JP4297730B2 - Digital broadcast receiver - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a receiver for receiving a digital broadcast, and more particularly to a digital broadcast receiver configured to be able to download an upgrade program or the like carried on a broadcast wave.
[0002]
[Prior art]
For example, in a digital broadcast receiving system using a satellite, a video / audio signal is compressed using a digital signal compression technique, and a stream (transport stream) in which video / audio digital signals of a plurality of programs are time-division multiplexed is used as a transponder. Broadcasts via (satellite repeater). On the other hand, a broadcast receiving apparatus for receiving such a digital broadcast selects one of a plurality of digital broadcast transponders received through a dedicated antenna by a tuner, and among the plurality of channels included in the one transponder. One is selected by demultiplex processing, and a video / audio signal is output by decoding the digital signal of the selected channel.
[0003]
In such digital television broadcasting, new software and download data of common data (such as a company logo and a genre code) are transmitted on a broadcast wave and transmitted in order to fix bugs and improve functions of the software of the receiving device. When the power is turned on, the receiving device transmits download transmission information (corresponding model information (model_id), version of downloaded download data (version_id), transmission schedule, etc. (SDTT: Software Download Trigger Table). It receives and determines whether the download data is valid, and determines whether to perform the download process based on the setting conditions of the receiving device. The setting condition of the receiving apparatus is the user's intention to execute the download, and the download process is not performed under the user setting that the download is not performed. On the other hand, the receiving device that has determined to execute the download receives the download data transmitted at the set date and time within the transmission schedule, for example, writes it in a non-volatile memory such as a flash memory, and at the next startup, etc. Software and common data are upgraded by using the written data (see Patent Document 1).
[0004]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 2002-290869
[Problems to be solved by the invention]
Conventional download data such as software rewrites all data recorded in the nonvolatile memory, and therefore, for example, data of 3 Mbytes or more may be transferred. However, unless significant software modification is performed, the change point of software and the like is expected to be about several bytes to several Kbytes, and sending all software data up to such a case is a waste of transmission bandwidth, In addition, the same data is written to the nonvolatile memory over and over, which shortens the lifetime of the nonvolatile memory.
[0006]
In view of the above circumstances, an object of the present invention is to provide a digital broadcast receiving apparatus capable of efficiently correcting only data changes.
[0007]
[Means for Solving the Problems]
In order to solve the above-described problems, a digital broadcast receiving apparatus according to the present invention is a digital broadcast receiving apparatus configured to receive a digital broadcast wave, demodulate it, and download data. A rewritable nonvolatile semiconductor memory in which data is rewritten, and the downloaded data to be written based on start address information in the header when the downloaded data has a header for each unit data constituting a part of software Means for determining a write start address of the non-volatile semiconductor memory; and means for writing the unit data to the non-volatile semiconductor memory from the determined write start address . the unit same as to Rukoto the size of the data that constitutes a part of a size and software And butterflies.
[0008]
With the above configuration, for example, a part of the software is rewritten instead of rewriting the entire software, so that it is possible to avoid the same data being repeatedly written to the recording medium. Furthermore, the capacity of the memory that temporarily caches download data can also be reduced. Further, in the transmission for downloading, it is possible to avoid waste of the transmission band.
[0009]
There may be provided means for determining unit data for the own device based on the corresponding version information in the header.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to FIG. 1 and FIG. 2, but here, a case where a user views a BS (Broadcasting Satellite) digital broadcast is illustrated.
[0011]
The antenna 1 is arranged outdoors in a predetermined direction and receives a digital broadcast signal sent from the BS. The antenna 1 generally includes a frequency converter, and supplies a received / frequency converted signal to the tuner 2.
[0012]
The tuner 2 extracts a signal having a specific frequency from the received high frequency digital modulation signal. That is, a process of selecting one from a plurality of transponders of digital broadcasting is performed. Further, the tuner 2 includes a demodulation circuit, a deinterleave circuit, an error correction circuit, and the like, thereby demodulating the selected digital modulation signal and outputting a transport stream.
[0013]
Demultiplexer (DEMUX) 3 the transport stream received from the tuner 2, separated into a video stream, an audio stream, PSI / SI (Program Specific Information / Service Information) and download programs of MPEG2 (Moving Picture Experts Group2) To do. The demultiplexer 3 supplies the video stream and the audio stream to the AV decoder 4 and supplies the PSI / SI, the download program, and the like to the CPU 13. As described above, a plurality of channels are multiplexed in the transport stream, and processing for selecting an arbitrary channel from among these is performed in the transport stream from the PSI / SI. Thus, it becomes possible by taking out data such as which packet ID is multiplexed. Also, the download program itself and the ID for extracting it can be extracted from the PSI / SI. Further, selection of a transport stream (selection of a transponder) can be performed based on PSI / SI information.
[0014]
The AV decoder 4 includes a video decoder that decodes a video stream and an audio decoder that decodes an audio stream. The video decoder decodes the input variable length code to obtain a quantization coefficient and a motion vector, and performs inverse DCT conversion, motion compensation control based on the motion vector, and the like. The audio decoder decodes the input encoded signal to generate audio data. The video data generated by the decoding is output to the video processing circuit 5, and the audio data is output to the audio processing circuit 6.
[0015]
The video processing circuit 5 receives the video data from the AV decoder 4, performs D / A conversion, and converts it into, for example, a composite signal in the NTSC format. The audio signal processing circuit 6 receives the audio data output from the AV decoder 4, performs D / A conversion, and generates a right (R) sound analog signal and a left (L) sound analog signal. The video output circuit 7 and the audio output circuit 8 include an output resistor, an amplifier, and the like. The AV output terminal 9 is provided with an output unit (a set of left and right audio output terminals and a video output terminal), and a monitor (not shown) is connected to the output unit.
[0016]
The OSD (On Screen Display) display circuit 12 outputs to the adder 20 a video signal based on character information and graphic information instructed to be output from the CPU 13. The adder 20 incorporates the video signal into the received video signal. The OSD display circuit 12 realizes display of an operation guide screen and the like in addition to the electronic program guide (EPG: (Electronic Program Guide)) based on the aforementioned PSI / SI received by the CPU 13.
[0017]
The remote control transmitter 10 is a transmitter for sending a command to the broadcast receiving device 30. The remote control transmitter 10 is provided with a power key, a channel designation key, a direction key, a determination key, and the like. When keys provided on the remote control transmitter 10 are operated, signal light (remote control signal) indicating a command corresponding to the keys is transmitted from a light emitting unit (not shown). The remote control light receiver 11 receives the signal light, converts it into an electric signal, and gives it to the CPU 13.
[0018]
Various information such as a boot program, a download program, and common data is stored in the nonvolatile memory (for example, a flash memory) 14A. When the power is turned on, the CPU 13 executes from a boot program written in the nonvolatile memory 14A and performs initialization necessary for the system. Then, the program in the nonvolatile memory 14A is expanded to the volatile memory 14B, and the CPU 13 executes the program expanded to the volatile memory 14B. The common data is expanded to the volatile memory 14B by the program initialization routine.
[0019]
The power control circuit 23 receives AC power from a power outlet, generates various DC power by rectification / step-down operation, and supplies it to each circuit. Further, the power control circuit 23 has a timer function, and supplies power to necessary circuits when the date and time (for example, download execution date and time) set by the CPU 13 arrives.
[0020]
The CPU 13 performs a program selection process by the user using the remote control transmitter 10 and the like, a process for displaying an EPG screen for the program selection process, a process when receiving download transmission information (notification information), and a download. A process of writing a program, data, or the like when it is performed to the nonvolatile memory 14A is performed. The process for receiving the download transmission information includes download transmission information (corresponding model information (model_id), version of the downloaded data (version_id), information indicating the module to be acquired, transmission schedule, etc.). , Determining whether the download data is valid, determining a module to be acquired, and storing information indicating the module to be acquired in the nonvolatile memory 14A. For example, the information indicating the module to be acquired is described as “receives the 0th module and the 20th module when the version of the receiver software is“ 0 ””. The module to be acquired is determined based on the software version number.
[0021]
FIG. 2 shows an example of the module. This module includes a plurality of sets each including a header portion and a rewrite data portion. The header part stores at least a write address and write size information. In this embodiment, CRC (error correction) data is added to the header to cope with transmission errors, and corresponding version information (for example, version “0”, version “0”, “1”, etc.) Is added. If no corresponding version information is provided, a module may be created for each version. The rewrite data portion is set to a size equal to or smaller than the write size in the nonvolatile memory 14A.
[0022]
When the power supply control circuit 23 determines the arrival of the execution date and time by the timer function, it energizes the circuits (including the CPU 13 of course) necessary for executing the download. At this time, the CPU 13 is non-volatile. Information indicating that execution of the download process is requested is acquired from the memory 14A, channel selection by the tuner 2 and information separation process by the demultiplexer 3 are performed, download data is acquired, and temporarily stored in a cache memory (not shown). . Here, when the download data (module) has a header for each unit data within a predetermined size as shown in FIG. 2, the CPU 13 is nonvolatile to write based on the start address information in the header. The recording start address of the memory 14A is determined. For example, if the start address is the address itself in the nonvolatile memory 14A (if it is determined as such), the CPU 13 may perform a process of writing rewrite data using the start address as the recording start address. If the start address is information such as the number of bytes from the top address of the software, the recording start address may be calculated from the information, and the rewrite data may be written from the calculated recording start address.
[0023]
Download data (corrected software, update data, etc.) is created by the manufacturer of the digital broadcast receiving device, and the program structure and data structure in the nonvolatile memory in the company's own digital broadcast receiving device are grasped. Thus, the start address information can be obtained without problems. In the digital broadcast receiving apparatus, when a non-volatile memory 14 such as a flash memory that can be written only in a predetermined unit is used, the size of the rewrite data is created in the predetermined unit. In addition, when the amount of data to be downloaded becomes small in this way, the digital broadcast receiving apparatus 30 can be configured to execute download in accordance with a user instruction while the power is on. Here, the conventional download is generally performed when the power of the digital broadcast receiving apparatus is turned off. However, when the amount of data to be downloaded is reduced, the memory usage and the processing load on the CPU 13 can be reduced, and the power is turned on. It can be downloaded without problems even when in the state (when the user is watching TV).
[0024]
【The invention's effect】
As described above, according to the present invention, for example, a part of software is rewritten instead of rewriting the entire software, so that the same data is not repeatedly written to the recording medium. be able to. Furthermore, the capacity of the memory that temporarily caches download data can also be reduced. Further, in the transmission for downloading, it is possible to avoid waste of the transmission band.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a digital broadcast receiving apparatus according to an embodiment of the present invention.
FIG. 2 is an explanatory diagram showing a configuration of a downloaded module.
[Explanation of symbols]
1 Antenna 2 Tuner 3 Demultiplexer (DEMUX)
4 AV decoder 10 Remote control transmitter 13 CPU
14A nonvolatile memory 14B volatile memory 23 power supply control circuit

Claims (2)

In a digital broadcast receiving apparatus configured to receive a digital broadcast wave, demodulate and download data,
A rewritable nonvolatile semiconductor memory in which data is rewritten in a predetermined unit of a part of the memory,
Means for determining a write start address of the nonvolatile semiconductor memory to be written based on start address information in the header when the downloaded data has a header for each unit data constituting a part of software; ,
Means for writing the unit data to the nonvolatile semiconductor memory from the determined write start address ,
Digital broadcasting receiver, wherein the unit same as to Rukoto the size of the data that constitutes a part of a size and software of the predetermined unit of the nonvolatile semiconductor memory. 2. The digital broadcast receiving apparatus according to claim 1, further comprising means for determining the unit data for its own device based on the corresponding version information in the header .

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