JP4525667B2 - Content storage device - Google Patents

Description

  The present invention relates to a content storage device, and more particularly to a content storage device that performs time synchronization.

  Patent Document 1 discloses an electronic timepiece including an antenna, a tuner, an oscillator, a rate adjustment circuit, a frequency divider, a CPU (Central Processing Unit), a storage device, and an LCD (Liquid Crystal Display). . The antenna receives broadcast radio waves. The tuner extracts a predetermined synchronization signal from the broadcast radio wave received by the antenna. The oscillator oscillates a clock signal having a predetermined frequency. The rate adjustment circuit adjusts the frequency of the clock signal. The frequency divider divides the clock signal output from the oscillator to generate a clock signal for timing. The storage device stores the number of clocks to be output by the oscillator during a period from when a tuner extracts a certain synchronization signal to when the next synchronization signal is extracted. The CPU measures the time based on the clock for clocking, detects the number of clock signals output from the oscillator during the above-described period, and compares the number of clock signals with the number of clock signals stored in the storage device to determine an error. calculate. The LCD outputs in a state where the error can be recognized.

According to the invention disclosed in Patent Document 1, an electronic timepiece can always be accurate by using a synchronization signal included in a broadcast radio wave.
Japanese Patent Laid-Open No. 5-87956

  However, the invention disclosed in Patent Document 1 has a problem that wasteful power may be consumed to obtain an accurate time. This is because there is no way for the electronic timepiece to know whether or not the time being measured is correct, and therefore a synchronization signal must be extracted from the broadcast radio wave regardless of whether or not the time being measured is correct.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a content storage device capable of suppressing consumption of unnecessary power for adjusting the time.

  In order to achieve the above object, according to an aspect of the present invention, a content storage device includes a generation unit, a signal input unit for inputting a broadcast signal, an extraction unit, a data recording unit, and an oscillation unit. , Including control means and display means. The generation means generates a control signal according to the operation. The extraction means extracts the synchronization signal from the broadcast signal. The data recording means records content data represented by the broadcast signal. The oscillating means oscillates a clock signal. The control means controls the data recording means. The display means displays the time calculated by the time calculation means. The control means includes a correction value calculation means, a time calculation means, and a means for controlling the data recording means according to information represented by the control signal. The correction value calculation means calculates a value corresponding to the number of clock signals oscillated by the oscillation means as the correction value while the extraction means extracts the synchronization signal. When the correction value calculation means calculates the correction value in the period from the time when the data recording means starts the operation to the time after the operation stops, the time calculation means corrects the clock signal corrected based on the correction value. The time is calculated based on the number.

  According to another aspect of the present invention, the content storage device includes a generation unit, a signal input unit for inputting a broadcast signal, an extraction unit, a data recording unit, an oscillation unit, a control unit, and a display unit. including. The generation means generates a control signal according to the operation. The extraction means extracts the synchronization signal from the broadcast signal. The data recording means records content data represented by the broadcast signal. The oscillating means oscillates a clock signal. The control means controls the data recording means. The display means displays the time calculated by the time calculation means. The control means includes correction value calculation means, time calculation means, and means for controlling the data recording means in accordance with information represented by the control signal. The correction value calculation means calculates a value corresponding to the number of clock signals oscillated by the oscillation means as the correction value while the extraction means extracts the synchronization signal. The time calculation means calculates the time based on the number of clock signals corrected based on the correction value when the correction value calculation means calculates the correction value.

  Further, the time calculation means described above is the number of clock signals corrected based on the correction value when the requirement that the surface temperature of the oscillation means is higher than the threshold is satisfied and the correction value calculation means calculates the correction value. Based on this, it is desirable to include means for calculating the time.

  Further, the time calculation means described above is corrected based on the correction value when the correction value calculation means calculates the correction value during the period from the time when the data recording means starts the operation to the time after the operation is stopped. It is desirable to include means for calculating the time based on the number of clock signals.

  Further, the time calculation means described above is for calculating the time based on the number of clock signals corrected based on the correction value when the correction value calculation means calculates the correction value in a time zone including noon. It is desirable to include means.

  In addition, the content storage device described above preferably further includes a detection unit for detecting the temperature. In addition, the time calculation means calculates the time based on the number of clock signals corrected based on the correction value when the temperature is equal to or higher than the threshold and the correction value calculation means calculates the correction value. It is desirable to include means.

  The content storage device according to the present invention can suppress useless power consumption for adjusting the time.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed description thereof will not be repeated.

  The hard disk recorder 10 in FIG. 1 is a content storage device that records various types of content on two types of recording media. The hard disk recorder 10 is also a device that outputs various contents reproduced from a recording medium so that the content can be viewed as a video signal or an audio signal on a monitor device 14 connected in advance to the outside of the device. The remote controller (abbreviated as a remote controller) 12 is a device operated by a user to input various commands, and transmits an infrared signal corresponding to the commands.

  The hard disk recorder 10 includes a DVD (Digital Versatile Disc) drive 20, an HD (Hard Disk) device 22, an analog tuner 24 connected to an external terminal 44 described later, and an MPEG (OSD (On Screen Display) 50 built-in. Motion Picture Experts Group) codec engine 26, memory 28, video output unit 30, audio output unit 32, remote control reception unit 34, microcomputer (abbreviation of microcomputer) 36, crystal 37 (usually “crystal” (Referred to as “crystal” in the present embodiment), an external I / F (Inter Face) 38 for connecting an external device 70 for supplying digital information from the outside, and time and other information. LCD 40 to display, temperature sensor 42 connected to microcomputer 36, and digital broadcast signal transmitted from broadcast station Connect the external antenna 60 that includes an external terminal 44 for receiving an input of the digital broadcast signal.

  The DVD drive 20 is a device that reads video data and audio data of digital contents recorded as signals on an optical disc (DVD disc 300 in the present embodiment). In the present embodiment, video data and audio data recorded on an optical disk or other recording medium are referred to as “content data”. The DVD drive 20 is also a device for recording content data signals on an optical disk.

  The HD device 22 is a device that records a content data signal of digital content desired by a user on the hard disk 52 and reads the recorded content data signal of the digital content. Here, examples of the content data recorded on the hard disk 52 include video files conforming to the MPEG2 standard and audio files conforming to the MP3 (MPEG-1 Audio Layer3) standard. The HD device 22 stores an operation program for the microcomputer 36.

  The HD device 22 reads data recorded as signals on a recording medium (hard disk 52 in the case of the present embodiment) and information indicating chapters (digital content boundaries), and records them on the recording medium. Recording head 56.

  The analog tuner 24 is a device that extracts and outputs a broadcast signal (digital content signal) of a channel designated by the microcomputer 36 when the antenna 60 receives a broadcast signal of digital content transmitted from a broadcasting station. One type of broadcast signal to be extracted includes a horizontal synchronization signal and a vertical synchronization signal. As a result, the analog tuner 24 selects one of the broadcast signals received by the antenna 60.

  The MPEG codec engine 26 includes a content data signal reproduced by the DVD drive 20, a content data signal read from the hard disk 52, and a digital content signal input from the external device 70 via the external I / F 38. When any of these is given by the switching control of the microcomputer 36, the digital signal is received, decoded (decoded), and output. The MPEG codec engine 26 compresses the content broadcast signal extracted by the analog tuner 24 as a content data signal under the control of the microcomputer 36 in order to record the digital content signal in the DVD drive 20 or the HD device 22. It is also a device that compresses a digital signal input via the external I / F 38. The OSD 50 built in the MPEG codec engine 26 creates image data based on information given by the microcomputer 36 and outputs it to the video output unit 30 for visual display on the screen of the monitor device 14.

  In the memory 28, broadcast channels that can be received by the analog tuner 24 are acquired and stored in advance by channel scanning (auto scanning). The memory 28 also stores information representing time.

  The video output unit 30 is a device that outputs video data read by the read head 54 from the hard disk 52 and decoded by the MPEG codec engine 26 as a signal. The video output unit 30 converts the video data into a video signal that can be output by the monitor device 14, and then outputs the video signal to the monitor device 14. The video output unit 30 is also a device that outputs information created by the OSD 50 as a video signal.

  The audio output unit 32 is an apparatus that outputs audio data read by the read head 54 from the hard disk 52 and decoded by the MPEG codec engine 26 as a signal. The audio output unit 32 converts the audio data into an audio signal that can be output by the monitor device 14, and then outputs the audio signal to the monitor device 14.

  The remote control receiving unit 34 is a device that receives various command signals transmitted from the remote control 12 via infrared rays. The remote control receiving unit 34 generates a control signal corresponding to a user operation on the remote control 12 and transmits the control signal to the microcomputer 36.

  The microcomputer 36 is a device that controls each part of the device based on an operation program stored in the memory 28.

  The crystal 37 generates a clock signal. In the present embodiment, the “clock signal” means a signal used for adjusting the operation timing of the microcomputer 36. In the present embodiment, recording on the recording medium to the optical disk or the like is not performed, and in the case of nighttime, the period of the clock signal is equal to the period in which the analog tuner 24 extracts the horizontal synchronization signal.

  The temperature sensor 42 detects the temperature around the crystal 37. The sensor attached as the temperature sensor 42 is not particularly limited, but in the present embodiment, a thermistor is attached.

  FIG. 2 is a diagram showing the configuration and functions of a part of the microcomputer 36 that is involved in time calculation. Referring to FIG. 2, microcomputer 36 includes a tuner counter 80, a crystal counter 82, and a CPU 84.

  The tuner counter 80 counts the synchronization signal extracted by the analog tuner 24. In the present embodiment, the synchronization signal counted by the tuner counter 80 is a horizontal synchronization signal. Each time the tuner counter 80 counts the horizontal synchronization signal, it outputs the number of horizontal synchronization signals counted so far to the comparator 92 described later.

  The crystal counter 82 counts the clock signal output from the crystal 37. Each time the crystal counter 82 counts the clock signal, it outputs the number of clock signals counted so far to the comparator 92 and the calculator 94 described later.

  The CPU 84 calculates numerical values and outputs control signals to the video output unit 30 and the audio output unit 32.

  The CPU 84 operates as the comparison unit 92, the calculation unit 94, or the control unit 96. In the case of the present embodiment, the comparison unit 92, the calculation unit 94, or the control unit 96 can be regarded as a virtual circuit realized by the CPU 84.

  The comparison unit 92 calculates a value obtained by subtracting the number of clock signals output from the crystal counter 82 from the number of horizontal synchronization signals output from the tuner counter 80. The comparison unit 92 outputs the value as a correction value to the calculation unit 94.

  The calculation unit 94 performs a calculation that is not handled by the comparison unit 92. The calculation performed by the calculation unit 94 includes a calculation for calculating time. In the case of the present embodiment, the arithmetic unit 94 calculates time according to the following procedure. The first procedure is a procedure for subtracting the correction value output from the comparison unit 92 from the number of clock signals output from the crystal counter 82. However, when the comparison unit 92 does not output the correction value, the first procedure is not performed. The second procedure is a procedure for multiplying the value obtained as a result of the subtraction in the first procedure by a coefficient. When the first procedure is not performed, the number of clock signals output from the crystal counter 82 is multiplied by a coefficient. As a result, the number of clock signals output from the crystal counter 82 is converted into an elapsed time from when the crystal counter 82 starts outputting the number. The third procedure is a procedure of adding the time when the number of clock signals output from the crystal counter 82 is “0” to the value obtained as a result of the multiplication in the second procedure.

  The control unit 96 controls each unit of the hard disk recorder 10 by executing a program copied from the hard disk 52 to the memory 28. With this control, the DVD drive 20 and the HD device 22 record digital contents, and the LCD 40 displays the time.

The operation of the hard disk recorder 10 based on the above structure will be described.
[When correcting the number of clock signals during recording on a DVD disc]
When the user operates the remote controller 12 to start recording, the remote controller receiver 34 receives a signal from the remote controller 12. When the signal is received, the remote control receiving unit 34 generates a control signal corresponding to the signal.

  When the control signal is generated, the control unit 96 controls the DVD drive 20 and the analog tuner 24 so that the video data and audio data received as the broadcast signal by the antenna 60 are recorded on the DVD disk 300.

  At the same time, the control unit 96 outputs a signal to the comparison unit 92. When the signal is output, the comparison unit 92 starts calculating a value obtained by subtracting the number of clock signals oscillated by the crystal counter 82 from the number of horizontal synchronization signals output by the tuner counter 80.

  The calculation unit 94 calculates time using the number of clock signals corrected based on the value calculated by the comparison unit 92.

  When the time is calculated, calculation unit 94 outputs information representing the time to LCD 40. The LCD 40 displays the time based on the information.

  Thereafter, when the user operates the remote controller 12 to finish the recording, the remote controller receiver 34 receives a signal from the remote controller 12. When the signal is received, the remote control receiving unit 34 generates a control signal corresponding to the signal.

  When the control signal is generated, the control unit 96 controls the DVD drive 20, the analog tuner 24, and the like so as to finish the recording of the video data and the audio data.

  After the DVD drive 20 and the analog tuner 24 are controlled, the calculation unit 94 continues to calculate the time. The calculated time information is output not only to the LCD 40 but also to the control unit 96. Based on the time, the control unit 96 determines whether or not a predetermined period has elapsed after the DVD drive 20 stops operating.

  The “predetermined period” here is a period corresponding to the heat generation amount and the cooling rate of the DVD drive 20. When this period elapses, the DVD drive 20 is sufficiently cooled, so that the heat from the DVD drive 20 does not adversely affect the frequency of the clock signal.

  When the predetermined period has elapsed, the control unit 96 controls the comparison unit 92 to stop calculating the correction value.

[When correcting the number of clock signals during the day]
The calculation unit 94 calculates time. In this case, if the comparison unit 92 has not calculated a correction value, the correction of the time is not performed.

  When the time is calculated, information representing the time is output to the control unit 96. The control unit 96 determines whether or not the time is included in a certain time zone including noon. In the case of the present embodiment, this time zone is predetermined.

  When the time calculated by the calculation unit 94 is included in the time zone, the control unit 96 outputs a signal to the comparison unit 92. When the signal is output, the comparison unit 92 starts calculating a value obtained by subtracting the number of clock signals oscillated by the crystal counter 82 from the number of horizontal synchronization signals output by the tuner counter 80.

  The calculation unit 94 calculates the time using the number of clock signals corrected based on the value that the comparison unit 92 started calculating earlier.

  When the time is calculated, calculation unit 94 outputs information representing the time to LCD 40. The LCD 40 displays the time based on the information.

  When the time is calculated, information representing the time is output to the control unit 96. The control unit 96 determines again whether or not the time is included in a certain time zone including noon.

  Initially, the time is included in the time zone. However, thereafter, the time is not included in the time zone. When the time is no longer included in the time zone, the control unit 96 controls the comparison unit 92 to stop calculating the correction value.

[When correcting the number of clock signals according to the temperature sensor output signal]
The temperature sensor 42 periodically outputs information representing the temperature to the control unit 96. When the information is output, the controller 96 determines whether the temperature is equal to or higher than a threshold value.

  When the temperature is equal to or higher than the threshold, the control unit 96 outputs a signal having content corresponding to the temperature being equal to or higher than the threshold to the comparison unit 92. When the signal is output, the comparison unit 92 starts calculating a value obtained by subtracting the number of clock signals oscillated by the crystal counter 82 from the number of horizontal synchronization signals output by the tuner counter 80.

  The calculation unit 94 calculates the time using the number of clock signals corrected based on the value that the comparison unit 92 started calculating earlier.

  When the time is calculated, calculation unit 94 outputs information representing the time to LCD 40. The LCD 40 displays the time based on the information.

  Thereafter, when the temperature detected by the temperature sensor 42 becomes less than the threshold value, the control unit 96 controls the comparison unit 92 to stop calculating the correction value.

  As described above, the hard disk recorder 10 according to the present embodiment updates the correction value based on the number of horizontal synchronization signals from the start of recording until a predetermined period elapses after the end of recording. Further, the hard disk recorder 10 corrects the time using the updated correction value. As a result, it is possible to suppress time deviation without requiring a tuner for a radio timepiece. Since the time adjustment uses the analog tuner 24 that operates for recording, the power consumed for the time correction is negligible. In addition, the period during which the DVD drive 20 is operating for recording is a period during which the crystal 37 is easily affected by the heat generated from the DVD drive 20, so even if the time is corrected during this period, The error is much smaller. As a result, it is possible to provide a recorder capable of accurately correcting the time with very little power without causing an increase in production cost. Moreover, since the time is accurately corrected, the possibility of failing to record the program reserved by the user can be greatly suppressed.

  Further, the hard disk recorder 10 according to the present embodiment updates the correction value based on the number of horizontal synchronization signals in a time zone including noon. Since the time zone including noon is daytime, an error in the frequency of the clock signal is likely to occur compared to nighttime. By correcting the clock signal output in this time zone, it is possible to suppress time lag.

  Also, the hard disk recorder 10 according to the present embodiment updates the correction value based on the number of horizontal synchronization signals when the detected temperature is equal to or higher than the threshold value. As a result, the clock signal is corrected when the frequency of the clock signal may actually be affected by heat. Thereby, it is possible to accurately suppress time deviation.

  As a first modification, in addition to the case described above, when the requirement that the surface temperature of the crystal 37 is higher than the threshold is satisfied, the calculation unit 94 calculates a correction value based on the number of horizontal synchronization signals. It may be updated. Examples of such requirements other than the period from the start of recording to the lapse of a predetermined period after the end of recording and the time zone including noon include a case where the continuous operation time of the hard disk recorder 10 exceeds a threshold. is there.

  In addition, as a second modification, the temperature sensor 42 may not be included when the correction time of the number of clock signals is determined based on a time zone, recording, or the like.

  As a third modification, the operations of the comparison unit 92, the calculation unit 94, and the control unit 96 may be performed by a dedicated IC (Integrated Circuit). These operations may be performed by a single IC or a plurality of ICs.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

It is a figure showing the structure of the hard-disk recorder concerning embodiment of this invention. It is a figure showing the structure of the microcomputer etc. concerning embodiment of this invention.

Explanation of symbols

  10 hard disk recorder, 12 remote control, 14 monitor device, 20 DVD drive, 22 HD device, 24 analog tuner, 26 MPEG codec engine, 28 memory, 30 video output unit, 32 audio output unit, 34 remote control reception unit, 36 microcomputer, 37 Crystal, 38 External I / F, 40 LCD, 42 Temperature sensor, 44 External terminal, 50 OSD, 52 Hard disk, 54 Read head, 56 Recording head, 60 Antenna, 70 External device, 80 Tuner counter, 82 Crystal counter, 84 CPU , 92 comparison unit, 94 calculation unit, 96 control unit, 300 DVD disc.

Claims (4)

Generating means for generating a control signal in response to an operation;
A signal input means for inputting a broadcast signal;
Extraction means for extracting a synchronization signal from the broadcast signal;
Data recording means for recording content data represented by the broadcast signal;
An oscillation means for oscillating a clock signal;
A correction value calculation means for calculating a value obtained by subtracting the number of the clock signals from the number of the synchronization signals based on the extraction of the synchronization signal;
Time calculation means for subtracting the correction value from the number of the clock signals based on the calculation of the correction value, and calculating a time based on the clock signal after the subtraction;
Means for controlling the data recording means in accordance with information represented by the control signal;
Display means for displaying the time calculated by the time calculation means,
The correction value calculation means calculates the correction value in a period during which the content data is recorded and a predetermined period after the recording ends, and after the predetermined period has elapsed, Content storage device that stops calculation .   The content storage device according to claim 1, wherein the correction value calculation unit calculates the correction value even when a requirement that the surface temperature of the oscillation unit is higher than a threshold is satisfied.   The content storage device according to claim 1, wherein the correction value calculation unit calculates the correction value even in a time zone including noon. The content storage device further includes a temperature sensor that detects an ambient temperature of the oscillation means,
The content storage device according to claim 1, wherein the correction value calculation unit calculates the correction value even when the ambient temperature is higher than a threshold value.

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