KR950013830B1 - Solo copy control circuit - Google Patents

Abstract

a digital interface unit for digital in or digital out; a unit for decoding the copy bit of a channel status signal and a specific bit of a category code if a digital audio data which has been processed according to a solo copy format is input via the digital interface unit; a unit for generating an ID representing copy permission or copy prohibition according to the decoding result and controlling a recording unit to determine whether or not to output the record data according to the ID; a unit for detecting ID from the data reproduced from the digital audio tape; a unit for outputting information for setting the copy bit or a specific bit of the category code to a predetermined state via the digital interface unit; and a unit for generating a timing slot of a specific bit of the category code and a timing slot of the copy bit.

Description

Solo copy control circuit

1 is a digital audio channel status format diagram used in the present invention.

2 is a block diagram of a solo copy control circuit during reproduction according to the present invention.

3 is a block diagram of a solo copy control circuit in recording according to the present invention.

* Explanation of symbols for main parts of the drawings

31: playback unit 32: ID6 detection unit

33: solo copy processing unit 34, 41: digital interface unit

35: counter decoder 42: channel state decoder

43: ID6 generating section 44: microcomputer

45: record

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape duplication circuit in a digital audio tape recorder, and more particularly to a solo copy control circuit.

In general, a digital signal can be preserved with little change in data even after multiple copies. Therefore, if an unlimited copy of a digital audio tape (hereinafter referred to as DAT) is granted, many people rely on the copy and the DAT seller may not be able to obtain an adequate level of sales profit.

In order to solve this problem, a solo copy format has emerged. In this case, a single copy is possible when a pre-recored tape is a source. It is impossible to recopy to tape and can be ranged from source to source.

Accordingly, an object of the present invention is to provide a solo copy control circuit capable of detecting and recording ID6 during recording and recording of a tape using a solo copy format, and detecting and recording copy bits and category codes to implement solo copying.

In order to achieve the above object, the present invention provides a digital audio tape recorder having recording means, in which digital interface means for digital in or out, and digital audio data processed according to a solo copy format are inputted through the digital interface means. Means for decoding the copy bit of the channel status signal and the specific bit of the category code, and generating an ID ID6 indicating whether to permit or prohibit copying according to the decoding result therebetween, so that the recording means generates an ID according to the ID. Means for controlling whether or not to output recorded data; means for detecting an ID in data reproduced from a digital audio tape; and a specific bit of a copy bit or a category code according to a detection state of the ID and a predetermined control signal. The digital information to be set to the state. Means for outputting through an interface means, and means for generating a timing slot of the copy bit and a timing slot of a specific bit of the category code.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

First, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals have the same reference numerals as much as possible even if displayed on different drawings. In addition, in the following description, many specific details such as components of a specific circuit are shown, which are provided to help a more general understanding of the present invention, and the present invention may be practiced without these specific details. It will be obvious to those of ordinary skill in Esau. In the following description of the present invention, detailed descriptions of related known functions or configurations will be omitted if it is determined that the detailed description of the present invention may unnecessarily obscure the subject matter of the present invention.

DAT has user-friendly functions such as song number display, time display, and various search functions to find and play the head of the song. This is possible because the microcomputer can read the subcode information recorded on the tape. . There are two types of subcodes in DAT. One is a control signal necessary for reproducing a main signal (music signal) such as sampling frequency, number of channels, and the other is an additional signal such as song number, time, image signal, and the like. The former is called an ID (iendtification), and among those related to the main signal, a main-ID and an additional signal are called a subcode ID. ID6 used in the present embodiment is a subcode of the main-ID, which is a code designed to limit the copying during DAT standardization, that is, to indicate permission or prohibition of digital copying in the DAT meeting.

Figure 1 shows the digital audio channel status format used in the present invention. There are four control signals V, C, U, and P in the format of the interface signal between digital audio devices. Of these, the C signal, or channel status, is directly related to the present embodiment. This channel status signal is processed in units of 192 frames (1 block), and information about the state of the channel (audio sample word length, pre-emphasis, sampling frequency, time code, alphanumeric source, etc.) is shown in FIG. Transmit with the allocated bits as one.

Part of the allocation of the bits associated with this embodiment is the 'control' and the 'category code'. In the 'control', the 0th bit is for home use, the 1st bit is the content of the transmission information (voice data or digital data), the 2nd bit is for digital copy permission or prohibition, and the 3rd and 4th bits are for an amphasis relationship. Display. In addition, the eighth to fifteenth bits constituting the 'category code' indicate two-channel DAT when 11000000, two-channel CDP when 10000000, and two-channel PCM encoder / decoder when 01000000.

2 is a configuration diagram of a solo copy control circuit during reproduction according to the present invention, which includes an ID6 detection unit 32 for detecting ID6 by decoding digital data reproduced from a tape via the reproduction unit 31, and the ID6 detection state and A solo copy processor 33 for outputting data (information) for setting a copy bit of a channel status signal or a fifteenth bit of a category code according to a predetermined control signal to a predetermined state, and the solo copy processor 33 Outputs the copy bit or the fifteenth bit-related data from the digital output terminal Tx and outputs the solo copy processing unit 33 and the fifth and sixth control signals W5 and W6, respectively. Under the control of the digital interface unit 41 and the digital interface unit 34 to exchange data, the solo copy processing unit 33 transmits the timing slot W3 of the copy bit and the tie of the fifteenth bit. It consists of a counter decoder 35 for generating a slot (W4).

3 is a configuration diagram of a solo copy control circuit during recording according to the present invention, wherein digital audio data processed according to the solo copy format is input through the digital interface unit 41 and processed according to the solo copy format. to be.

A channel status decoder 42 which decodes the fifteenth bit of the copy bit and the category code, and ID6 having decided whether to permit or prohibit copying according to the decoding result in a predetermined state, and causes the recording unit 45 to generate the generated ID6 Is composed of an ID6 generating section 43 for determining whether or not to output the recording data RDATA.

Here, the recording unit 45 may be configured to be controlled by the microcomputer 44 that recognizes the operation state of the ID6 generation unit 43.

First, the solo copy format of the DAT is explained as follows.

A. The DAT-category code in the C-channel of the digital output signal is output as follows.

-ID6 "11" (11000001)

-ID6 "10" or "00" (11000000)

B. Copy bit of C-channel of digital output signal is output as follows.

-ID6 "00": Set the copy bit to enable (x1xxx).

-ID6 "10" or "11": copy bit is disabled (x0xxx).

C. If the copy bit in the digital input signal is allowed (x1xxx), write ID6 as "00" on the DAT-tape.

D. If copy bit of digital input signal is prohibited (x0xxx), recording is prohibited except in the case of E. below.

E. When the copy bit is prohibited (x0xxx), recording is possible when the category code is (11000001), and recording is prohibited when (11000000). However, recording is done with ID6FMF "10".

F. ID6 is recorded as "11" on commercially available pre-recorded DAT-tape.

Referring to items A and B in the solo copy format, when ID6 is "11" during playback, the 15th bit of the 8th to 165th category codes as shown in the channel status format shown in FIG. Make it "1" and make it "0" when it is "10" or "00". When ID6 is "00", the second bit, which is a copy bit, is set to "1", and when the ID6 is "10" or "11", it is set to "0".

Therefore, in FIG. 2, the ID6 detection unit 32 decodes ID6 of data read from the tape through the playback unit 31, and activates the first control signal W1 when ID6 is "00". As a result, the solo copy processing unit 33 outputs 1 to the digital interface output terminal Tx through the digital interface unit 34 to set the copy bit to "1". In addition, when ID6 is "11", the ID6 detection unit 32 activates the second control signal W2 to cause the solo copy processing unit 33 to pass through the digital interface unit 34 through the digital interface unit 34 as described above. By controlling to set the 15th bit of the category code of the channel status signal to "1" through. In addition, when ID6 is detected as "10" or "01" (reserved), both the first and second control signals W1 and W2 are not activated. As a result, the copy bit and the fifteenth bit are set to "0" to satisfy the A and B items of the above-described solo copy format.

At this time, the counter decoder 35 generates the third and fourth control signals W3 and W4 to the solo copy processing unit 33 under the control of the digital interface 34, and the third control signal W3. ) Is a timing slot of the second bit and the fourth control signal W4 is a timing slot of the fifteenth bit. In addition, the fifth control signal W5 output from the digital interface unit 34 to the solo copy processing unit 33 is a signal that is activated when data (channel status signal) is sent to the digital interface output terminal Tx. The sixth control signal W6 is for setting the C bit according to the result of processing by the solo copy processing unit 33 by the fifth control signal W5. Also, if ID6 of the prerecorded tape is set to "11", only one copy is possible.

FIG. 3 shows a configuration of a circuit for processing digital audio data processed according to the above description in accordance with a solo copy format when the digital audio data is input through the digital interface input terminal Rx.

If the second bit of the signal received by the channel status decoder 42 is set to "1", ID6 is set to "00" in the ID6 generator 43 to permit copying. If the second bit is set to "0", the channel status decoder 42

Checks the fifteenth bit of the category code of the received signal. At this time, if the fifteenth bit is " 0 ", the ID6 generation unit 43 sets the ID6 to " 10 " to prevent the digital copy from being abnormal and to prevent the recording data RDATA from being output. Is activated by the microcomputer 44). On the other hand, if the fifteenth bit is "1", ID6 is set to "10" and the recording data RDATA is sent.

After all, when the second bit is set to "0", the digital copy is impossible when the 15th bit of the category code is "0", and when the "1" is "1", ID6 is set to "10". At this time, if the reproduced signal is reproduced, digital copy is impossible in the circuit configured as the third diagram.

The present invention as described above has the advantage of being able to reduce the disadvantages of the seller to some extent by specifying the copy amount of the tape by implementing the DAT solo copy circuit.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications may be made without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the scope of the following claims, but also by the equivalents of the claims.

Claims (1)

A digital audio tape recorder having recording means, comprising: digital interface means for digital in or out, and digital bit data and category of a channel status signal when digital audio data processed according to a solo copy format is input through the digital interface means. Means for decoding a specific bit of code and means for generating an ID (ID6) indicating whether to permit or prohibit copying according to the decoding result, and controlling the recording means to determine whether to output the record data according to the ID. And means for detecting an ID of data reproduced from the digital audio tape, and information for setting a specific bit of a copy bit or a category code to a predetermined state according to the detection state of the ID and a predetermined control signal. Means for outputting through means And means for generating a timing slot of the copy bit and a timing slot of a specific bit of the category code.

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