JPH0628430B2 - Control data processing method for recording / reproducing apparatus - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control data processing method for a recording / reproducing apparatus, and particularly when control data for controlling operations such as timer recording of an apparatus for recording / reproducing a composite video signal is invalid. Regarding the processing method when it is determined.

Conventional technology Helical scanning type magnetic recording / reproducing apparatus (VT
Control data for controlling operations such as R) timer recording are
The VPS (Video Programming System), which is transmitted by being superimposed on a specific period within the vertical blanking period of the television signal, is transmitted.
The multiplex television system called em) has recently been realized in West Germany. This VPS data is a bi-phase modulation signal in which one word is 8 bits and consists of 15 words in total, and these 15 words are transmitted while being superimposed on one horizontal scanning time of the scanning line number 16 of the PAL system color video signal. The transmission rate of the bi-phase modulation signal (VPS data) is 2.5 Mbit / sec, and there is always a level change in the middle of the bit cycle. When the level change is from high level to low level, it is a logical "1", from low level. When it is at a high level, it indicates data of logic "0".

The first word of VPS data is a sequence of logic "1" (lock component itself), which is 8 bits called a run-in for facilitating clock recovery, and the next second word is called a start code. , Used for determining whether the combined signal is valid and for bit positioning. The first 4 bits of the fifth word indicate the type of audio or video, and the latter 4 bits are not used for spare data. VTR mentioned above
The control data is placed in the 11th to 14th words, and consists of the program broadcast date, time, station name code, country code, and the like. The latter 4 bits of the third, fourth, sixth to tenth words and the fifth word are irrelevant to the control of the VTR or are unused words. The timer recording of the PAL system color video signal by the VTR can be automatically performed by combining the VPS data.

Problems to be Solved by the Invention However, in the case where the VTR is in a certain operation mode and reception of the television broadcast radio wave becomes impossible for a short time due to, for example, passage of an airplane, the VTR
However, there is a problem in that the VTR may not be able to receive the above while the VTR is operating in the recording mode and the VPS data may not come in, so that the VTR may enter the stop mode.

Therefore, the present invention, when the control data is temporarily unreadable, by setting the normal recording start time set by timer recording without being based on the control data,
It is an object of the present invention to provide a control data processing method for a recording / reproducing apparatus which solves the above problems.

Means for Solving the Problems The control data processing method of the recording / reproducing apparatus according to the present invention is appropriate by determining whether or not the control data superimposed in the blanking period of the composite video signal is appropriate. In a control data processing method for changing and controlling a timer recording operation of the recording / reproducing apparatus based on the control data, the determination is continued after the control data is determined to be valid, and a normal recording start time elapses. If it is determined that the control data is not valid before, the control data that is not valid is ignored, and if the normal recording start time has elapsed and the control data is determined to be invalid, normal timer recording is performed. This is a control data processing method for a recording / reproducing apparatus, which is characterized in that the processing shifts.

The broadcast date and time, the broadcasting station, etc. of the composite video signal to be recorded / reproduced by the recording / reproducing apparatus are shown, and the control data for controlling the timer recording of the recording / reproducing apparatus is periodically supplied to the recording / reproducing apparatus. However, even if the control data is no longer supplied to the recording / reproducing apparatus for some reason, the recording / reproducing apparatus can know the start time of the program.

Example FIG. Shows a flowchart of an example of the method of the present invention. The microcomputer that performs the operation shown in the flowchart is a microcomputer that controls the operation of the VTR, and performs the VPS data input processing shown in the figure by interrupt processing. In the figure, the microcomputer judges whether or not the VPS data is in a state of waiting for input (step 1), and when it is in a state of waiting for input, temporarily stores the VPS data. 12
The gate on the input side of the 8-bit 2-system shift register is closed to stop the shift operation of the shift register, the clock is switched, and the error flag is cleared (step 2). Next, the microcomputer uses the above two systems of shift registers (one for each bit cycle (for example, 400 μs)).
The first half of the logical value is stored, and the other half of the latter logical value is stored. The data stored in () are alternately read to check each bit (step 3). That is, the input VPS data is a bi-phase modulation signal, and the logical value (level) is always different between the first half and the latter half of the cycle of each bit. Therefore, when the first half and the latter half of the bit cycle have the same level, the bit is erroneous. And the error flag is set (step 9 described later).

On the other hand, for the correct bit data as a result of the bit check, the microcomputer proceeds to step 4 and checks the start code of the second word of the VPS data, which is randomized in the microcomputer.
It is transferred to the access memory (RAM) and stored.
Next, the microcomputer counts 16, ie, skips the next 16-bit data (third and fourth words), then checks the fifth word, and
The first 4 bits are stored in the RAM, and the next 4
4 bits of data (the last 4 bits of the 5th word and the 6th to 10th words) are skipped (steps 5, 6).
7). The reason for skipping is that the data is not used for controlling the VTR as described above and does not need to be stored.

Next, the microcomputer checks the control data from the 11th word to the 14th word and writes the control data in the RAM (step 8). If the data checked in steps 4, 6 and 8 is incorrect, an error flag is set (step 9). After the processing of step 8 or 9 is completed, the above 2
The gate circuit on the input side of the shift register of the system is set to the gate "open" state, the clock is switched, and the next VPS data can be temporarily stored (step 10). After that, the microcomputer judges the presence or absence of the error flag (step 11),
When there is no error flag, the address is set in the next write area, and the number of times is counted, and when the next write area is, for example, the fourth write area, a carry is output to initialize the address (step 12, 13). On the other hand, when the number of addresses set in the write area in step 12 is less than 3, the microcomputer returns to the main routine processing (step 14).

After the initialization of the address, after setting the set data flag indicating that the control data of each frame transmitted over a total of three frames in the three writing areas are stored, the microcomputer executes the action of the main routine. (Steps 15 and 16).

On the other hand, when an error flag is detected in step 11, the microcomputer counts down the number of the error flag with an error counter (step 1
7), the number of the error flags is a predetermined value (for example, 256).
(Step 18), and if less than a predetermined value, return to the main routine (step 1).
9) When it reaches a predetermined value, the error counter is preset to the predetermined value in preparation for the next processing (step 2).
0). When the processing of step 20- is completed, it is next determined whether or not the reservation start time has passed (step 2
1) If it has not passed, return to the original step 1 and repeat the same operation as above. If it has passed, the microcomputer shifts to normal timer recording regardless of the immediately preceding control data, and then the main routine. (Steps 22 and 23). Here, the normal timer recording is timer recording that is not based on VPS data, and when the start or end time set by the user comes,
Timer recording ends regardless of data. That is,
When the recording start time of timer recording has passed and the number of VPS data reconstruction errors has exceeded a predetermined value (when the normal recording start time has passed and it is determined that the control data is invalid), the recording start time is set to The normal recording start time set at the time of timer recording can be set without being based on the control data. On the other hand, when the number of VPS data decoding errors is less than the predetermined value (when it is determined that the control data is valid), the VTR continues timer recording based on the VPS data and sets the reserved start time. When the time of the VPS data coincides with the time of the VPS data, timer recording is started. If the start time of the broadcast program is suddenly delayed (for example, if the broadcast start of the program following the baseball broadcast is delayed, the VPS data (control data ) Is sent, so VPS
If the number of data decoding errors is less than the specified value, VPS
Timer recording can be performed based on the data to record a desired broadcast program.

In this embodiment, steps 17-19 allow the VTR to continue in its previous operating mode even if no VPS data has arrived for about 10 seconds.

The present invention is not limited to VPS data, but other equivalent VT
It can also be applied to operation control data of a recording / reproducing apparatus such as R. Further, in the above-mentioned embodiment, even if VPS data does not come in, the fixed period for continuing the same operation mode is set to about 10 seconds, but it may be set to any one of 1 second to 10 minutes.

As described above, according to the present invention, when it is determined that the control data superimposed during the blanking period of the composite video signal is invalid, for example, when the control data during the blanking period of the composite video signal is Even if it is transmitted without being superimposed or if the control data cannot be combined for a certain period of time, it is possible to reliably record from the beginning of the program without missing a part of the program you want to record, and it is possible to prevent malfunctions. Is to have.

[Brief description of drawings]

 The figure is a flow chart showing an embodiment of the present invention. 1 to 23 ... Step.

Claims (1)

[Claims] 1. A recording / reproducing apparatus determines whether or not the control data superimposed during a blanking period of a composite video signal to be recorded / reproduced is appropriate, and the recording is performed based on the control data being valid. In the control data processing method for changing and controlling the timer recording operation of the reproducing apparatus, the judgment is continued after it is judged that the control data is valid, and the control data is not valid before the normal recording start time has elapsed. If the control data is determined to be invalid, the control data that is not valid is ignored, and if the normal recording start time has elapsed and if the control data is determined to be invalid, the normal timer recording is performed. Control data processing method for playback device.