit 10 receives control data D, which is output from the system control circuit 6. The operation is switched based on N7, and the drum motor 30, cab stan motor 32, and reel motor 34 are driven at a predetermined speed.

That is, during recording, the servo circuit IO controls the drum motor 30 based on the rotating drum reference signal D*Er so that the rotating drum 22 rotates once at the interleave period.

At this time, the servo circuit 10 drives the capstan motor 32 so that the magnetic tape 20 runs at two track pitches at an interleave period.

As a result, the servo circuit 10 drives the rotating drum 22 and the magnetic tape 20 at a predetermined speed, and in the standard mode and long-time mode, each magnetic head 18A and 18B records at a cycle of 30 (msec) and 60 [m5ec], respectively. It is arranged to form a track.

As a result, the digital audio tape recorder 1
In standard mode, 30 [wasec
), the transmission rate is 9.408 (Mb
The digital audio signal converted to the recording signal S0C of
recorded on one recording track.

On the other hand, in the long-time mode, 60[-5e
After being blocked in c), the transmission rate is 4.704 (M
The digital audio signal converted into the recording signal S wzc (bps) is sequentially allocated to two recording tracks and recorded.

On the other hand, during playback, the servo circuit 10
The running speed of 0 is maintained at the same speed as when recording.

Furthermore, when reproducing the magnetic chip 120 recorded in the standard mode, the servo circuit 10 drives the drum motor 30 in the same way as during recording, and also controls the A according to the tracking error signal output from the tracking control circuit 36.
T F (automatic trackfindi)
ng)) Control the capstan motor 32 using a racking control technique.

This allows the digital audio tape recorder to
When reproducing the magnetic tape 20 recorded in the standard mode, the transmission speed 9 is the same as that of the recording signal S REC.
．． Playback signal 5II held at 408 (Mbps)
You can get F.

On the other hand, magnetic tape 2 recorded in long-time mode
When reproducing 0, the servo circuit 10 drives the rotating drum 30 in the same way as when reproducing the magnetic tape 20 recorded in the standard mode, and maintains the running speed of the magnetic tape 20 at the same speed as during recording.

Furthermore, at this time, the servo circuit 10 receives the reproduction frame address data FA output from the digital signal processing circuit 8.
Based on D, the capstan motor 32 is tracked and controlled to ensure NT servo.

That is, as shown in FIG. 2, in the servo circuit 10, the reproduction frame address data F'io output from the demodulation circuit 40 of the digital signal processing circuit 8 is sent to the reproduction frame address detection circuit 44 via the OR circuit 42. and latches the reproduction frame address data F An at an interleave period.

The OR circuit 42 receives control data DI output from the system control circuit 6. , li, the servo circuit 10
A reverse playback switching signal S whose logic level is inverted between normal playback and reverse playback is supplied from a control circuit (not shown).
Enter F/11.

As a result, in the playback frame address detection circuit 44, during normal playback, the playback frame address data F'
While ao is latched as is, during reverse playback, address data obtained by bit-inverting the playback frame address data FAD is latched.

Therefore, since the frame address data consists of recording track position information that is sequentially and cyclically updated in the range from value 0 to value F, during normal playback, the value increases sequentially at the interleave period via the demodulation circuit 40. The reproduction frame address data FAEI is obtained, and the reproduction frame address data F'a.

is latched as is in the playback frame address detection circuit 44.

On the other hand, during reverse playback, the demodulation circuit 40
The reproduced frame address data F'io whose value sequentially decreases in the interleave cycle is obtained through the interleave cycle, and the bits of the reproduced frame address data F'io are inverted in the OR circuit 42 to obtain frame address data whose value sequentially increases. After being converted into , it is latched by the playback frame address detection circuit 44 .

Thus, in the servo circuit 10, even during reverse playback, frame address data whose value increases sequentially can be obtained as recording track position information in the same way as during normal playback.

Therefore, during reverse playback, the latched frame address data can be processed and tracked in the same way as during normal playback.

Therefore, reverse reproduction can be performed with a simple configuration that simply inverts the bits of the reproduction frame address data FAII.

That is, the reproduction frame address detection circuit 44 outputs the latched frame address data to the reference frame address counter circuit 46 and the comparison circuit 48.

The reference frame address counter circuit 46 has an interleave period (60 [m5ec
Control data D, which is composed of a 4-bit counter circuit that sequentially and cyclically increments a count value (consisting of )), is output from the system control circuit 6. When a start signal ST indicating the start of reproduction is output from the control circuit of the servo circuit 10 in response to NT, the frame address data latched by the reproduction frame address detection circuit 44 is loaded, and then the count value is updated. Start.

As a result, the reference frame address counter circuit 46
From the frame address data latched by the reproduced frame address detection circuit 44, reference frame address data FIEF, which is sequentially and cyclically counted up in an interleaving cycle, can be obtained.

The comparison circuit 48 compares the frame address data latched by the reproduction frame address detection circuit 44 and the reference frame address data F II! The comparison result with F is output to the drive signal generation circuit 50, thereby driving the capstan motor 32 so that the frame address data latched by the reproduction frame address detection circuit 44 matches the reference frame address data.

(Thus, in the long-time mode, the capstan motor 32 rotates the magnetic tape 20 in the forward direction during normal playback and in the reverse direction during reverse playback so that the magnetic tape 20 runs two track pitches in the interleave cycle. It can be run in any direction.

Therefore, with a simple configuration that only inverts the bits of the reproduction frame address data, the magnetic tape 20 can be reliably run in the NT servo state even in reverse reproduction, and reverse reproduction can be performed with a simple configuration.

(G2) Operation of the Embodiment In the above configuration, the capstan motor 32 drives the magnetic tape 20 so as to run two track pitches at the interleave period during recording.

As a result, the magnetic heads 18A and 18B form recording tracks at an interleaving period, and frame address data whose value increases cyclically is recorded on each recording track together with the digital audio signal DAU.

On the other hand, when reproducing the magnetic tape 20 recorded in the standard mode, the capstan motor 32 drives the magnetic tape 20 so as to run two track pitches at the interleave period, and at this time the tracking control circuit 36 outputs the tracking signal. Tracking is controlled based on the error signal.

As a result, in each magnetic head 18A and 18B,
It is possible to sequentially scan the recording tracks and output the reproduction signal S□, and demodulate the reproduction signal SIF to reproduce the digital audio signal DAU.

On the other hand, when reproducing the magnetic tape 20 recorded in the long-time mode, the capstan motor 32 drives the magnetic tape 20 so as to run two track pitches at the interleave period.

At this time, the rotating drum 22 rotates twice in an interleave period, and the repeatedly obtained reproduction data is selectively stored in the memory circuit 14 and then converted into a digital audio signal DAI.

On the other hand, the reproduction frame address data FAD is output to the servo circuit 10, and in the case of normal reproduction, the reproduction frame address data FAo is latched as is in the reproduction frame address detection circuit 44, and then the comparison circuit 44
It is compared with reference frame address data F□2.

As a result, the capstan motor 32 is driven and controlled so that the reproduced frame address data FAD matches the reference frame address data FIEF, and tracking control can be performed by NT servo.

On the other hand, in the case of reverse playback, after the playback frame address data FAll is bit-inverted in the OR circuit 42, it is latched in the playback frame address detection circuit 44, and the bit-inverted playback frame address data FAD is then latched in the playback frame address detection circuit 44. and reference frame address data F
A comparison result with □ is obtained.

Accordingly, in reverse playback, the playback frame address data Fao is bit-inverted and then processed in the same manner as in normal playback, thereby enabling tracking control by NT servo.

(G3) Effects of the Embodiment According to the above configuration, in reverse playback, the playback frame address data FAfl is bit-inverted and processed, and the playback frame address data FAD is bit-inverted with a simple structure. Can be played.

(G4) Other Embodiments In the above-described embodiments, a case has been described in which the playback frame address data is bit-inverted during reverse playback, but the present invention is not limited to this, and the playback frame address data during normal playback is may be bit-inverted.

In this case, the reference frame address counter circuit consisting of an up-counter circuit may be configured with a down-counter circuit.

Furthermore, in the above-described embodiment, the magnetic chip 1 recorded in the long-time mode is based on the playback frame address data.
Although the case of reproducing the magnetic tape 20 has been described, the present invention is not limited to this, and can be widely applied to the case of reproducing the magnetic tape 20 recorded in the standard mode.

Further, in the above-described embodiment, a case was described in which a rotating drum with a diameter of 30 (arm) was used, but the present invention is not limited to this. It can be widely applied when a rotating drum of 10 (ms) is used.

Furthermore, in the above-described embodiments, the case where digital audio signals are recorded and played back is described, but the present invention is not limited to the case where digital audio signals are recorded and played back.
When recording and reproducing various data, it can be widely applied to magnetic reproducing devices exclusively for reproducing.

H Effects of the Invention As described above, according to the present invention, by inverting the bits of the reproduced frame address data and comparing them with the reference frame address data, reverse reproduction can be performed with a simple configuration that only inverts the bits of the reproduced frame address data. A magnetic reproducing device can be obtained.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a digital audio chip recorder according to an embodiment of the present invention, and FIG. 2 is a block diagram showing a servo circuit. ■・・・Digital audio tape recorder,
8...Digital signal processing circuit, 10...
...Servo circuit, 32...Capstan motor, 40...--Demodulation circuit, 44...Reproduction frame address detection circuit, 46...Reference frame artless Counter circuit, 48... Comparison circuit, 50... Drive signal generation circuit. Agent Keiki Tanabe 1, Indication of the case 1990 Patent Application No. 6740 2゜ Name of the invention Magnetic reproducing device 3, Person making the amendment Relationship to the case Patent applicant address 6-7, Tokyo Illustrated Parts for Parts No. 35 Name (21
8) Sony Corporation Representative Norio Ohga 4, Agent 150 (Telephone 03-470-659)
1) Address: No. 5, 3-22 Jingumae, Shibuya-ku, Tokyo.
Target of amendment 6, Contents of amendment (1) In the specification, the phrase "OR circuit" in the following section has been changed to "
"Exclusive OR circuit" is corrected. Page 17, lines 15 and 19, page 19, lines 1-2, line 23
Page 17 lines.

Claims (1)

[Claims] In a magnetic reproducing device that reproduces a magnetic tape in which frame address data whose value increases or decreases in a cyclical manner is sequentially recorded on recording tracks together with predetermined data, the reproduced frame address is determined by demodulating the reproduced signal. demodulating means for extracting data; bit inverting means for bit inverting and outputting the reproduced frame address data during normal reproduction or reverse reproduction; and reference frame address data whose value sequentially increases or decreases at a predetermined period. a reference frame address data generating means to generate; reproduction frame address data or the bit-inverted reproduction frame based on a comparison result between the reproduction frame address data or the bit-inverted reproduction frame address data and the reference frame address data; 1. A magnetic reproducing device comprising: capstan motor driving means for driving a capstan motor so that address data matches the reference frame address data.