JPH0722767Y2 - DAT recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to a DAT digital recording device, and more particularly to a DAT digital recording device that is effective when used during digital copying and is widely compatible with recording sources.

(Prior Art) FIG. 2 is a block diagram showing a configuration of a conventional DAT (digital audio tape).

The information recorded on the magnetic tape 12 is detected (read) by the magnetic head MHD of the drum 11 as a magnetic flux change of the magnetic tape 12, amplified by the RF amplifier 10, and then sent to the signal processing circuit 8.

In the signal processing circuit 8, a random access memory (RAM)
Using the information stored in 9, the signal transmitted from the RF amplifier 10 is subjected to a predetermined conversion (encoding, decoding) process such as known decoding, and a reproduced digital audio signal DADT converted and reproduced is obtained. Is output.

The signal DADT is converted into an analog signal by the D / A converter 6, the unnecessary components are removed by the low-pass filter (LPF) 5, and the signal DADT is output from the output terminal LINE OUT.

On the other hand, when the recording operation is performed, the operation reverse to the above operation is performed.

That is, the input analog signal input from the input terminal LINE IN is converted into a digital signal in the A / D converter 3 after the unnecessary components are removed by the low pass filter (LPF) 1, and the input terminal of the selector 4 Supplied to T ₂ .

In addition, the digital input signal RX is a digital interface.
At 22, the demodulated digital audio data signal RXDT is demodulated based on a predetermined format and the input terminal T of the selector 4
₁ , the control signal DCO is supplied to the system control circuit 23.

The selector 4 receives the input terminal T in response to the switching signal S (corresponding to the recording mode) from the system control circuit 23.
_The signal ADDT or RXDT supplied to ₁ and T ₂ is switched to the signal processing circuit 8 and output.

In the signal processing circuit 8, the received signal ADDT or
The RXDT is subjected to predetermined conversion such as encoding and sent to the RF amplifier 10. The signal amplified by the RF amplifier 10 is
It is recorded on the magnetic tape 12 via the magnetic head MHD of the drum 11.

The system control circuit 23 is a circuit for system-controlling the above-mentioned components of the DAT, and generates various signals in addition to the recording mode designation signal S. For example, the system control circuit 23 receives a signal which is set (designated) by the operation of the key 25, transmits / receives a necessary signal to / from each of the above components, and the display circuit 24 displays each operation state. To perform.

The servo circuit 13 responds to operations such as recording / playback, fast forward (FF), and rewinding (REW) set by operating the key 25.
In response to the command signal from the system control circuit 23,
Each of the drum motor 15, the capstan motor 17, and the reel motor 19 is drive-controlled via the drum driver 14, the capstan driver 16, and the reel driver 18.

The above system operation is performed by various signals generated in the signal processing circuit 8 based on the master clock MCK generated from the crystal oscillation circuit 21 or the clock RXCK extracted by the digital interface circuit 22 from the signal RX.

That is, the selector 20 is provided and its input terminals T ₁ and T ₂
Are supplied with clocks RXCK and MCK, respectively, and one of them is switched by the switching signal S from the system control circuit 23 and sent to the signal processing circuit 8.

When the information of the category code / digital copy bit in the channel status included in the signal DCO is in a state where digital recording is prohibited (for example, when the category code is DAT and the digital copy bit is prohibited), the system control circuit 23 Prohibits DAT recording operation.

(Problems to be solved by the invention) In the recording operation of the above-mentioned conventional DAT, when the category code and the digital copy bit in the digital input signal include information for prohibiting digital recording ( When the category code is DAT and the digital copy bit is prohibited), there is a problem that the recording operation is stopped or prohibited. That is, the sampling frequency of the digital signal is 32 KHz, like the BS tuner,
Optimal operation is impossible for sources that switch at 48 KHz.

Therefore, the purpose of this invention is to deal with the nature of the recorded source even when the digital input signal contains the information of the category code / digital copy bit indicating the state where digital recording is prohibited. The purpose is to provide a DAT recording device that can be set to an optimum operating state.

(Means for Solving the Problems) In order to solve the above-mentioned problems, a DAT recording apparatus according to the present invention is a DAT recording apparatus that digitally records a digital signal on a tape. Detecting means for detecting a state where digital recording is prohibited from the information of the copy bit, converting means for converting the digital signal into an analog signal and then converting the converted signal into a digital signal, and digital recording by the detecting means. When a prohibited state is detected, setting means for arbitrarily switching and setting an operation of making the recording stand-by in a recording paused state or recording the digital signal obtained by the converting means on the tape, It is equipped with.

(Operation) In the DAT recording apparatus according to the present invention, when the state in which the digital recording is prohibited is detected from the information of the category code and the digital copy bit in the recording digital signal, the operation is stopped in the recording pause state or the digital recording is performed. After the signal is converted into an analog signal, the converted signal is converted into a digital signal, and the obtained digital signal is arbitrarily set to be in a state of being recorded on the tape.

(Example) Next, this invention is demonstrated, referring drawings.

FIG. 1 is a block diagram showing an embodiment of a DAT recording apparatus according to the present invention. In FIG. 1, the same reference numerals as those in FIG. 2 indicate the same constituents.

In the embodiment of this invention, two selectors 2 and 7 are added to the configuration shown in FIG. That is, selector 2
Is provided between the low-pass filter (LPF) 1 and the A / D converter 3, and the output of the low-pass filter (LPF) 5 and the low-pass filter are respectively connected to its input terminals T ₁ and T _2. (LPF) 1
Is supplied, and one of the signals is selectively output by the switching signal S from the system control circuit 23.

Further, the signal RXDT from the digital interface circuit 22 and the signal DADT from the signal processing circuit 8 are respectively supplied to the input terminals T ₁ and T ₂ of the selector 7, and either of the signals is similarly a switching signal. It is selected by S and output to the D / A converter 6.

That is, the digital input signal RX is demodulated in the digital interface 22, separated into the digital audio data RXDT and the control signal DCO, and output to the signal processing circuit 8 and the system control circuit 23, respectively.

The system control circuit 23 receives the category code / digital copy bit in the channel status included in the signal DCO, and determines whether the digital copy is permitted or prohibited.

When the information of the category code and digital copy bit in the channel status included in the signal DCO is in a state where digital recording is enabled (for example, the category code is DB
S, if the digital copy bit is permitted), the selector 4 selectively outputs the signal of the input terminal T ₁ , and the selector 20 selectively outputs the signal of the input terminal T ₁ . Digital input signal R
X is demodulated by the digital interface circuit 22, and the signal R
It is input to the signal processing circuit 8 as XDT and recorded on the magnetic tape 12 via the RF amplifier 10 and the magnetic head MHD.

In the reproduction, the analog signal and the digital signal are respectively output from LINE OUT and TX through the process reverse to the above. That is, the signal read from the magnetic tape 12 is output to the LINE OUT through the RF amplifier 10, the signal processing circuit 8, the selector 7, the D / A converter 6 and the low pass filter 5, and the output of the signal processing circuit 8.
DADT is output to TX via the digital interface 22.

Next, if the category code / digital copy bit in the channel status included in the signal DCO is in a state where digital recording is prohibited (for example, when the category code is DAT and the digital copy bit is prohibited), switch The following three operating states are selected and selected depending on the position of the switch 25a. That is, (1) When the CD DAT operation is in the recording standby state (REC PAUSE) and the prohibition of digital recording is released, the recording operation is started.

(2) Selector 2 selectively outputs the signal at input terminal T ₁ ,
The selector 4 selectively outputs the signal of the input terminal T ₂ , the selector 7 outputs the signal from the input terminal T ₁ , and the selector 20 selectively outputs the signal of the input terminal T ₁ to output the signal RXD.
T is input to the D / A converter 6 via the selector 7.

The analog signal converted and output by the D / A converter 6 is an LPF.
Unwanted band components are removed at 5 and pass through selector 2 for A / D
After being converted into a digital signal by the converter 3, it is input to the signal processing circuit 8 via the selector 4.

The signal processing circuit 8 performs the above-described processing and records a signal on the magnetic tape 12 via the RF amplifier 10 and the magnetic head MHD.

(3) Selector 2 uses terminal T ₂ and selector 4 uses terminal T ₂
, The selector 7 selects an arbitrary signal (normally T ₂ ), the selector 20 selects the terminal T ₂ and performs a normal recording operation from the LINE IN (an analog signal obtained by demodulating the signal RX and an analog signal input from the LINE IN). If the signals are equivalent).

In the embodiment described above, the D / A converter of the conventional circuit shown in FIG. 2 is also used as the LPF, but a separate D / A converter and LPF are added so that the digital interface circuit 22 can be used at all times.
The selector 7 can be omitted by adopting a configuration in which the digital audio data RXDT from is converted to D / A and the obtained analog signal is input to the A / D converter 3 via the selector 2.

It is also possible to send a signal indicating that the category code / digital copy bit in the channel status included in the signal DOC prohibits digital recording to the outside to perform the conversion process. That is, if it is guaranteed that the analog signal input to LINE IN is equivalent to the analog signal demodulated and D / A converted from the signal RX, the selector 2
And 7 can be omitted.

Further, in the above embodiment, the changeover switch 25a
Although the above three operations are switched by the above, the switching operation can be automatically performed by the information such as the category code and the digital copy bit in the channel status included in the signal RX.

(Effect of Device) As described above, in this device, the optimum recording operation state can be set according to the input signal source.
For example, RE for a source such as a BS tuner whose digital signal sampling frequency switches between 32KHz and 48KHz.
You can select the operation like C → PAUSE → REC.

Also, if the source that can be digitally copied and the prohibited source are mixed in the tape with DAT etc., the source that can be digitally copied is copied as it is. → You can select the operation to re-convert to digital and continue recording. Therefore, it can widely correspond to the nature of the recording source,
Even if any category code / digital copy bit is input, for example, even if the condition that digital recording is prohibited in the information of the category code / digital copy bit in the channel status included in the signal RX, the recording operation is stopped. Alternatively, the recording can be performed on the magnetic tape without being prohibited, and the user does not have to worry about the prohibition of recording. Further, the circuit configuration of the present invention is simple because it is sufficient to add a selector.

[Brief description of drawings]

FIG. 1 is a block diagram showing the construction of an embodiment of a DAT recording apparatus according to the present invention, and FIG. 2 is a block diagram showing the construction of a conventional DAT recording apparatus. 1,5 ...... Low pass filter (LPF), 2,4,7,20 ...... Selector, 3 ...... A / D converter, 6 ...... D / A converter, 8 ...... Signal processing circuit, 9 ...... RAM, 10 …… RF amplifier, 11 …… Drum, 1
2 ... magnetic tape, 13 ... servo circuit, 14 ... drum driver, 15 ... drum motor, 16 ... capstan driver, 17 ... capstan motor, 18 ... reel driver, 19 ... read motor, 21 ... Crystal oscillator, 22 ... Digital interface, 23 ... System control circuit, 24 ... Display circuit, 25 ... Key, 25a ... Changeover switch.

Claims (1)

[Scope of utility model registration request] 1. A DAT recording device for digitally recording a digital signal on a tape, a detection means for detecting a state in which digital recording is prohibited from the category code and digital copy bit information in the digital signal; After converting the signal to an analog signal, a converting unit that converts the converted signal into a digital signal, and when the detecting unit detects a state in which digital recording is prohibited, the recording unit is put in a recording paused state, or, A DAT recording apparatus, comprising: setting means for arbitrarily switching and setting an operation of recording the digital signal obtained by the converting means on the tape.