Patent Publication Number: US-2006008244-A1

Title: Electronic apparatus

Description:
CROSS REFERENCES TO RELATED APPLICATIONS  
      The present invention contains subject matter related to Japanese, Patent Application JP 2004-203576 filed in the Japanese Patent Office on Jul. 9, 2004, the entire contents of which being incorporated herein by reference.  
     BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to an electronic apparatus for storing input content data in a memory means, then, reproducing and outputting the same.  
      2. Description of the Related Art  
      In recent years, due to recording media becoming large in capacity and development of compression techniques for music, moving pictures and still images, etc., it is possible to store enormous amounts of content data in a recording medium in a portable and other type of reproducing apparatus.  
      Such a reproducing apparatus receives content data, for example, from a personal computer in a state of being connected to the personal computer and stores the same in the recording medium.  
      Also, the reproducing apparatus performs processing of reading content data from recording media, decoding the same and outputting as audio and video in response to an operation signal.  
      In the above reproducing apparatus of the related art, an operation of writing content data input from a personal computer to a recording medium, an operation of reading content data from the recording medium at the time of reproducing, and other control of the reproducing apparatus are performed integrally by one CPU.  
      [Patent Article 1] The Japanese Unexamined Patent Publication No. 2003-132660  
     SUMMARY OF THE INVENTION  
      However, in the reproducing apparatus explained above, an amount of processing by the CPU is large and it is necessary to use a CPU with a high operation frequency.  
      Therefore, the above reproducing apparatus has a disadvantage that the power consumption is too high to use it as a portable apparatus.  
      It is desired to provide an electronic apparatus capable of performing processing of writing input content data to a memory means, then, reading and reproducing the same with a smaller power consumption comparing with that in the related art.  
      To solve the above disadvantages of the related art explained above, according to a first invention, there is provided an electronic apparatus, having an interface for receiving content data; a memory means connected to a data transfer bus, for storing the content data; a first control circuit for writing content data input via the interface to the memory means via the data transfer bus; a reproduction circuit for reproducing the content data; a second control circuit for reading the content data from the memory means via the data transfer bus and outputting to the reproduction circuit; and a third control circuit for performing outputting processing of the content data reproduced by the reproduction circuit.  
      According to a second invention, there is provided a electronic apparatus, having an interface for receiving content data; a memory means connected to a data transfer bus, for storing the content data; a first control circuit for writing content data input via the interface to the memory means; a reproduction circuit for reproducing the content data; a second control circuit for reading the content data from the memory means and outputting the same to the reproduction circuit; and a third control circuit for performing outputting processing of the content data reproduced by the reproduction circuit; wherein the third control circuit makes the first control circuit to be in a driving state and makes the second control circuit to be in a non-driving state when receiving the content data via the interface, and makes the reproduction circuit and the second control circuit to be in a driving state and makes the first control circuit to be in a non-driving state when reading content data from the memory means and reproducing the same.  
      According to the present invention, an electronic apparatus capable of performing processing of writing input content data to a memory means, then, reading and reproducing the same with a smaller power consumption comparing with that in the related art can be provided. 
    
    
     BRIEF DESCRIPTION OF DRAWINGS  
      These and other objects and features of the present invention will become clearer from the following description of the preferred embodiments given with reference to the attached drawings, in which:  
       FIG. 1  is a view for explaining relationship of a portable audio reproducing apparatus and a personal computer according to an embodiment of the present invention;  
       FIG. 2  is a view of the configuration of the portable audio reproducing apparatus shown in  FIG. 1 ;  
       FIG. 3  is a view of the configuration of a USB control portion shown in  FIG. 2 ;  
       FIG. 4  is a view of an appearance of the portable audio reproducing apparatus shown in  FIG. 1 ;  
       FIG. 5  is a view for explaining various screens displayed on the portable audio reproducing apparatus shown in  FIG. 2 ;  
       FIG. 6  is a view of the configuration of a gate array of the portable audio reproducing apparatus shown in  FIG. 1 ;  
       FIG. 7  is a view of the configuration of a microcomputer of the portable audio reproducing apparatus shown in  FIG. 1 ;  
       FIG. 8  is a disassembled perspective view of a part of the portable audio reproducing apparatus shown in FIG.  
       FIG. 9  is a view for explaining shifts of a song select screen displayed on an LCD of the portable audio reproducing apparatus shown in  FIG. 2 ; and  
       FIG. 10  is a view continued from  FIG. 9 , for explaining shifts of a song select screen displayed on the LCD of the portable audio reproducing apparatus shown in  FIG. 2 . 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
      Below, an embodiment of the present invention will be explained with reference to  FIG. 1  to  FIG. 10 .  
      A reproducing apparatus according to an embodiment of the present invention will be explained first.  
       FIG. 1  is a view for explaining relationship of a portable audio reproducing apparatus  1  and a personal computer  3  according to an embodiment of the present invention.  
      The portable audio reproducing apparatus  1  is connected to, for example, the personal computer  3  in a removable wav.  
      The portable audio reproducing apparatus  1  receives as an input song data (content data) from the personal computer  3  in a state of being connected to the personal computer  3  and writes the same to a built-in HDD.  
      Also, the portable audio reproducing apparatus  1  decodes and reproduces the song data read from the HDD, for example, in a state of not connected to the personal computer  3 .  
       FIG. 2  is a view of the configuration of the portable audio reproducing apparatus  1  shown in  FIG. 1 .  
      As shown in  FIG. 2 , the portable audio reproducing apparatus  1  includes, for example, a PC interface  10 , a USB (Universal Serial Bus) control portion  12 , an LCD (Liquid Crystal Display)  14 , an LCD control portion  16 , an HDD (Hard Disk Drive)  17 , a gate array  18 , an SDRAM (Synchronous DRAM)  20 , a decoder  22 , a flash memory  24 , a microcomputer  26 , an amplifier  28 , an operation portion  30 , a G sensor  32 , an audio output terminal  46 , a remote controller terminal  47 , a data transfer bus  51 , a control bus  53 , a control and data transfer bus  55 , an oscillation circuit  57 , an oscillation circuit  59  and a power source  60 .  
      Below, connection relationship of the components of the portable audio reproducing apparatus  1  shown in  FIG. 2  will be explained.  
      As shown in  FIG. 2 , the data transfer bus  51  is connected to the USB control portion  12 , the HDD  17  and the gate array  18 .  
      The USB control portion  12 , the HDD  17  and the gate array  18  obtain right of use the data transfer bus  51  by arbitration. The right of use the data transfer bus  51  can be obtained by only one of the USB control portion  12 , the HDD  17  and the gate array  18  at a time.  
      The control bus  53  is connected to the USB control portion  12 , the LCD control portion  16  and the gate array  18 .  
      The USB control portion  12 , the LCD control portion  16  and the gate array  18  obtain right of use the control bus  53  by arbitration. The right of use the control bus  53  can be obtained by only one of the USB control portion  12 , the LCD control portion  16  and the gate array  18  at a time.  
      The control and data transfer bus  55  is connected to the gate array  18 , the flash memory  24  and the microcomputer  26 .  
      The gate array  18  and the microcomputer  26  obtain right of use the control and data transfer bus  55  by arbitration. The right of use the control and data transfer bus  55  can be obtained by only one of the gate array  19  and the microcomputer  26  at a time.  
      Note that the data transfer bus  51  and the control and data transfer bus  55  are 16-bit width, and the control bus  53  is 8-bit width.  
      Below, the respective components shown in  FIG. 2  will be explained.  
      [PC Interface  10 ] 
      The PC interface  10  is connected to the personal computer  3  via a USB cable in a removable way.  
      The PC interface  10  receives song data from the personal computer  3  and outputs the same to the USB control portion  12  in a state of being attached with the USB cable.  
      [USB Control Portion  12 ] 
      The USB control portion  12  writes content data input via the PC interface  10  to the HDD  17  via the data transfer bus  51 .  
      Also, the USB control portion  12  outputs a control signal input via the PC interface  10  to the gate array  18  via the control bus  53 .  
       FIG. 3  is a view of the configuration of the USB control portion  12  shown in  FIG. 2 .  
      As shown in  FIG. 3 , the USB control portion  12  includes, for example, an SRAM  101 , an interface  103 , an IDE (Integrated Drive Electronics)/DMA (Direct Memory Access)  105  and a FIFO (First In First Out) control circuit  107 .  
      The SRAM  101  temporarily stores, for example, song data input from the personal computer  3  via the PC interface  10 .  
      The interface  103  is connected to the control bus  53 .  
      The IDE/DMA  105  is connected to the data transfer bus  51  and controls inputting/outputting of song data between the PC interface  10  and the HDD  17 .  
      The FIFO control circuit  107  integrally controls an operation of the USB control portion  12 , which will be explained in the present embodiment.  
      [LCD  14  and LCD Control Portion  16 ] 
      The LCD  14  is provided, for example as shown in FIG.  4 , on the surface side of a chassis of the portable audio reproducing apparatus  1 .  
      The LCD control portion  16  displays a predetermined screen on the LCD  14  based on a display control signal input from the microcomputer  26  via the control and data transfer bus  55 , the gate array  18  and the control bus  53 .  
      The LCD control portion  16  displays on the LCD  14 , for example, a song select screen D 1  shown in  FIG. 5A , a setting screen shown in  FIG. 5B  and a reproduction screen shown in  FIG. 5C .  
      [HDD 17 ] 
      The HDD  17  has a memory capacity of, for example, 20 GB and is capable of storing song data of about 10000 songs (an amount of  700  compact disks) compressed by the ATRAC (Adaptive Transform Acoustic Coding), etc.  
      Each song data of an amount of one song (hereinafter, also simply referred to as song data) stored in the HDD  17  is added with attributes data on the artist, album, style, group, new track and bookmark, etc.  
      [Gate Array  18 ] 
      The gate array  18  reads song data to be reproduced from the HDD  17  via the data transfer bus  51  and outputs the same to the decoder  22 .  
      Also, the gate array  18  receives as an input a control signal from the USB control portion  12  via the control bus  53  and outputs the same to the microcomputer  26  via the control and data transfer bus  55 .  
       FIG. 6  is a view of the configuration of the gate array  18  shown in  FIG. 2 .  
      As shown in  FIG. 6 , the gate array  18  includes, for example, an interface  111 , an interface  113 , a control circuit SDRAMC  115 , an interface  117 , a DMAC  119 , and interface  121  and the TSB  125  connected via a bus  110 .  
      The gate array  18  performs, for example, processing of writing song data input from the personal computer  3  to the HDD  17  and processing of reading specified song data from the HDD  17 . Consequently, a load of processing imposed on the microcomputer  26  can be reduced comparing with that in the case of the related art, where all of the above processing is performed by the microcomputer  26 .  
      The interface  111  is connected to the control bus  53 .  
      The interface  113  is connected to the data transfer bus  51 .  
      The control circuit SDRAMC  115  temporarily stores in the SDRAM  20  song data input from the HDD  17  via the interface  113 .  
      The interface  117  is connected to the control and data transfer bus  55 .  
      The DMAC  119  integrally controls an operation of the gate array  18 , which will be explained in the present embodiment.  
      The interface  121  outputs song data read from the SDRAM  20  to the decoder  22 .  
      The TSB  125  receives as an input an operation signal generated by a not shown remote controller in response to an operation by a user via the remote controller terminal  47 .  
      [SDRAM  20 ] 
      The SDRAM- 20  stores song data read from the HDD  17  by the gate array  18 .  
      [Decoder  22 ] 
      The decoder  22  decodes song data input from the gate array  18 , generates a digital song signal, and outputs the same to the microcomputer  26 .  
      The song data is encoded, for example, by the ATRAC as explained above, and the decoder  22  performs decoding corresponding to that.  
      Also, the decoder  22  performs surround processing and PCM (Pulse Code Modulation) conversion processing, etc. other than the decoding as above.  
      [Flash Memory  24 ] 
      The flash memory  24  stores a program executed by the microcomputer  26 .  
      [Microcomputer  26 ] 
      The microcomputer  26  integrally controls an operation of the portable audio reproducing apparatus  1 .  
      For example, in the case of writing song data input via the PC interface  10  to the HDD  17 , the microcomputer  26  makes the USB control portion  12  to be in a driving state and makes the gate array  18  to be in a non-driving state.  
      Also, when reading song data from the HDD  17  and reproducing the same, the microcomputer  26  makes the USB control portion  12  to be in a non-driving state and makes the gate array  18  and the decode  22  to be in a driving state.  
       FIG. 7  is a view of the configuration of the microcomputer  26  shown in  FIG. 2 .  
      As shown in  FIG. 7 , the microcomputer  26  includes, for example, an interface  131 , an interface  133 , a DAC (Digital Analog Converter)  135 , an ADC (Analog Digital Converter)  137 , an SDRAM  139 , a DMAC  141  and a CPU  143 .  
      The interface  131  is connected to the control and data transfer bus  55 .  
      The interface  133  is connected to the decoder  22 , outputs a control signal to the decoder  22  and controls decoding processing by the decoder  22 .  
      The DAC  135  converts the digital song signal input from the decoder  22  to an analog song signal and outputs the same to the amplifier  28 .  
      The ADC  137  converts an analog operation signal input from the operation portion  30  and an analog sensor signal input from the G sensor respectively to a digital operation signal and a digital sensor signal, and outputs them to the CPU  143 .  
      Note that the G sensor  32  detects acceleration of the portable audio reproducing apparatus  1  and outputs a G sensor signal indicating the detection result to the ADC  137 .  
       FIG. 4A ,  FIG. 4B  and  FIG. 4C  are a view from above, a view from front and a view from below of the portable audio reproducing apparatus  1 , respectively.  
      In the present embodiment, the operation portion  30  includes, for example, a MENU key  64 , a MODE key  65  and a VOLUME key  66  shown in  FIG. 4A , a cross right key  67   a , a cross left key  67   b , a cross upper key  67   c , a cross lower key  67   d  and a cross decision key  67   e  shown in  FIG. 4B , and a HOLD key  68  shown in  FIG. 4C .  
      The SDRAM  139  temporarily stores data to be processed by the CPU  143 , such as codes of a program read from the flash memory  24 .  
      The DMAC  141  controls an access to the HDD  17  by the gate array  18 .  
      The CPU  143  calls up a program from the flash memory  24  via the interface  131  and the control and data transfer bus  55 , and integrally controls processing of the microcomputer  26  based on the program.  
      The CPU  143  determines whether the portable audio reproducing apparatus  1  starts to drop or not, for example, based on the G sensor signal explained above, and performs processing of making a head of the HDD  17  receded when determined that it starts to drop.  
      Also, the CPU  143  monitors a data amount of song data stored in the SDRAM  20  and, when the data amount becomes a predetermined threshold value or smaller makes the gate array  18  to restart reading of song data from the HDD  17 .  
      [Power Source  60 ] 
      The power source  60  supplies drive power to the respective components of the portable audio reproducing apparatus  1 .  
      Note that the gate array  18 , the decoder  22  and the microcomputer  26  shown in  FIG. 2  operate based on a drive signal having a frequency of 22.5 MHz given from the oscillation circuit  57 .  
      Also, the USB control portion  12  operates based on a drive signal having a frequency of 12 MHz given from the oscillation circuit  59 .  
      Below, the configuration of the portable audio reproducing apparatus  1  of the present embodiment will be explained.  
       FIG. 8  is a disassembled perspective view of the portable audio reproducing apparatus  1  of the present embodiment.  
      Note that only a part of the portable audio reproducing apparatus  1  is shown in  FIG. 8 .  
      As shown in  FIG. 8 , in the portable audio reproducing apparatus  1 , after the LCD  14  and the power source  60  are mounted on a body holder  76 , the body holder  76  is placed inside a cabinet  75  from an opening portion  75   a.    
      After that, a cap portion  77  is attached to the body holder  76  to close up the opening portion  75   a.    
      Also, the cabinet  75  is formed with an opening portion  75   b  at a position corresponding to the LCD  14 .  
      After this operation, an adhesive sheet  73  formed with an opening portion at a position corresponding to the LCD  14  is adhered to the cabinet  75 .  
      After that, translucent or semi-translucent plate  72  is adhered to the adhesive sheet  73 .  
      The plate  72  is formed with an opening portion  72   a , where the cross right key  67   a , cross left key  67   b , cross upper key  67   c , cross lower key  67   d  and cross decision key  67   e  fit in.  
      Note that, while not illustrated in  FIG. 8 , the body holder  76  is mounted with the HDD  17  shown in  FIG. 2  and a circuit substrate besides the LCD  14  and the power source  60 . On the circuit substrate, the USB control portion  12 , the SDRAM  20 , the decoder  22 , the flash memory  24  and the microcomputer  26  shown in  FIG. 2  are installed.  
      Below, operation examples of the portable audio reproducing apparatus  1  will be explained.  
     First Operation Example  
      In this operation example, the case of downloading song data from the personal computer  3  to the portable audio reproducing apparatus  1  will be explained.  
      Note that when the portable audio reproducing apparatus  1  detects that the PC  3  is connected to the PC interface  10 , it automatically downloads song data, which is not stored in the HDD  17 , from song data stored in the PC  3 .  
      First, the PC interface  10  of the portable audio reproducing apparatus  1  is connected to the personal computer  3  via the USB cable.  
      The personal computer  3  recognizes (detects) the portable audio reproducing apparatus  1  as a removable HDD.  
      Then, the personal computer  3  outputs song data to the PC interface  10 .  
      The USB control portion  12  shown in  FIG. 2  stores the song data in the SRAM  101  by the FIFO control circuit  107  shown in  FIG. 3 .  
      Continuously, the FIFO control circuit  107  writes the song data read from the SRAM  101  to the HDD  17  via the data transfer bus  51  in response to control by the IDE/DMA  105 .  
      At this time, the FIFO control circuit  107  obtains right of use the data transfer bus  51  by arbitration, then, uses the data transfer bus  51 .  
      The above operation is mainly controlled by the USB control portion  12 , and the microcomputer  26  does not directly involve in the control.  
      As a result, a processing amount of the microcomputer  26  can be reduced, a microcomputer  26  having a lower operation frequency comparing with that of the related art can be used, and the power can be saved.  
     Second Operation Example  
      In this operation example, the case of outputting a control signal from the personal computer  3  to the portable audio reproducing apparatus  1  will be explained.  
      First, the PC interface  10  of the portable audio reproducing apparatus  1  is connected to the personal computer  3  via a USB cable.  
      Then, the personal computer  3  outputs a control signal (command data) in response to a user operation to the PC interface  10 .  
      The USB control portion  12  shown in  FIG. 2  makes the FIFO control circuit  107  shown in  FIG. 3  to store the operation signal in the SRAM  101 .  
      After that, the microcomputer  26  reads the control signal from the SRAM  101  of the USB control portion  12  via the control and data transfer bus  55 , the gate array  18  and the control bus  53 .  
      At this time, the microcomputer  26  obtains right of use the control and data transfer bus  55  by arbitration, then, uses the control and data transfer bus  55 . Also, the gate array  18  obtains right of use the control bus  53  by arbitration, then, uses the control bus  53 .  
      Then, the microcomputer  26  performs predetermined processing based on the read control signal.  
     Third Operation Example  
      In this operation example, the case of reproducing song data stored in the HDD  17  will be explained.  
      For example, the operation portion  30  (for example, the cross decision key  67   e  shown in  FIG. 4 ) outputs a reproducing instruction in response to the user operation to the microcomputer  26 .  
      Then, when receiving the reproducing instruction, the microcomputer  26  outputs a reproducing request specifying song data to be reproduced to the gate array  18  via the control and data transfer bus  55 .  
      At this time, the microcomputer  26  obtains right of use the control and data transfer bus  55  by arbitration, then, uses the control and data transfer bus  55 .  
      After that, the microcomputer  26  becomes free from the reproducing operation.  
      The gate array  18  shown in  FIG. 6  receives as an input the reproducing request via the interface  117  and outputs the same to the DMAC  119 .  
      The DMAC  119  accesses to the HDD  17  via the interface  113  and the data transfer bus  51  and reads song data relating to the above reproducing request.  
      At this time, the gate array  18  obtains right of use the data transfer bus  51  by arbitration, then, uses the data transfer bus  51 .  
      The DMAC  119  of the gate array  18  writes the song data input from the HDD  17  via the interface  113  to the SDRAM  20  via the control circuit SDRAMC  115 .  
      In parallel with the writing operation, the DMAC  119  reads song data from the SDRAM  20  via the control circuit SDRAMC  115  and outputs the same to the decoder  22  via the interface  121 .  
      The decoder  22  decodes (reproduces) the input song data by the ATRAC and outputs a decoded digital song signal to the microcomputer  26 .  
      Also, the decoder  22  notifies the microcomputer  26  of completion of the decoding.  
      The microcomputer  26  receives the decoded digital song signal by the DAC 135  shown in  FIG. 7 , converts the same to an analog song signal in the DAC  135  and outputs to the amplifier  28 .  
      Then, the analog song signal is amplified by the amplifier  28  and output to a headphone via the audio output terminal  46 .  
      In the present operation example, processing from reading song data from the HDD  17  to outputting the same to the decoder  22  is controlled mainly by the gate array  18 , and the microcomputer  26  does not directly involve in the control.  
      As a result, a processing amount of the microcomputer  26  can be reduced, a microcomputer  26  having a lower operation frequency comparing with that of the related art can be used, and the power can be saved.  
     Fourth Operation Example  
      In this operation example, the case where the microcomputer  26  shown in  FIG. 2  makes the LCD  14  to display a song select screen will be explained.  
      First, a song select screen D 1  will be explained.  
      As the song select screen D 1 , a plurality of song select screens on a first layer are regulated, which are regulated with respect to each of the plurality of different attributes (attributes of song data) and display a plurality of items regulated by the attributes to select.  
      Also, as the song select screen D 1 , song select screens on second and lower layers are regulated for each of the song select screens on the first layer.  
      The song select screens on second and lower layers are regulated with respect to each item of the song select screens on its upper layer and has a plurality of items for classifying song data belonging to the item based on the attributes other than the above attributes corresponding to the items.  
      The song select screen D 1  on the first layer is, for example, song select screens D 1 _ 1 , D 1 _ 2 , D 1 _ 3 , D 1 _ 4  and D 1 _ 5  shown in  FIG. 9  and  FIG. 10 .  
      Here, the song select screens D 1 _ 1 , D 1 _ 2 , D 1 _ 3 , D 1 _ 4  and D 1 _ 5  are screens for displaying by classifying song data based on attributes thereof: an Artist, Album, Style, Group and Others, respectively.  
      For example, when a user presses the MODE key  65  shown in  FIG. 4A  in a state where the setting screen D 2 , etc. is displayed on the LCD panel  14 , the microcomputer  26  shown in  FIG. 1  displays the song select screen D 1 _ 1  shown in  FIG. 9  on the LCD panel  14  based on an operation signal from the MODE key  65 .  
      The song select screen D 1 _ 1  displays a plurality of items (artists A, B and C, etc.) for classifying the song data based on an attribute of artists.  
      At this time, the microcomputer  26  may display a song select screen on the first layer other than the song select screen D 1 _ 1  on the LCD panel  14 .  
      Continuously, when the user presses the MODE key  65 , the microcomputer  26  displays the song select screen D 1 _ 2  shown in  FIG. 9  on the LCD panel  14  based on an operation signal from the MODE key  65 .  
      The song select screen D 1 _ 2  displays a plurality of items (albums A, B and C, etc.) for classifying the song data based on an attribute of albums.  
      Continuously, when the user presses the MODE key  65 , the microcomputer  26  displays the song select screen D 1 _ 3  shown in  FIG. 9  on the LCD panel  14  based on an operation signal from the MODE key  65 .  
      The song select screen D 1 _ 3  displays a plurality of items (CLASSIC, J-POP and ROCK, etc.) for classifying the song data based on an attribute of styles.  
      Continuously, when the user presses the MODE key  65 , the microcomputer  26  displays the song select screen D 1 _ 4  shown in  FIG. 10  on the LCD panel  14  based on an operation signal from the MODE key  65 .  
      The song select screen D 1 _ 4  displays a plurality of items (groups A, B and C, etc.) for classifying the song data based on an attribute of groups regulated by the personal computer  3 .  
      Continuously, when the user presses the MODE key  65 , the microcomputer  26  displays the song select screen D 1 _ 5  shown in  FIG. 10  on the LCD panel  14  based on an operation signal from the MODE key  65 .  
      The song select screen D 1 _ 5  displays a plurality of items for classifying the song data based on other attributes, such as “New Tracks” indicating newly input tracks (song data) from the personal computer  3  and “Bookmark” indicating that a bookmark is put by the user.  
      Continuously, when the cross right key  67   a  is pressed on the song select screen D 1 _ 5 , the microcomputer  26  displays the song select screen D 1 _ 51  showing titles of song data registered in the new song folder.  
      Continuously, when a cursor is moved vertically on the song select screen D 1 _ 51  to point a desired title and a cross decision key  67   e  is pressed, the microcomputer  26  displays a reproduction screen D 3  of the title on the LCD panel  14  and reproduces the same.  
      As explained above, in the portable audio reproducing apparatus  1 , as explained in the above first operation example, an operation of writing song data input from the personal computer  3  to the HDD  17  is controlled mainly by the USB control portion  12 .  
      Also, in the portable audio reproducing apparatus  1 , as explained in the above third operation example, processing of reading song data from the HDD  17  and outputting to the decoder  22  is controlled mainly by the gate array  18 .  
      As a result, according to the portable audio reproducing apparatus  1 , comparing with the case where both of the above processing are performed by the microcomputer as in the related art, a processing load imposed on the microcomputer  26  can be reduced. Therefore, according to the portable audio reproducing apparatus  1 , a microcomputer  26  having a lower operation frequency comparing with that of the related art can be used, and the power can be saved.  
      Also, according to the portable audio reproducing apparatus  1 , in the case of writing song data input via the PC interface  10  to the HDD  17 , the decoder  22  and the gate array  18  are made to be in a non-driving state, while in the case of reproducing song data read from the HDD  17 , the USB control portion  12  is made to be in a non-driving state. Consequently, furthermore power saving can be attained.  
      Also, in the portable audio reproducing apparatus  1 , the USB control portion  12 , the HDD  17  and the gate array  18  are connected to the data transfer bus  51 , and only one of the USB control portion  12  and the gate array  18  that obtained right of use the data transfer bus  51  by arbitration is capable of accessing to the HDD  17 . Therefore, it is not necessary to provide interfaces respectively to the USB control portion  12  and the gate array  18  in the HDD  17 , and the same configuration as that in the related art can be used.  
      The present invention is not limited to the above embodiment.  
      In the above embodiment, the case of applying the present invention to the portable audio reproducing apparatus was explained as an example, but the present invention can be also applied to personal computer and other apparatuses other than portable apparatuses.  
      Also, in the present invention, as a memory means for storing content data, instead of the HDD  17  shown in  FIG. 2 , an MD (registered trademark) and other magneto-optical recording media, a CD-R (CD-Recordable), DVD-R (DVD-Recordable) and other optical recording media, a memory stick (registered trademark), SD card (registered trademark) and other semiconductor memories may be used.  
      Also, in the above embodiment, audio data, such as song data, was explained as an example of content data of the present invention, but it may be image data, such as a video and picture.  
      Also, in the above embodiment, a portable audio reproducing apparatus  1  was explained as an example of an electronic apparatus of the present invention, but the electronic apparatus of the present invention may be, for example, a personal computer, an optical disk reproducing apparatus for a compact disk, etc., and a magneto-optical disk reproducing apparatus, etc.  
      The present invention can be applied to a system for storing input content data in a memory means, then decoding and outputting the same.  
      It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and alternations may occur depending on design requirements and other factors insofar as they are within the scope of the appended claims or the equivalents thereof.