JPS63213189A - Data recorder for vtr - Google Patents

Abstract

PURPOSE:To retrieve an absolute address, by recording a time information data and a program number data at every constant time alternately. CONSTITUTION:In a recording mode, a microcomputer 12 stores a signal to be recorded immediately in a data memory when it is judged as an index signal, and stores the program number data by a numeral from a character key on a keyboard 18 or in an operating part when the signal is judged as the program number data. Afterwards, when a mode is judged as a reproducing mode, it is judged whether a rewrite key 27 is depressed or not. The microcomputer 12, at the time of detecting the depression of the key 27, makes a read and write circuit 13 perform an operation to vary the duty cycle of a control pulse.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a data recording device for a VTR, and in particular to a data recording device for a VTR (
The present invention relates to a recording device that records data on a magnetic tape, such as position information, on a magnetic tape on which video signals and audio signals are recorded and reproduced by a magnetic recording and reproducing device.

Conventional Technology The applicant has previously filed Japanese Patent Application No. 61-66159, based on data regarding the position information and arbitrary comment information of the magnetic 7-band used in home VTRs.
A VT configured to vary the control pulse decoupage recycle, record it on a control track, play it back and display it, and enable random access.
We proposed an R data recording and reproducing device.

According to this proposed VTR data recording and reproducing device,
Multiple types of data as appropriate m Jfl! Because it records and plays back on the control track of the magnetic tape using L, it can be constructed at a lower cost than a VTR that records and plays back SMPTE time code, and it is also compatible with Utility Model Publication No. 57-34633.
Compared to the conventional VTR described in the issue, it has superior features such as being able to freely record any information with extremely simple operations, and also allowing random access, allowing for a wide variety of uses. .

However, the control pulse has a period of one frame (1/
The data transmission bit rate is extremely low at 30 bits/second, and the data transmission bit rate is extremely low at 30 bits/second. In the above-mentioned proposed device that records data on a control track, random information data having no continuity is recorded on the control track. For this reason, if a dropout occurs when one unit is read, there is usually no correlation with data read in the past, so the dropout cannot be corrected and malfunctions occur. In particular, in the case of a VTR, such as forwarding and rewinding, tape running is unstable, so dropouts are likely to occur, and there is a high risk of malfunction.

Therefore, in Japanese Patent Application No. 61-66162, the present applicant previously proposed a method to effectively record VTR data despite the low bit rate and to prevent malfunctions even if dropouts occur. We proposed a method for recording and reproducing data on a VTR.

This VTR data recording method involves appropriately selecting multiple types of data such as magnetic tape position information and comments on recorded information content, and varying the duty cycle of a control pulse with a constant period according to the value of the selected data. A method for recording multiple types of data on a control track using the same signal format in which the data is arranged between 62 adjacent headers of a fixed pattern, together with an identification signal indicating the data type, or alone. The content data is repeated three or more times and sequentially recorded on the control track. In addition, in this VTR data recording and reproducing method, the data recorded on the control track as described above is detected and reproduced from the duty cycle of the reproduction control pulse, and among the data, data with the same content is reproduced. The data values that are successively reproduced the same number of times as the number of repeated recordings are compared, and two or more data values that are the same are reproduced and output as true data values.

As a result, even though the bit rate is low, arbitrary comment (character) information, 1st address information, and special function information can be effectively recorded, and even if there is a dropout of the playback control pulse, malfunctions due to it can be prevented. can be significantly reduced. In addition, even if data is accidentally erased when rewriting data, it can be detected by determining the signal between the headers and malfunctions can be prevented. However, since identification signals are provided before and after the header, it is possible to immediately detect text information not only when fast forwarding but also when rewinding, and the detection circuit etc. can be easily configured. In addition, since multiple types of data are selectively recorded on the control track instead of the video signal track, there are many advantages that make it extremely easy to turn on and off the on-screen without damaging the video or audio signal. It has characteristics.

Problems to be Solved by the Invention However, even if, for example, time (position) information on a magnetic tape is recorded continuously or at fixed time intervals and an attempt is made to search for the absolute address (position) of the magnetic tape, the time information etc. Since the address may be rewritten, there is a problem that there is no guarantee that the absolute address search will be performed immediately and reliably. Further, when a plurality of programs are recorded on a magnetic tape, it would be convenient if the position on the magnetic tape could be searched based on time information and program number information.

Therefore, the present invention makes it possible to record a large amount of data by alternately recording time information data and program number data on a control track of a magnetic tape at regular intervals, and also to reliably search for an absolute address. VTR that can be used
The purpose is to provide a data recording device.

Means for Solving the Problems The data recording device for a VTR according to the present invention is capable of recording 1il' of data.
When recording on a control track by varying the duty cycle of a control pulse of a constant period according to j, time information data T and block 1 gram number data P are recorded (for example, in units of blocks to which a header H is added). As shown in FIG. 1(A), the recording is performed alternately at regular intervals.

The action time information data T indicates the time based on the signal recording start position on the magnetic tape or the start position of each program, and is not rewritten even when data is replaced. On the other hand, the program program number data P consists of an extension code that essentially indicates the type of data, such as a program code that indicates the program number. When rewriting data, by replacing this extension code,
You can change the type of data for one click. Since the time information data T has continuity with each other, even if the time information gator T is missing due to dropout or the like, the missing time information can be interpolated based on the relationship before and after. Also,
As for the program number data P, since the same program number is repeatedly recorded within the same program, even if one program number data P is missing due to dropout or the like, it can be easily interpolated.

Embodiment FIG. 2 shows an embodiment of the signal format of data recorded by the apparatus of the present invention. The present invention is an apparatus that appropriately selects a plurality of types of data and records them on a control track on a magnetic tape by varying the fl-ti cycle of a control pulse having a constant period according to the value of the selected data. Figures 2 (Δ) and (B) show signal formats of two types of data.

FIG. 2(A) shows a signal format of one embodiment of the time information data T. In the figure, H is a 9-pin 1-header,
The two most significant bits and the two least significant bits indicate the running direction of the magnetic tape, and the five bits between them are fixed bits.

For example, the fixed 5 bits in the header "1" are MlllJ, and the values of the most significant 2 bits and the lowest 2 bits are r10J.

roOJ indicates that the running direction is positive (for example, in FF mode), and [00J, roI
J indicates that the running direction is the opposite direction (for example, during REW). The 16-bit time information data T indicates the time from the start position of the program within one program.

It consists of a code representing minutes and 2 seconds. The time information data T is
The first two bits indicate the hour, and the next three bits indicate the minute.
The next 4 bits indicate the "-" digit of the minute, the next 3 bits indicate the "+" digit of the second, and the next 4 bits indicate the "-" digit of the second. .

The last 4 bits of time information data T are represented only by BCDI-code.

FIG. 2(B) shows the signal format of one embodiment of the program number data P. In the figure, H is a 9-bit header as in the case of the time information data T in FIG. 2 (Δ). A 16-bit block [12-bit program code in 1 gram number data P] The first 4 bits indicate the "100" digit of the program number, and the next 4 bits indicate the "+" digit of the program number. , the next 4 bits indicate the "-" digit of the program number. The last 4 bits of the program number data P are an extension code that has a special meaning in cases other than BCD codes.

The time information data T and the program number data P each constitute one block consisting of 25 bits together with the header H.
It is transmitted at regular intervals. In this embodiment, this fixed time is set to 1 second.

Therefore, time information data T and program number data P
are transmitted alternately in the middle of the block as shown in FIG. 1(A). FIG. 1(B) shows a numerical example of time information data T and program number data P that are actually transmitted in blocks.

The extension code is, for example, "IA" in hexadecimal notation (i.e. rl
oloJ), the program number data P indicates the program number. Also, for example, in hexadecimal notation "
B" (that is, MOllJ) means that the program number data P indicates a special function. As a result, the time information data T and the program number data P can be identified by
This can be done by detecting the last 4 bits.

In other words, the extension bits are "0" to r9J (roooO
In the case of rAJ (MOloJ), the data is time information data T, in the case of rAJ (MOloJ), it is program number data P, and in the case of rBJ (rlollj), the data is data instructing a special function.

Note that the extension bit is rCJ (rTlooJ') ~
Although we will not specifically explain what the data indicates in the case of rFJ (rllllJ), it goes without saying that various data can be recorded.

In the program number data P, an example of the correspondence between the three codes preceding the extension code and the values of the extension code and the special functions is shown in the following table.

In the table above, Skip is a mode that automatically fast-forwards the recording section from the start point to the end point and does not play it back. For example, after recording a television broadcast signal, skip the commercial broadcast period (8-picture period). Used when you want to skip the replay.

Since the time information data T have continuity with each other within one program, even if the time information data T is missing due to dropout or the like, the missing time information data T can be compensated for by 1 m based on the relationship before and after the time information data T. Furthermore, since the same program number is repeatedly recorded within the same program, even if one program number data P is lost due to dropout, etc.
Can be easily interpolated. However, special function data and the like whose extension code is rBJ do not have continuity, and cannot be interpolated if omissions occur due to dropouts or the like.

Therefore, it is desirable to record data other than time information data such as special function data and evening data and program number data repeatedly two or more times. As a result, even if one piece of data is missing due to dropout or the like, the same data has been repeatedly recorded two or more times, so it is sufficient to use the data that can be reproduced.

The data such as the special function indicated when the value of the above extension code is rBJ to rFJ can be selected and arbitrarily rewritten and recorded by the user of the VTR. It is characterized in that the time information data T is recorded alternately at fixed time intervals, and the time information data T is not rewritten.

FIGS. 3A and 3B show recording patterns of one embodiment of a control track recorded by the apparatus of the present invention.

FIG. 3(A) shows a pattern in which time information data T and program number data P are alternately recorded every second in controls 1 to easy. In addition, FIG. 3(B) shows
This is a pattern in which the extension code of the program number data P in the data shown in FIG. 3 (Δ) is rearranged, resulting in the program number gator P becoming special function data. In addition, in Figures 3 (△) and (B), the shaded area is
It shows.

Next, to explain the recording apparatus of the present invention, FIG. 4 shows an example of an overall configuration diagram of a data recording/reproducing apparatus for a VTR to which the present invention is applied. In the figure, the VTR 11 includes a 1-chip microcomputer 12. Read/write circuit 13. It has a built-in key 11 and a character generator 14, and in addition to the display section 15 similar to a normal VTR, the display panel also has an operation section 16 for data recording and playback and a character output on/off switch 17. The configuration is such that a keyboard 18 is further connected. Further, the VTR 11 is provided with a lid 19 that opens and closes when the tape sets 1 to 1 are inserted and removed, like a normal VTR.

Further, the VTRII outputs the reproduced output video signal and audio signal, and the data to be recorded and reproduced, to the monitor television 21 via the cable 20.

The comment on-screen switch 28 in the data recording/playback operation section 16 is a switch for switching the display on the screen 29 of the monitor television 21, and can be turned on (ON) or off (OF).
The switch that is connected to any one of the three switch positions of F) and SCROLL, and is in the rONJ position, is marked rKEY I NJ at the bottom of the screen 29 of the monitor television 21. The characters are displayed and the characters ``TAPE 0UTJ'' are displayed.

Also, the comment on-screen switch 28 is turned OFF.
When it is in the J position, no characters are displayed, and l”5
When it is in the CROLLJ position, for example, 1
Displays a total of 9 lines of characters with 10 characters per line (
This display mode is hereinafter referred to as [scroll display mode]).

Next, the configuration and operation of the main parts of the VTR 11 will be explained in the fifth section.
This will be explained along with the block system diagram shown in the figure.

In FIG. 5, the same components as those in FIG. 4 are given the same reference numerals. In this embodiment, there are three types of data that can be recorded (for example, there are three types, and the switch SW1 is configured to select only one of them.
When a low level signal is applied to the input ports indicated by rΔDDRESSJ and rlNDEXJ, the recording mode of the special function data, program number data, and index signal is entered. Here, the index signal is a signal in which a certain value is repeated a certain number of times, and is used for relative cue playback.

At the time of recording, the microcomputer 12 determines the data to be recorded based on the signal from the switch SW1, and according to the data to be recorded from the keyboard 18 etc., as shown in FIG. 2 (△).
, generates and outputs data in a predetermined format as shown in (B).

Note that if the microcomputer 12 determines that the signal to be recorded is an index signal, it will immediately input it, or if it determines that the signal to be recorded is program number data, it will input the number from the keyboard 18 or the character key in the operation unit 16. Program number data in data memory (RAM)
If it is determined that the VTR is in the playback mode after the data has been stored, it is determined whether or not the fortune change key 27 has been pressed.

This rewrite key 27 is pressed by the user when the user puts the VTR in playback mode and detects the beginning position of the place where data is to be recorded by monitoring the playback image on the monitor television 21.

When the microcomputer 12 detects that the rewriting key 27 has been pressed, it synchronizes the phase with the reference pulse of the subsequent reproduction control pulses and changes the duty cycle of the control pulses bit by bit according to the format of the recorded data. The reading/writing circuit 13 is made to perform this operation, and this state is continued until the recorded data is completed.

Next, the data recording operation in this reproduction mode will be explained with reference to FIGS. 5 and 6 (A) to (H). The recorded magnetic tape on which data is to be recorded is stored in a tape cassette and loaded into the VTR 11.
During normal playback, the magnetic tape is pulled out from the cassette and passed through a rotating body to which a rotating head is attached four times in the rl direction over a predetermined angular range (loading condition Ea>, capstan The control head 34 shown in FIG. Control system 11
．． It is well known that this signal is used as a quasi-signal or as a comparison signal for a phase control system of a capstan servo circuit to keep the rotational phase of the 4-Yabstan constant.

Here, while the control pulse during recording is a square wave, the playback control pulse is differentiated according to the differential characteristics of the head, and becomes a positive pulse at the rising edge of the recording square wave, and a negative polarity pulse at the falling edge of the recording square wave. is reproduced with a waveform as shown by a in FIG. 6(A), but of this reproduction control pulse a, only the positive polarity pulse is used as a control pulse in each of the servo circuits, and the negative polarity pulse is used as a control pulse in the servo circuit. Not used in

In this case, the recorded magnetic tape is played back and the positive polarity control pulse (hereinafter referred to as "reference pulse") used for the servo circuit is normally supplied to ensure normal servo operation. Because it is necessary to perform recording while changing the duty cycle of the control pulse according to the recording data, re-recording (erasing) is prohibited during the reproduction period of the reference pulse and some period before and after it, and In order to erase the section between adjacent reference pulses and re-record (rewrite) a signal such that the reproduction control pulse has negative polarity, the microcomputer 12 performs the process shown in FIG. 6 (B
) is applied to the switch circuit 33 as a switching pulse, and is turned on only during its high level period.

Also, at the same time, the microcomputer 12
As shown in FIG. 6(C), the signal from the ECCTL 1 to the recording control circuit 31 rises at the rising edge of pulse b, and
Generates and outputs a pulse C that falls when a period corresponding to the value of each pin 1- of data to be recorded has elapsed (however, this period is smaller than the high level period of pulse b), From the output port RECCTL2 to the recording control circuit 31, as shown in FIG.
A pulse d which rises immediately before the falling edge of the pulse b is generated and outputted so that the negative polarity pulse of the pulse d can be erased.

Pulses C and d are supplied to the recording control circuit 31. Drive amplifier 3
2. The signals are supplied to the control head 34 through the switch circuits 33, respectively, and the signals shown in FIG.
) A recording current C as shown in FIG. Recording current e is pulse C
flows in the positive direction during the high level period of pulse d, and falls in the negative direction during the high level period of pulse d, but does not flow during the period when both pulses C and d are at low level and during the low level period of pulse b when the switch circuit 33 is off. .

As a result, the reference pulse of the reproduction control pulse a remains unchanged, the negative polarity pulse is erased by the positive or negative recording current e, and the negative polarity pulse is erased at the time when the recording current e changes from the positive direction to the negative direction. A new record will be created. This operation allows recording of all bits of recording data.
is repeated until When the recorded magnetic tape on which recording has been performed in this manner is subsequently reproduced, the reproduced foot roll pulse waveform becomes as shown by f in FIG. 6(F).

This reproduction control pulse f has a cycle of one frame, and its reference pulse position is the same as the original reproduction position before data recording, but its duty cycle is such that 1 bit of the recorded data is "1". When , the first value (for example, the value where the interval between the positive polarity pulse and the negative polarity pulse is 27.5% of one frame) is obtained, and when one pit of the recorded data is rOJ, the second value (for example, the value where the interval between the above pulses is 27.5% of one frame) is set. is 60% of one frame), and when no data is recorded, the duty cycle of the control pulse is recorded and reproduced so that it is the same as the second value as before.In addition, the program number If the first shift of the data extension code is rBJ to v3 of "F", the data does not have continuity, so the same data value is repeatedly recorded two or more times.

Note that when a low level signal is applied to the input port INDEX by the data select switch SW1, the control pulse is set in advance with a short duty.
It is recorded continuously a certain number of times in a cycle, and this becomes the index signal.

Note that data recording can also be performed in the VTR recording mode. In this case, the pulse width of the recording control pulse, which is a square wave with a period of one frame, for example, is modulated according to recording data and recorded. It should be noted that even in this recording mode, by changing the software of the microcomputer 12, the VTR data can be easily recorded after the rewrite key 27 is pressed.

Next, the cueing operation based on the data written as described above will be explained. It is assumed that cueing is performed in the loading state. When cueing, the microcomputer 12 first detects whether or not the comment on-screen switch 28 is in the rONJ switch position (when the comment on-screen switch 28 is in the rONJ switch position, the switch circuit 28a in FIG. 5 is turned on), When the switch is in the position, it causes the character generator 14 to generate character information related to the data input from the keyboard 18 (or character key), and also outputs character information from the internal memory (RA).
M).

The output signal of this character generator 14 is
The video signal reproduced from the recorded magnetic tape by 11 and input to the input terminal 44 shown in FIG. will be displayed.

Thereafter, the microcomputer 12 puts the VTRII into fast forward or rewind mode while still in the loading state, reads the recorded data from the duty cycle of the control pulses played from the control track during that mode, and stores it in the internal memory. If the value of the extension code of the program number data is rBJ to rFJ, and the value of the extension code of the program number data is rBJ to rFJ, if the values match two or more times, control is performed to set the VTR to playback mode and then enter the desired playback mode. Let's do it.

Here, to explain the readout of recorded data, the timing generator 42 operates at a timing at a duty cycle between the maximum duty cycle and the minimum duty cycle of the reproduction control pulse, as shown in FIG. 6(G). A timing pulse Q is generated that rises and falls at the timing of the reference pulse.

The microcomputer 12 latches the output pulse of the Schmitt trigger circuit 36 at the rising edge of the timing pulse q, thereby generating detection data h as shown in FIG. 6()-1).
After importing the data, format it with hardware or software, read the written data,
Character generator 14. Addition circuit 43. It is output through the output terminal 45 and displayed on the monitor television 21.

Substantially the same operation is performed in the scroll display mode (at this time, the switch circuit 28b in FIG. 5 is on).

Next, the circuit configuration and operation of the reproduction system will be explained with reference to FIG. In the figure, the same components as in FIG. 5 are given the same reference numerals. In FIG. 5, the microcomputer 12 makes a decision as to whether or not the data is being reproduced correctly, but in FIG. 7, this is implemented using hardware. terminal 50
The incoming reproduction control pulse is supplied to the timing generator 42 while being applied to the data input terminal of the D-type flip-flop 51, where the timing generator 42
It is latched at the rising edge of pulse q as shown in FIG. 6(G). As a result, when data f is reproduced, reproduced data h as shown in FIG. be done. The shift clock CK of the shift register 52 is synchronized in phase with the reference pulse from the timing generator 42 as shown in FIG.
A clock as shown in A) is used.

The 9-bit data temporarily stored in the shift register 52 is supplied to comparators 53 and 54. The comparator 53 compares the 9-bit data with comparison data [101111100J, and the comparator 54 compares the 9-bit data with the comparison data [101111100J]. Comparison data
Compare with o01111101J. Comparators 53 and 54 each output a high level signal as shown in FIG. 8(B) when the 9-bit data and the comparison data match. Note that among the 9-bit output data of the shift register 52, L
SB is output from the data output terminal 55.

The output signals of the comparators 53 and 54 are respectively applied to the J and J terminals of the J-type flip-flop 56, and for example, during REW, the output signals from the Q and σ output terminals of the J-K ffl flip-flop 56 are applied to the J-type flip-flop 56, as shown in FIG. FF, RE as shown in (D)
A W signal is obtained and output from terminals 57 and 58. Comparison 6
The output signals of 53 and 54 are also supplied to the OR circuit 59,
The output signal of the R circuit 59 is applied to the data terminal of a D-type flip-flop 60. For example, from the Q output terminal of the D-type flip-flop 60, 5TART as shown in FIG.
A signal is obtained and output from the terminal 61. Note that the clock G is connected to the clock terminals of the flip-flops 56 and 60.
K is applied.

The 25-times counter 62 counts the clock CK and becomes high level when the count value reaches 25 (FIG. 8(F))
Outputs a signal as shown in . The output signal of the counter 62 is supplied three times to the data terminal of the counter 63 and to one input terminal of the NOR circuit 64. The other input terminal of the NOR circuit 64 is supplied with the output signal of the OR circuit. Also, N.

The output signal of R circuit 64 is applied to the reset terminals of counters 62 and 63. As a result, if the header H is not detected and the count of the number 1-1 of the counter 62 is not 25,
The counters 62 and 63 are being reset frequently. The counter 63 outputs a READY signal from the terminal 65 as shown in FIG. 8(G), which becomes high level when the high level signal of the counter 62 is counted three times or more. If only the output No. 2 of the counter 62 or the detection signal of the header 1 is 17, the output signal of the counter 63 is at a low level as shown by the broken line in FIG. 8(G), indicating that the data is not being reproduced correctly. It can be determined that there is no

In this way, in this embodiment, it is determined whether data has been correctly reproduced three or more times, so even if dropouts occur, the effects of dropouts can be greatly reduced and correct data output can be achieved. Obtainable.

Next, the interrupt routine of the microcomputer 12 for processing data such as special function data will be explained with reference to FIG. In the figure, data is fetched in step S1, and it is determined in step S2 whether or not the interrupt is caused by a start signal from the terminal 61.

If the determination result in step S2 is No, the operation returns to the original state, and if it is YES, the process proceeds to step S3. Step S3 takes in the data from the data output terminal 55 in synchronization with the clock CK, and step S4 takes in the data from the data output terminal 55 in synchronization with the clock CK.
It is determined whether or not the interrupt is caused by the DY signal. If the determination result in step S4 is No (7), the operation returns to the original state, and if YES, the process proceeds to step S5. Step S5
performs serial/parallel conversion of the data, and in step S6 it is determined whether or not vl is added by the FF signal from the terminal 57.

If the determination result in step S6 is No, the bit position of the data is inverted (all 16 bits are inverted) in step S7, and then the process proceeds to step S8, but if the determination result is YES, the process directly proceeds to step s8. Step S8 separates the last 4 bits of the data (i.e., the extension code) and determines whether the value is rAJ. If the determination result is YES, step SIO selects the extension code from the data. Separate the preceding 12 bits of program code. Step s11 compares the separated program code with the previously written program code, and step s12 determines whether or not the compared program codes match.

If the determination result in step S12 is NO, step s
At step 13, the data is stored in the memory, and then the operation returns to normal.

On the other hand, if the determination result in step s12 is YES, it is determined that the program code has been correctly reproduced, and the program number is displayed as necessary, and then 9) + production returns to its original state.

By the way, if the determination result in step S9 is No, it is determined in step s15 whether or not the value of the extension code is rBJ. If the determination result in step 315 is YES, it is determined in step s16 whether the code preceding the extension code and the value of the extension code are [001BJ.

If the determination result in step S16 is YES, step s
17 sets the VTR to FF summer mode, and then the operation is restored. On the other hand, if the determination result in step s16 is No, it is determined in step s18 whether the code preceding the extension code and the value of the extension code are "002B". If the determination result in step 818 is No, the operation returns to the original state, and if the determination result is YES, step s
19, the VTR is set to play mode, after which the operation is restored.

If the determination result in step S15 is No, step s2
0 captures data as time information.

In step 921, it is determined again whether the mode is FF mode. If the determination result in step s21 is YES, a predetermined number is added to the previous stored data, and if the determination result is NO, the REW mode is set in step s23. Step s24 subtracts a predetermined number from the previous stored data. Step s25 determines whether the data matches the data obtained by adding or subtracting the stored data. If the determination result in step S25 is No, the operation returns to the original state after storing the data, and if the determination result is YES, step S8
At step 27, it is determined that the time information has been correctly reproduced, the time information is displayed as necessary, and then the operation returns to normal.

In addition, in the explanation of FIG. 9, the value of the extension code is "C" to rF.
A description of the processing in case J has been omitted.

In the above embodiment, 1 second corresponds to 25 bits because the data recording device is CCIR compatible, but the device of the present invention can be applied to NTSC system etc., and in that case, 1 second corresponds to 25 bits. It would be good if it could support 30 bits. Furthermore, the header is not limited to 9 bits.

In the above embodiment, since the time information data is represented by 16 bits, it is possible to represent up to 3 hours, 59 minutes, and 59 seconds. The maximum recording and playback time of a VTR is 8 hours in 3x mode, but when multiple programs are recorded on a magnetic tape, one program is usually within 4 hours, so a maximum of 3 hours, 59 minutes, and 59 seconds can be displayed. It is sufficient.

However, if the header is changed or one second corresponds to 30 bits, it may be changed so that it can represent four hours or more.

Effects of the Invention As described above, according to the present invention, since time information data and program number data are recorded alternately at regular intervals,
The beginning of each program can be detected by detecting the program number, and time information based on the signal recording start position on the magnetic tape or each program recording start position can be obtained from the time information data. Random access is reliably possible from any position on the top, and data such as special functions is recorded by rewriting the program number data, so time information is not erased and can be changed to time information by recording data such as special functions. No disturbance occurs, for example, if the above fixed time is 1
If the time information data and program number data are set to seconds and recorded in blocks with headers added to each, the running direction of the magnetic tape is detected from each header, and the absolute time and absolute position on the tape are recorded. Furthermore, by repeatedly recording data such as special functions two or more times instead of program number data, these data can be reliably reproduced even if a drop-ac etc. occurs. It is something.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an example of the recording pattern of a control track recorded by the device of the present invention, and FIG. 2 is a diagram showing an example of the A-mat of data recorded by the device of the present invention. FIG. 3 is a diagram for explaining recording patterns before and after data such as special functions are recorded, and FIG. 4 is an overall configuration diagram of an example of a recording and reproducing apparatus to which the present invention can be applied.
5 is a block system diagram of the main parts in FIG. 4, FIG. 6 is a signal waveform diagram for explaining the operation of the block system shown in FIG. 5, and FIG. 7 is a main part of the reproduction system of the apparatus shown in FIG. FIG. 8 is a signal waveform diagram for explaining the operation of the circuit system shown in FIG. 7, and FIG. 9 is a circuit system diagram without showing an example. FIG. It is a flowchart which shows an example of operation. H...Header, T"...Time information data, P...
Program number data, 11...VTR, 12...
1 chip microcomputer, 13...
・Read/write circuit, 14...Character generator,
16... Data recording/reproducing operation unit, 18... Keyboard, 21... Monitor TV, 34... Control head, 52... Shift register, 53.54...
-Comparator, 62.63...Counter. Patent applicant: Mino□ to Victor Japan Co., Ltd. Figure 4

Claims (3)

[Claims] (1) Data such as positional information and special functions of the magnetic tape on which video signals are recorded and played back by the VTR are selected as appropriate, and the duty cycle of control pulses of a fixed period is varied according to the value of the selected data. A VTR data recording device that records on a control track of a tape, which includes time information data and a program number indicating the program number of the program based on the signal recording start position on the magnetic tape or the recording start position of each program of the video signal. 1. A data recording device for a VTR, characterized in that it is configured to record data alternately at regular intervals. (2) Data recording of a VTR according to claim 1, wherein the time information data and the program number data are alternately recorded every second in block units to which headers are added. Device. (3) The VTR according to claim 1, wherein the data such as the special function is the same data that is repeatedly recorded two or more times instead of the program number data.
data recording device.