JPH03245304A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To transmit data without fail even in the case of any speed by switching the characteristic of each part corresponding to the transmission speed of the data. CONSTITUTION:When a recording mode is commanded, a system control part 18 controls a capstan motor 9 and a drum motor 6 through a motor control part 10 and travels or rotates a magnetic tape 7 and a drum 1 at the prescribed speed. A recording sound signal is inputted to an input/output circuit 11 and supplied to a recording signal processing circuit 12 after A/D conversion. The recording signal processing circuit 12 exerts processings such as interleave, addition of an error detection code and modulation, etc., upon the inputted digital signal, and the output signal is supplied through an amplifier 13 to a head 2 or 3 and recorded onto the magnetic tape 7. The motor control part 10 switches the characteristic of each circuit or each means, etc., respectively in the case of traveling the recording medium at normal speed or at high speed. Thus, the data can be exactly transmitted.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a magnetic recording/reproducing device suitable for use in R-DAT.

[Conventional technology]

In R-DAT, audio signals can be digitally recorded and reproduced on magnetic tape.

Since this is digital recording, this recording signal can be digitally copied onto another magnetic tape.

There is no deterioration in sound quality.

Therefore, in order to dub the data recorded on a given magnetic tape to another magnetic tape at high speed, or to shorten the backup time when used as a backup device for computer data, etc., a magnetic tape with twice the transfer speed has been developed. A recording device has been proposed.

[1iIll+Problem to be Solved by the Invention] However, if there is data (for example, audio data, etc.) that must be reproduced or recorded at fI normal speed, the conventional magnetic recording and reproducing apparatus In this case, recording and playback cannot be performed normally.

The present invention has been made in view of this situation, and is intended to enable data to be accurately transmitted not only at normal speeds but also at high speeds.

[Means to solve the problem]

The magnetic recording and reproducing apparatus of the present invention includes: a motor control means for controlling a motor that drives a recording medium and a motor that drives a head; a gain switching means for switching a servo gain in the motor control means; filter means for detecting a head tracking signal from a signal; filter characteristic switching means for switching the frequency characteristics of the filter means; waveform equalization means for equalizing the waveform of a reproduced signal; and frequency characteristics of the waveform equalization means. and a PL that extracts the clock from the reproduced signal.
L means, PLT, oscillation frequency switching means for switching the oscillation frequency of the means, signal processing means for processing signals recorded and reproduced on a recording medium, and system clock generation means for generating a system clock to be output to the signal processing means. and,
and clock switching means for switching the frequency of the system clock.

[Effect]

In the magnetic recording/reproducing apparatus configured as described above, the characteristics of each circuit, means, etc. are switched depending on whether the recording medium is running at a normal speed or at a high speed. Therefore, accurate data transmission becomes possible.

〔Example〕

FIG. 2 is a block diagram showing the configuration of an embodiment of the magnetic recording/reproducing apparatus of the present invention.

On the drum 1, recording heads 2 and 3 and reproduction heads 4 and 5 are arranged at an angle of 6180 degrees. Heads 2 and 5 have positive azimuth angles, and heads 3 and 4 have negative azimuth angles. Then, the signal recorded by head 2 (3) is transferred to head 5.
(4) The latter is placed a predetermined distance apart from the former in the direction of the rotation axis of the drum 1 so that it can be immediately reproduced.

Columns 1 to 1 are rotated by a drum motor 6, and a capstan 8 for running a magnetic tape 7 as a recording medium is rotated by a capstan motor 9. The rotation of the drum motor 6 and capstan motor 9 is controlled by a motor control unit 10.
controlled by

The recording data is input to the recording signal processing circuit 12 via the input/output circuit 11 and is processed. The recording data output from the recording signal processing circuit 12 is sent to the head 2 via the amplifier 13.
Further, the reproduced RF signal reproduced by the head 4 or 5 is input to the waveform equalizer 15 via the amplifier 14 and is equalized by 5. The output of the waveform equalization section 15 is supplied to the reproduced signal processing circuit 17 via the PLL section 16. The signal processed by the reproduced signal processing circuit 17 is outputted to a circuit (not shown) via the input/output circuit 11.

The system clock generator 19 generates a system clock and outputs it to the recording signal processing circuit 12 and the reproduction signal processing circuit 7. For example, the system control section 18 consisting of a microcomputer etc. includes the motor control section 10,
It outputs identification signals for switching the characteristics of each section to the waveform equalization section] 5, PLL section 16, system clock generator 19, etc.

Next, its operation will be explained.

When the recording mode is commanded, the system control unit 1
8 controls a capstan motor 9 and a drum motor 6 via a motor control section 10 to cause the magnetic tape 7 and drum 1 to travel or rotate at a predetermined speed.

The recorded audio signal is input to the input/output circuit 11, A/D converted, and then supplied to the recorded signal processing circuit 12. The recording signal processing circuit 12 performs processing such as interleaving, addition of an error detection code, modulation, etc. to the input digital signal. A system clock necessary for these processes is supplied to the recording signal processing circuit 12 from a system clock generator 19.

The signal output from the recording signal processing circuit 12 is sent to the amplifier 1.
3 to the head 2 or 3, and the magnetic tape 7
” recorded in 2.

On the other hand, when the reproduction mode is commanded, the RF signal reproduced from the head 4 or the magnetic tape 7 is transmitted to the amplifier 14.
The signal is input to the waveform equalization section 15 via.

The waveform equalization unit 15 equalizes the input RF multiplied signal waveform,
It is output to the PLL section 16. The clock component is extracted from the input signal to the PLL section 1, and a continuous taro clock is generated. The reproduced signal processing circuit 17 reads the signal supplied to the PLL section 1 and reproduces the data using the clock also supplied therefrom.

The reproduced data is output to the input/output circuit 11, subjected to D/A conversion, and then supplied to a circuit (not shown). Further, the code read by the reproduction signal processing circuit 17 is output to the system control section 18.

A system clock necessary for processing in the reproduced signal processing circuit 17 is supplied from a system clock generator 19.

Next, the speed switching operation will be explained.

When a command for a normal speed or a speed twice the normal speed is input, the system control unit 18 transmits an identification signal corresponding to the command to the motor control unit 10 and the waveform equalization unit 1.
5. I) LL section 6. System clock generator 19
Output to.

FIG. 1 shows the configuration of an embodiment of a motor control section 10 (motor control means).

As shown in the figure, the RF multiplied signal output from the amplifier 14 is input to filters 2], 22 (filter means). This filter 2.1.22 is for detecting a tracking ATF signal included in the reproduced RF signal. The filter 21 includes the magnetic tape 7 and the drum 1.
is the normal speed (8.15n+m/s, 2000
rpm), the frequency characteristics are set to be optimal for detecting the ATF signal. On the other hand, the filter 22 allows the magnetic tape 7 and the drum 1 to operate at twice the normal speed (6.3
mm/s, 4000 rpm), AT
The frequency characteristics are set to be optimal for detecting the F signal.

The switch 23 (filter characteristic switching means) is switched to the filter 21 side for normal speed and to the filter 22 side for double speed, respectively, in response to the identification signal. The motor control circuit 24 is connected to the AT input via the switch 23.
Tracking servo is executed based on the F signal.

Also, the gain of this servo is optimized for normal speed and double speed.

Dedicated time constant circuits 25 and 26 are provided for each, and a switch 27 (gain switching means) is provided corresponding to the 1 mm special number.
are switched and one of them is selected.

In the waveform equalization section 15, as shown in FIG. 3, a waveform equalization circuit 44 (waveform equalization means) is provided with filter time constant circuits 41 and 42 for setting appropriate frequency characteristics. ing. The time constant circuit 41 is selected at normal speed, and the time constant circuit 42 is selected at double speed by a switch 43 (equalization characteristic switching means) in response to the identification signal.

Alternatively, the waveform equalization section 15 (waveform equalization means) may be configured as shown in FIG.

In this embodiment, a reproduced RF signal is outputted to a coefficient unit 53 and a delay line 52 via a low-pass filter 51. The coefficient [53 also includes the delay line 52
A signal reflected by and delayed by twice the amount of delay is input.

The coefficient unit 53 multiplies the input signal by a predetermined coefficient and outputs the result to the adder 54. Further, the delay line 52 delays the input signal by a predetermined time uIJ and outputs the delayed signal to the adder 54. The adder 54 connects the output of the coefficient unit 53 and the delay line 52.
The output of the PLL section 1 is added to the output of

The delay time in the delay line 52 is switched by a switch 55 (equalization characteristic switching means) corresponding to the Ill times signal.

In this way, even if the amount of delay is switched between normal speed and double speed, it is possible to achieve optimal frequency characteristics in each case.

FIG. 5 shows the frequency characteristics set in the waveform equalizer 15 in this way. In the case of double speed, a higher frequency band is set than in the case of normal speed.

FIG. 6 shows the structure of one embodiment of the L L section 16.

In this embodiment, the input iL from the waveform equalization section 15 is
Synchronized with the clock component included in the reproduced RF signal, P
The L L circuit 61 (PLL means) extracts the clock. Then, the output of the voltage controlled oscillator (VC○) built in the PLL circuit 64 is transmitted to the frequency dividing circuit 6
2 (oscillation frequency switching means) and after being divided,
PI, is supplied to the phase comparator built in the 7 circuit 61. The frequency division ratio of this frequency dividing circuit 62 is switched in response to the identification signal.

FIG. 7 shows the configuration of one embodiment of the system clock generator 19.

The system clock generator 19 is a clock oscillator 3
1 (system clock generation means), and its output is divided by a predetermined frequency division ratio and output as the system 11 clock to the recording signal processing circuit 12 and the reproduction (No. 1 processing circuit 32 (signal processing means)). The frequency division ratio switching circuit 32 (crotter switching means) is configured to switch the frequency division ratio in the frequency division ratio switching circuit 32 in response to the identification signal.

It should be noted that it may be generated in response to the Fa-specific multiplied signal, a manually input playback speed switching signal, or a specific (i number (for example, I) A TΔII)) may be detected from the playback signal and its Depending on the detection result, it may be possible to automatically switch between normal speed when the data is audio signal data and double speed when the data is other data.

〔Effect of the invention〕

As described below, according to the magnetic recording and reproducing apparatus of the present invention,
Since the characteristic 1 of each part is changed according to the data transmission speed, data can be reliably transmitted at any speed.

[Brief explanation of drawings]

1 is a block diagram showing the configuration of an embodiment of the motor control section in the embodiment shown in FIG. 2; FIG. 2 is a block diagram showing the configuration of an embodiment of the magnetic recording/reproducing apparatus of the present invention; FIG. and FIG. 4 is a block diagram showing the configuration of an embodiment of the waveform equalization section in the embodiment shown in FIG. 2, and FIG. 5 is a frequency characteristic diagram showing the frequency characteristics in the embodiment shown in FIGS. 3 and 4. 6th
The figure is a block diagram showing the configuration of one embodiment of the PLL section in the embodiment of FIG. 2, and FIG. 7 is a block diagram showing the structure of one embodiment of the system clock generator in the embodiment of FIG. be. 1 ・Dora 11.2 to 5 ・Hera 1-16...Dora 1
1 Motor, 8 Capstan, 9 Capstan motor, 10 Motor control circuit, 12 Recording signal processing circuit, 15 Waveform equalization unit, 16...)) L 1
．． , section, 17... Reproduction signal processing circuit, 18... System 11 controller 1 to row 12 control section, 19... System clock generator.

Claims (1)

[Claims] a motor control unit that controls a motor that drives a recording medium and a motor that drives a head; a gain switching unit that switches a servo gain in the motor control unit; and tracking of the head from a reproduction signal reproduced from the recording medium. a filter means for detecting a signal of interest, a filter characteristic switching means for switching the frequency characteristic of the filter means, a waveform equalization means for equalizing the waveform of the reproduced signal, a frequency characteristic of the waveform equalization means, etc. and P for extracting a clock from the reproduced signal.
LL means, oscillation frequency switching means for switching the oscillation frequency of the PLL means, signal processing means for processing signals recorded and reproduced on the recording medium, and system clock generation for generating a system clock to be output to the signal processing means. and clock switching means for switching the frequency of the system clock.