Patent Publication Number: US-2005117550-A1

Title: Information processing device

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates to an information processing device and in particular to an information processing device having a communication function.  
      2. Description of the Related Art  
      Recently, cdma2000 1xEV-DO (hereinafter referred to as EV-DO) has been developed as a next-generation high-rate radio communication system. The EV-DO is a new version of specializing cdma2000 1x system provided by expanding cdma2000 to the third-generation system for data communications and increasing the transmission rate. “EV” means Evolution, and “DO” means Data Only.  
      The EV-DO system is approximately the same as the cdma2000 1x system in the configuration of a radio interface of an upstream channel from a radio communication terminal to a base station. As for the configuration of the radio interface of a downstream channel from a base station to a radio communication terminal, whereas the bandwidth of 1.23 MHz is the same with that of the cdma2000 1x system, the modulation method and the multiplexing method are much different from those of the cdma2000 1x system. As for the modulation method, whereas QPSK and HPSK are used in the cdma2000 1x system, QPSK, 8-PSK, or 16QAM is selectively used in the EV-DO system according to a reception state of a downstream channel of a radio communication terminal. As a result, a high transmission rate with low error resistance is used when the reception state is good, and a low transmission rate with high error resistance is used when the reception state is bad.  
      As for the multiplexing method for enabling multiple communications from one base station to a plurality of radio communication terminals, TDMA (Time Division Multiple Access) is employed in which communications with a plurality of radio communication terminals are performed in such a manner that time is divided in units of {fraction (1/600)} second, a communication is performed with one radio communication terminal in each unit time, and the radio communication terminal to be communicated is switched every unit time, rather than CDMA (Code Division Multiple Access) which is employed in the cdmaOne system and the cdma2000 1x system.  
      A radio communication terminal measures a carrier-to-interference power ratio (hereinafter abbreviated as CIR) of a pilot signal as an index of a reception state of a downstream channel from a base station to be communicated, predicts a reception state during the next reception time slot on the basis of a variation of the CIR, and notify “a maximum transmission rate which enables to receive with a error ratio that is lower than a predetermined rate”, which is expected from the predicted reception state to the base station as data rate control bits (hereinafter referred to as DRC)predetermined. The predetermined error rate is usually set to about 1% though it depends on the system design. The base station receives the DRCs from a plurality of radio communication terminals, and a scheduler function in the base station determines with which radio communication terminal is to communicate in each division unit time. Basically, as high a transmission rate as possible is decided on the basis of a DRC sent from each radio communication terminal and is used for a communication with it.  
      With the above configuration, the EV-DO system enables a maximum transmission rate of 2.4 Mbps (mega-bits per second) per sector in a downstream channel. This transmission rate is the sum of amounts of data communications from one base station to a plurality of radio communication terminals in one frequency band and in one of a plurality of sectors (usually, a plurality of sectors exist). The transmission rate increases if a plurality of frequency bands are used.  
      JP-A-2002-300644 is known as a related art.  
      A cellular phone of cdma2000 1x, etc., has identification information such as subscriber information unique to each terminal assigned by a common carrier, etc., generally for the purposes of valid connection to a radio telephone network, charging management, and the like. Such subscriber information is usually written into the terminal in the shop when the cellular phone is sold. Before the subscriber information is written, for example, one end of a serial communication line to enter the subscriber information is connected to a 16-condcutor connector provided at a terminal of a PDC or an 18-conductor connector provided at a terminal of cdmaOne or cdma2000 1x, and the other end of the serial communication line is connected to a personal computer (PC), etc. Further, communications are performed between the PC, etc., and the terminal according to a predetermined procedure, and the operator, etc., of the common carrier writes the subscriber information into the terminal.  
      Since the EV-DO is mainly intended for data communications, a PC or a PDA is excellent in operability rather than a cellular phone as the form of a terminal used by the user. Particularly, the PDA is generally small and is excellent not only in operability but also in portability. To realize such a form, for example, a communication module of a rectangle with one side about several centimeters and having a thickness of about several millimeters to ten several millimeters and having a communication function of the EV-DO is included in the PDA.  
      It is difficult to provide a coupling connector for writing subscriber information to the communication module with the communication module because of size restriction of these. It is necessary to supply power to the communication module in order to write the subscriber information into the communication module, or the subscriber information cannot be written into the communication module without the power supply. Therefore, the communication module is taken out from the PDA and is placed in a writer of subscriber information and after the subscriber information is written into the communication module, the communication module is taken out from the writer and is again installed in the PDA. This procedure is intricate and at the same time, there is a fear of degrading the reliability of the connection of a board of the PDA and the communication module because the communication module is detached from and again attached to the PDA.  
      A connection terminal of the coupling connector may be provided at the main body of the PDA to connect the connection terminal and the communication module by a signal line. However, since the size of the PDA is small, preferably the area occupied by the signal line in the PDA should be smaller. If the signal line is also connected to a CPU of the PDA, there is a possibility that the subscriber information may be entered in the CPU. In such a case, it is also feared that the subscriber information may be abused. Therefore, a configuration to prevent the signal line from being input to the CPU is required from the viewpoints of security and management of the common carrier.  
     SUMMARY OF THE INVENTION  
      The object of the invention is to provide an information processing device provided with a terminal for externally inputting a predetermined information for enabling the information to be input to a communication module with safety.  
      The invention provides an information processing device, having: a connection terminal, which is connected to a first signal line, to connect an external device to the information processing device; a control section, which is connected to a second signal line whose transfer speed is different from a transfer speed of the first signal line, for performing various processes of the information processing device; a communication section, which is connected to a third signal line to be connected the first signal line or the second signal line, for performing a communication process based on a subscriber information; and a switching section for switching a connection of the third signal line to one of the first signal line and the second signal line, wherein the switching section connects the third signal line to the first signal line when the external device is connected to the connection terminal so that the subscriber information enables to be input from the external device, and connects the third signal line to the second signal line when the communication section performs the communication process.  
      The term “switch” may include the case where the connection is switched by a physical switch and the case where the connection is switched by a logical or electronic switch; a predetermined input signal may be output to either.  
      According to the information processing device, when the subscriber information is stored in the communication section, the switch section connects the communication section and the connection terminal. Therefore, the subscriber information can be input only to the communication section. On the other hand, where communication is executed by the communication section, the control section is connected to the communication section through a signal line of a high transfer speed. Therefore, the signal transfer at the high speed can be realized.  
      The transfer speed of the second signal line may be higher than the transfer speed of the first signal line. The control section may output a signal for instructing the switching section to switch the connection of the third signal line, and the switching section may connect the third signal line to the first signal line or the second signal line according to the signal instructed the switching section to switch the connection of the third signal line. The information processing device may further has: a connection detecting section for detecting connection of the external device and the connection terminal, wherein the switching section may switch the connection of the third signal line according to a detection result of the connection detecting section.  
      The information processing device may further has: a power control section for controlling power supply to the control section, wherein the power control section may stop the power supply to the control section when the switching section connects the first signal line to the third signal line. The information processing device may further has: a power control section for controlling power supply to the control section, wherein when the power control section may start the power supply to the control section, the switching section may connect the second signal line to the third signal line, and when the power control section stops the power supply to the control section, the switching section may connect the first signal line to the third signal line. The information processing device may further have: a notification section for notifying a user of the information processing device of a predetermined message according to the connection of the third signal line. The communication section may be a communication module.  
      Conversion of any desired combination of the components described above and the representation of the invention among methods, apparatuses, systems, record media, computer programs, etc., is also effective as an aspect of the invention.  
      According to the invention, there can be provided the information processing device provided with a terminal for externally inputting a predetermined information for enabling the information to be input to a communication module with safety. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a block diagram to show the configuration of an information processing device according to a first embodiment of the invention;  
       FIGS. 2A and 2B  are drawings to show the back and the face of the appearance of the information processing device in  FIG. 1 ;  
       FIG. 3  is a drawing to show an example of display of a display section in  FIG. 1 ;  
       FIG. 4  is a block diagram to show the configuration of an information processing device according to a second embodiment of the invention;  
       FIG. 5  is a block diagram to show the configuration of an information processing device according to a third embodiment of the invention;  
       FIG. 6  is a block diagram to show the configuration of an information processing device according to a fourth embodiment of the invention; and  
       FIG. 7  is a block diagram to show the configuration of an information processing device according to a fifth embodiment of the invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
     First Embodiment  
      A first embodiment of the invention relates to an information processing device incorporating a communication module. The information processing device has a CPU for executing various processing other than a communication processing. Usually, if the user operates to execute a program stored in a storage area in the information processing device, the CPU executes processing of the program. On the other hand, if the user operates to execute the communication processing, the communication module conducts communications solely and thus the CPU transmits information to be communicated to the communication module via a signal line between the CPU and the communication module. The communication module stores subscriber information therein and uses the stored subscriber information in conducting communications.  
      Therefore, it is necessary to store the subscriber information in the communication module prior to communication processing. The information processing device of the embodiment has a switch section positioned between the CPU and the communication module. The switch section includes three terminals, two of which are respectively connected to the CPU and the communication module, and the remaining one is connected to a connection terminal provided on a cabinet of the information processing device. In usual processing, the switch section connects the CPU and the communication module. In writing subscriber information into the communication module, the switch section connects the connection terminal and the communication module. Consequently, the subscriber information is prevented from being transmitted to the CPU.  
      Between the communication module and the connection terminal, the subscriber information is only transferred so that high transfer speed is not required. On the other hand, between the communication module and the CPU, data to be communicated is transferred so that higher transfer speed is desired. Thus, if a plurality of signal lines are prepared for those, the number of the signal lines increases as well as the number of terminals for the signal lines attached to the communication module also increases. In the embodiment, signal lines are shared, the function of the signal lines is switched or changed or selected by the communication module according to the operation of the switch section.  
       FIG. 1  shows the configuration of an information processing device  100  according to the first embodiment. The information processing device  100  includes a connection terminal  10 , a CPU  12 , a switch section  14 , a switch  18 , a memory  20 , a display section  22 , an operation section  24 , and a notification section  26 . The communication module  16  includes a communication CPU  28 , communication memory  30 , a processing section  32 , an RF section  34 , and an in-module switch section  60 . The switch section  14  includes contacts A to F, and the in-module switch section  60  includes contacts G to L. The information processing device  100  also includes module signal lines  200  as signal lines. An external device  110  and an external device terminal  36  exist outside the information processing device. Further, a communication module  16  provided as a different unit from the information processing device  100  is connected with the information processing device  100 .  
      The CPU  12  executes various processing that can be executed in the information processing device  100 . Particularly, the CPU  12  executes a program stored in the memory  20  in conjunction with the memory  20 . For example, the program is document preparation, schedule management, mail client, etc. The memory  20  may temporarily store the program or may store the program until the program is deleted according to a predetermined instruction.  
      The communication module  16  executes communication processing based on EV-DO or cdma2000 1x. The RF section  34  executes transmission and reception processing of a radio signal, the processing section  32  executes modulation and demodulation processing of a baseband signal, spread processing and inverse spread processing, error correction processing, retransmission processing, etc. The communication CPU  28  executes control processing in the RF section  34  and the processing section  32 . Further, subscriber information such as a telephone number provided by a common carrier, etc., is stored in the communication memory  30 , and is read particularly by the communication CPU  28  as required. The in-module switch section  60  operates in synchronization with the switch section  14  on the basis of an instruction from the switch  18 .  
      The connection terminal  10  is an 18-conductor coupling connector defined for EV-DO and cdma2000 1x cellular phones, and includes an asynchronous serial communication signal line. For a cdmaOne, cdma2000 1x cellular phone communication terminal, two asynchronous serial communication signal lines are defined in an 18-conductor coupling connector, and one of the signal lines is used to write subscriber information. In the case of PDC, an asynchronous serial signal line is also defined in a 16-conductor coupling connector and is used to write subscriber information. A signal line with a higher speed than a USB signal line may be used in place of the asynchronous serial communication signal line.  
      The switch section  14  switches signal lines from the communication module  16  to the CPU  12  or the connection terminal  10 . The switch section  14  can switch between connection of the CPU  12  and the communication module  16  and connection of the connection terminal  10  and the communication module  16 . An explanation will be given of the connection of the signal lines among the CPU  12 , the communication module  16  and the connection terminal  10  by the switch section  14  and the in-module switch section  60 . The CPU  12  is coupled with four signal lines and the communication CPU  28  is coupled with six signal lines. A first module signal line  200   a  and a fourth module signal line  200   d  which are two lines of those signal lines correspond to VBUS (power source) and GND (grounding) directly coupling the CPU  12  and the communication CPU  28 , respectively.  
      The switch section  14  includes terminals A to F. The terminals B and E coupled with the CPU  12  correspond to D+ and D− of a bi-directional signal line, respectively. Thus, if the terminal A is connected to the terminal B and the terminal D is connected to the terminal E, the module signal line  200  is identical to the USB signal line. On the other hand, the terminals C and F are coupled with the connection terminal  10 , and correspond to T×D (transmission data line) and R x D (reception data line), respectively. Thus, if the terminal A is connected to the terminal C and the terminal D is connected to the terminal F, the module signal line  200  is identical to the asynchronous signal line. The in-module switch section  60  includes terminals G to L. The terminals H and K correspond to D+ and D− of the bi-directional signal line, respectively. The terminals I and L correspond to T×D (transmission data line) and R×D (reception data line), respectively.  
      An explanation will be given of the operation of the switch section  14  and in-module switch section  60  having the configurations described above. When a signal is transferred between the CPU  12  and the communication CPU  28 , in the switch section  14 , the terminals A and B are connected and the terminals D and E are connected, whereas in the in-module switch section  60 , the terminals G and H are connected and the terminals J and K are connected. Thus, the module signal line  200  serves as the USB signal line. On the other hand, when the signal is transferred between the connection terminal  10  and the communication CPU  28 , in the switch section  14 , the terminals A and C are connected and the terminals D and F are connected, whereas in the in-module switch section  60 , the terminals G and I are connected and the terminals J and L are connected. Thus, the module signal line  200  serves as the asynchronous serial signal line. In either case, the communication module  16  uses as an interface the module signal line  200  which includes four signal lines. Further, it is assumed that the module signal line  200  has a transfer speed varying according to the USB signal line or the asynchronous serial signal line. When the CPU  12  and the communication module  16  are connected or the connection terminal  10  and the communication module  16  are connected, the switch section  14  and in-module switch section  60  operate as described above, but this will not be explained in the following description.  
      The switch  18  has a function for the user to instruct the switching of the switch section  14  and the in-module switch section  60 . That is, to use the communication module  16  with the CPU  12 , the user operates the switch  18  so as to connect the communication module  16  and the CPU  1 . To use the communication module  16  with the external device  110  connected to the connection terminal  10  through the external device terminal  36 , the user operates the switch  18  so as to connect the communication module  16  and the connection terminal  10 .  
      The display section  22  mainly displays the processing result of the CPU  12 . It is a liquid crystal display, etc., by way of an example; it may be a main display or when the information processing device  100  is of folding type and has a sub-display, the display section  22  may be the sub-display. In the case that the connection terminal  10  and the communication module  16  are connected by the switch section  14  and the in-module switch section  60 , the CPU  12  determines the state of the switch section  14  and displays a message to the effect that the function of the communication module  16  cannot be used from the CPU  12 .  
      The operation section  24  is an interface for the user of the information processing device  100 , and includes a keyboard, buttons, etc. The operation section  24  need not be hardware and may be a software keyboard, etc., displayed in the display section  22 .  
      The notification section  26  is an LED, etc., controlled by the communication module  16 . The notification section  26  can notify the user of the operation of the communication module  16  even if the CPU  12  is in a non-operating state. The notification section  26  notifies the user of the operation state of the communication module  16 , such as operating/non-operating, communicating, or standby mode, blind spot, reception strength, etc., by color, on/off, blinking/non-blinking, blinking period, etc. With PCMCIA card type, etc., in a related art, an LED exists on the card, for example. However, if an LED is provided on the communication module  16  which is incorporated in the information processing device, the user cannot see the LED and thus the LED is provided on the cabinet of the information processing device  100  and is controlled from the communication module  16 . If the information processing device  100  is off, the LED can be used.  
      Further, in the cdmaOne, cdma2000 1x cellular phone communication terminal, the control lines connected to the connection terminal  10  include a voice input/output (analog, single end) signal line in the 18-conductor coupling connector. A voice input/output terminal of the communication module  16  and a voice input/output signal terminal of the connection terminal  10  are connected, whereby the connection terminal  10  can be used not only for use of an asynchronous serial signal to write subscriber information, etc., but also for use of voice input/output as a hands-free unit, etc.  
      The configuration can be implemented by a CPU, memory, and other LSIs of any desired computer as hardware and can be implemented by a program having a programming management function loaded into the memory, etc., as software. However, in the drawing, the configuration made up of the connection terminal  10 , the CPU  12 , the switch section  14 , the communication module  16 , etc., is drawn. Therefore, it will be obvious to those skilled in the art that the functional blocks can be implemented in various modes of hardware only, software only, or combination thereof.  
       FIGS. 2A and 2B  show the back and the face of the appearance of the information processing device  100 .  FIG. 2A  shows the back of the information processing device  100 . A lid  38 , a first mounting screw  40 , and a second mounting screw  42  are provided so as to cover the connection terminal  10 . In the case that the connection terminal  10  is used not for the edition of telephone directory by a user or the connection with a PC but only for the terminal maintenance by a common carrier to write subscriber information, etc., the connection terminal  10  provided on the back or a side of the information processing device  100  is covered with the lid  38  and is fixed by the first mounting screw  40  and the second mounting screw  42 . The first mounting screw  40  and the second mounting screw  42  are those similar to special screws used to prohibit the user from disassembling the device such as arrow-shaped or tamperproof-recess-shaped screws other than general plus or minus threads.  FIG. 2B  shows the face of the information processing device  100 . The display section  22 , the operation section  24 , and the notification section  26  are provided on the face. If the connection terminal  10  is unnecessary for the user, the described structure can prevent the user from accidentally connecting a PC, etc., to the connection terminal  10 . The configuration is not limited to the described structure and may be any if it prevents the user from accidentally connecting a PC, etc., to the connection terminal  10 .  
       FIG. 3  shows an example of display of the display section  22 . The display section  22  may produce display for enabling the user to recognize that the communication module  16  incorporated in the information processing device  100  cannot be used from the operation section  24 , such as text display of “communication function is switched to external terminal” or the like or any desired icon display.  
      According to the embodiment, the signal line to input the subscriber information is shared with a part of the signal line used for communications in the information processing device  100 , so that the area occupied by the signal line can be reduced. Further, since the transfer speed is varied according to the connecting format of the signal lines, the communication at a high transfer speed can be executed. Since the number of the terminals in the communication module  16  can be reduced, the circuit configuration can be simplified. Since the subscriber information input from the connection terminal  10  is not input to the CPU  12 , safety is also ensured from the viewpoints of security. When the subscriber information is written, a message to the effect that the subscriber information is written is displayed on the display section  22 , so that the user can easily recognize the operation. When the subscriber information is written, the notification section  26  notifies the user that the subscriber information is written, so that the user can easily recognize the operation even when the CPU  12  in the information processing device  100  is in halt.  
     Second Embodiment  
      A second embodiment of the invention relates to an information processing device incorporating a communication module like the first embodiment. The second embodiment differs from the first embodiment in the switching methods of switch section and in-module switch section. If a connection terminal of an external device is connected to a connection terminal of the information processing device, it is detected and the switch section and the in-module switch section connect a communication module and the connection terminal of the information processing device. On the other hand, if connection of a connection terminal of an external device and the connection terminal of the information processing device is not detected, the switch section and the in-module switch section connect the communication module and the CPU.  
       FIG. 4  shows the configuration of an information processing device  200  according to the second embodiment of the invention. A connection detection section  44  is added to the information processing device  200  in  FIG. 4  as compared with the information processing device  100  in  FIG. 1 . In the information processing device  200  in  FIG. 4 , parts not relating to the description of the second embodiment, such as the notification section  26  of the information processing device  100  in  FIG. 1 , are not shown. In fact, the parts may exist.  
      The connection detection section  44  detects the external device terminal  36  of the external device  110  (not shown in  FIG. 4 ) being inserted into the connection terminal  10 . The switch section  14  connects the communication module  16  and the connection terminal  10  if the external device terminal  36  of the external device  110  is inserted based on the detection result of the connection detection section  44 . Unless the external device terminal  36  of the external device  110  is inserted, the switch section  14  connects the communication module  16  and the CPU  12 . Further, in synchronization with the connection in the switch section  14 , the in-module switch section  60  (not shown) of the communication module  16  is connected as described above.  
      According to the embodiment, the switch section switches in association with connection of an external device  110 , so that the number of work steps of write processing of subscriber information is decreased and it is made possible to facilitate the work.  
     Third Embodiment  
      A third embodiment of the invention relates to an information processing device incorporating a communication module like the first embodiment. The third embodiment differs from the first embodiment in the switching methods of switch section and in-module switch section. An instruction terminal for accepting a subscriber information input instruction from an external device is provided in a connection terminal. To write subscriber information into the information processing device, the user operates an external device to transmit a subscriber information input instruction to the instruction terminal. Upon acceptance of the instruction, the switch section and the in-module switch section connect a communication module and the connection terminal. On the other hand, in a usual state, the switch section and the in-module switch section connect the communication module and a CPU.  
       FIG. 5  shows the configuration of an information processing device  300  according to the third embodiment of the invention. A control signal line  46  is added to the information processing device  300  in  FIG. 5  as compared with the information processing device  100  in  FIG. 1 .  
      The control signal line  46  is a part of a signal line connected to a connection terminal  10  and is a control line for transmitting an instruction to write subscriber information into a communication module  16 . The control signal line  46  is connected from the connection terminal  10  to the communication module  16 . The communication module  16  of EV-DO system or cdma2000 1x system is controlled by two control signals  1  and  2 , which are previously defined, in an 18-conductor coupling connector. The operation of the communication module  16  such as power forcible on, forcible off, or non-control is determined according to the state of the two control signals. Since power of the communication module  16  is turned on or off in response to the state of the control signal line  46 , the external device  110  (not shown in  FIG. 5 ) can control the operation of the communication module  16  via the control signal line  46  from the external device  110  regardless of whether or not the main unit of the information processing device  300  operates. For example, when the communication module  16  detects the instruction to write subscriber information transmitted through the connection terminal  10 , the switch section  14  switches the connection of the communication module  16  to the connection terminal  10 .  
      According to the embodiment, the switch section  14  and the in-module switch section  60  can switch from an external device  110 , so that switch processing can be facilitated.  
     Fourth Embodiment  
      A fourth embodiment of the invention relates to an information processing device incorporating a communication module like the first embodiment. In the fourth embodiment, if a switch section and an in-module switch section connect a communication module and a connection terminal by the method shown in the embodiments descried above, it is detected and power of a CPU is turned off. That is, power of only the parts required for write processing centering on the communication module is turned on during execution of subscriber information write processing by an external device.  
       FIG. 6  shows the configuration of an information processing device  400  according to the fourth embodiment of the invention. A connection detection section  44 , a communication power control section  48 , an information processing device power control section  50 , and a battery  52  are added to the information processing device  400  in  FIG. 6  as compared with the information processing device  100  in  FIG. 1 .  
      The communication power control section  48  and the information processing device power control section  50  receive power supply from the battery  52  and control the power of a communication module  16  and a CPU  12 . The communication module  16  incorporated in the information processing device  400  receives power supply from the battery  52  incorporated in the information processing device  400 , and the communication power control section  48  and a communication CPU  28  in the communication module  16  control the power of the communication module  16 . Similarly, the main unit of the information processing device  400  receives power supply from the battery  52 , and the information processing device power control section  50  and the CPU  12  in the information processing device  400  control the power and the operation. The information processing device power control section  50  is controlled by the. CPU  12  and supplies the power to the CPU  12  and a display section  22 .  
      For the information processing device  400  to conduct communications using the communication module  16 , the communication power control section  48  of the communication module  16  supplies the power to the sections in the communication module  16  including the communication CPU  28 , and the information processing device power control section  50  supplies the power to the CPU  12  and the display section  22 , placing the main unit of the information processing device  400  and the communication module  16  in an operation state with the power supplied. On the other hand, to save power consumption of the battery  52 , when the communication module  16  and the main unit of the information processing device  400  need not operate, power supply is controlled individually according to the decision of the communication CPU  28  in the communication module  16  and the CPU  12 , and the operation is stopped or the current consumption is decreased in such a manner that power supply to an unnecessary part or the whole power supply is stopped.  
      More particularly, output of the connection detection section  44  controls switching of a switch section  14  and an in-module switch section  60  (not shown), and at the same time, is input to the CPU  12 . The CPU  12  then determines the state of a connection terminal  10  based on the output of the connection detection section  44 . When the external device terminal  36  from the external device  110  (not shown in  FIG. 6 ) is inserted, namely, the communication module  16  and the connection terminal  10  are connected and the communication module  16  is directly controlled from the external device  110 , the function of the main unit of the information processing device  400  is not required. Therefore, the information processing device power control section  50  is controlled for switching the main unit of the information processing device  400  into a current consumption decrease mode such as power off, sleep state, or power saving mode. Accordingly, when the external device  110  uses the communication module  16 , unnecessary power consumption of the main unit of the information processing device  400  can be decreased.  
      The operation state to decrease the power consumption in the communication module  16  may include a complete function stop state in which power supply to the communication CPU  28  is stopped or an intermittent standby state in which the machine is started about once every several seconds with a timer and a radio reception state is monitored and if the home station is not called, other parts than the timer are placed in a sleep mode for decreasing average current consumption. The operation state to decrease the power consumption in the main unit of the information processing device  400  may include a complete function stop state in which power supply to the parts is stopped, a sleep state in which power is supplied only to the display section  22 , a power saving mode in which the operation clock of the CPU  12 , etc., is lowered for lessening the power consumption although power is supplied to the parts, or the like.  
      According to the embodiment, the power of the CPU  12  can be turned off to perform write processing of the subscriber information, so that low power consumption is made possible.  
     Fifth Embodiment  
      A fifth embodiment of the invention relates to an information processing device incorporating a communication module like the first embodiment. The fifth embodiment differs from the first embodiment in the switching methods of switch section and in-module switch section. If power of a CPU is turned off, it is detected and the switch section and the in-module switch section connect a communication module and a connection terminal. On the other hand, in a usual state, the switch section connects the communication module and the CPU. The relationship between turning on or off power of the CPU and the switch timing of the switch section and the in-module switch section is opposite as compared with the fourth embodiment.  
       FIG. 7  shows the configuration of an information processing device  500  according to the fifth embodiment of the invention. A power switch  54  is added to the information processing device  500  in  FIG. 7  as compared with the information processing device  100  in  FIG. 1 .  
      The power switch  54  is a switch of the main unit of the information processing device  500 . In the embodiment, a switch section  14  and the in-module switch section  60  (not shown) are switched in association with the power switch  54 . When power of the information processing device  500  is on, the switch section  14  switches to connect a communication module  16  and a CPU  12 . When power of the information processing device  500  or the CPU  12  is off, the switch section  14  switches to connect the communication module  16  and a connection terminal  10 . Accordingly, when the information processing device  500  is in a non-operating state, namely, when the communication module  16  and the CPU  12  need not conduct communications and an external device  110  (not shown in  FIG. 7 ) uses the communication module  16 , the communication module  16  can be used via the connection terminal  10  without any switch operation, etc by the user.  
      According to the embodiment, the power of the CPU  12  can be turned off to perform write processing of the subscriber information, so that low power consumption is made possible.  
      The invention has been described based on the embodiments. It is understood by those skilled in the art that the embodiments are illustrative and that various changes and modifications may be made in the invention without departing from the spirit and scope thereof.  
      In the first embodiment, the switch section  14  and the in-module switch section  60  are switched as the switch  18  is switched. However, the invention is not limited to it. For example, the switch section  14  may be switched based on user&#39;s operation for the CPU  12  through the operation section  24  or condition decision in the CPU  12 . For example, if the user operates the operation section  24  so that the CPU  12  does not use the communication module  16 , the switch section  14  switches to connect the communication module  16  and the connection terminal  10 . If the user operates the operation section  24  so that the CPU  12  uses the communication module  16 , the switch section  14  switches to connect the communication module  16  and the CPU  12 . According to the modification, the switch  18  becomes unnecessary and the information processing device  100  can be furthermore miniaturized.  
      In the fifth embodiment, the switch section  14  and the in-module switch section  60  are switched as the power switch  54  is switched. However, the invention is not limited to it. For example, in the configuration in which turning on/off the power of the main unit of the information processing device  100 , etc., is controlled through the operation section  24  in  FIG. 1 , when the user turns off the information processing device  100  through the operation section  24  or the CPU  12  autonomously causes the information processing device  100  to make a transition to a non-operating state, the switch section  14  and the in-module switch section  60  may connect the connection terminal  10  and the communication module  16  before the power is turned off. According to the modification, the power switch  54  becomes unnecessary and the information processing device  100  can be furthermore miniaturized.  
      In the first to fifth embodiments, the information processing devices  100  to  500  are for example PDA, but may be any other than PDA and may be PC. According to the modification, the invention can be applied to various information processing devices. That is, the information processing device may be any if it can process digitalized information.  
      The first embodiment can also be combined with any of the second to fifth embodiments. According to the combination, as the switch section  14  and the in-module switch section  60  switch, a predetermined message is displayed on the display section  22  and the notification section  26  provides the user with predetermined information in the second to fifth embodiments.  
      The fourth embodiment can also be combined with the second embodiment. According to the combination, the power of the CPU  12  is turned off in response to the state of the control signal line  46 .