Patent Publication Number: US-2006014567-A1

Title: Data communication system, connector cable and communication adapter medium used in the data communication system

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The invention relates to a data communication system, particularly to data communication system for effecting data communication between a portable device and a computer, and a connector cable and communication adapter medium used in the data communication system.  
      This application is a counterpart of Japanese patent application Serial Number 28778/2001, filed Sep. 18, 2001, the subject matter of which is incorporated herein by reference.  
      2. Description of the Related Art  
      A mobile radiophone has become recently widely used remarkably in Japan, and telecommunications companies employ their own communication systems while a standardized communication system has not been employed. For a digital cellular phone, there are communication systems such as a PDC (Personal Digital Cellular) system, cdmaOne system and the like. For a PHS (Personal Handyphone System), there are communication systems such as a guarantee system, a best effort system and the like. The PDC system used here is a TDMA (Time Division Multiple Access) system which is standardized in Japan. Meanwhile, the cdmaOne system is a radio communication system complying with an international standard and is characterized in a high data transmission speed compared with the PDC system. The guarantee system in the PHS complies with a PIAFS (PHS Internet Access Forum Standard) v2.0 to use a fixed transmission speed while the best effort system in the PHS complies with PIAFS v2.1 to use a valuable transmission speed.  
       FIG. 5  is a table showing an outline of communication protocols, a hardware specification, and an dedicated connector in the PDC system, the guarantee and best effort systems in the PHS as examples of the communication systems. The dedicated connector is varied in the number of the pin in response to the difference in hardware specification, differentiated in shape, and common or not common in signal line, which are inherent in the respective communication systems.  
      Accordingly, when a user effects data communication with respect to an external device such as the Internet using a computer such as a mobile computer while using these cellular phones as radio terminals, the user has to purchase an independent or separate data communication adapter to be suited for the cellular phone so as to be connected thereto, so that an inconvenience is given to the user. Meanwhile, manufacturers manufacturing these data communication adapters have to supply data communication adapters to a client which adapters are differentiated corresponding to cellular phones of respective telephone companies.  
     SUMMARY OF THE INVENTION  
      One of typical data communication systems of the invention comprises a portable device for effecting a radio communication, a communication adapter card for storing therein a plurality of communication protocols corresponding to respective multiple communication systems employed by the portable device, a computer in which the communication adapter card is inserted to execute data processing, a first connector connected to the portable device, a second connector connected the first connector and the communication adapter card to identify one of the communication systems employed by the portable device and a connector cable formed of a cable for connecting the first and second connectors.  
      Accordingly, it is an object of the invention to provide a data communication system capable of effecting data communication between portable devices having different communication systems and a computer.  
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  shows an entire data communication system according to the invention;  
       FIG. 2  is a view showing the construction of a connector cable according to a first embodiment of the invention used in the data communication system;  
       FIG. 3  is a view showing the construction of a connector cable according to a second embodiment of the invention used in the data communication system;  
       FIG. 4  is a block diagram showing the construction of a communication adapter card used in the data communication system according to a third embodiment of the invention.; and  
       FIG. 5  is a table showing communication systems of a mobile radiophone. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       FIG. 1  shows an entire data communication system according to the invention. The data communication system of the invention comprises a portable device  110 , a connector cable  120 , a communication adapter card  130  and a computer  140 . The portable device  110  is one of a variety of portable devices employing various communication systems, and effects radio communication. For the portable device  110 , there are, e.g. a cellular phone, a PHS telephone or a communication terminal capable of effecting mobile communication. The connector cable  120  comprises a connector (first connector)  121 , a connector (second connector)  122  and a cable  123  comprised of a plurality of conducting wires. The cable  123  connects between the connectors  121  and  122 . The communication adapter card  130  is a card for effecting data communication corresponding to a communication system of the portable device  110 . The hardware specification and software specification of the communication adapter card  130  are complying with the standard of a PCMCIA (Personal Computer Memory Card International Association). The computer  140  has a slot  140 A.  
      The portable device  110  is connected to the computer  140  by way of the connector cable  120  and the communication adapter card  130  and effects data communication between itself and the computer  140 . The portable device  110  is connected to the connector  121  of the connector cable  120 . The connector  122  of the connector cable  120  is connected to the communication adapter card  130 . The communication adapter card  130  is inserted into the slot  140 A of the computer  140 .  
      The connector cable  120  used in the data communication system according to the first embodiment of the invention is first described.  FIG. 2  is a view showing the construction of the connector cable according to the first embodiment of the invention. The connector cable  120  comprises the connector (first connector)  121 , the connector (second connector)  122 , and the cable  123  as set forth above. The connector  122  identifies a communication system employed by the portable device  110  and has an identification part for outputting identification information. The identification part comprises a switch SW 1  and a switch SW 2 . The connector  122  has a side surface  122 A and a front surface  122 B. A connection terminal  200  to be connected to the communication adapter card  130  is provided on the front surface  122 B of the connector  122 . The connection terminal  200  comprises a plurality of terminals arranged in two rows. Two identification terminals  210 ,  220  provided on the uppermost position of the connection terminal  200  output identification information representing a communication system employed by the portable device  110 . The two identification terminals may be provided at the lowermost position of the connection terminal  200 . The identification terminal  210  is connected to the identification part. More in detail, the identification terminal  210  is connected to the switch SW 1  provided inside the connector  122  while the identification terminal  220  is connected to the switch SW 2  provided to the inside the connector  122 . Other ends of the switches SW 1 , SW 2  are connected to either a power supply (VCC) terminal or ground (GND) terminal. That is, there are four combinations for outputting outputs (2-bit outputs) of two identification terminals. As a result, if a 2/bit identifier is given to each communication system, it is possible to identify up to four communication systems. Although four combinations can be prepared by 2-bit outputs, it is needless to say that sixteen combinations may be prepared by 4-bit outputs.  
      The connector cable used in the data communication system according to a second embodiment of the invention is described next.  FIG. 3  is a view showing the construction of the connector cable according to the second embodiment of the invention. A connector cable  120  of the second embodiment comprises a connector  121 , a connector  300 , and a cable  123 . The connector  300  of the connector cable  120  has a side surface  300 A and a front surface  300 B. A switching part which can be manually switched is provided on the side surface  300 A of the connector  300  in response to a communication system employed by a portable device  110 . The switching part comprises two dip switches  310 . A connection terminal  320  to be connected to a communication adapter card  130  is provided on the front surface  300 B of the connector  300 . The connection terminal  320  comprises a plurality of terminals arranged in two rows. The connection terminal  200  has two identification terminals. The two identification terminals output identification information representing a communication system employed by the portable device  110 .  
      The two dip switches  310  and two identification terminals are electrically connected to each other. Two identification terminals can output four combinations of 2-bit outputs when the two dip switches  310  are manually switched. As a result, if a 2/bit identifier is given to each communication system, it is possible to identify up to four communication systems. Accordingly, when a user of the portable device  110  manually switches two dip switches  310  in response to a communication system of the portable device  110 , the user can select an optimum communication system from an external device.  
      A communication adapter card used in the data communication system according to a third embodiment of the invention is described next.  FIG. 4  is a block diagram showing the construction of the communication adapter card according to the third embodiment of the invention.  
      A communication adapter card  130  comprises a connection terminal  410 , a PCMCIA terminal  420 , a system decision circuit  430 , an internal bus  440 , a communication system switching circuit  450 , a card bus interface  460 , a CPU  470 , and a memory  480 . The connection terminal  410  is connected to connection terminals  200 ,  320  of a connector cable  120 . The system decision circuit  430  is connected to the connection terminal  410  and the communication system switching circuit  450 . The communication system switching circuit  450 , the card bus interface  460 , the CPU  470  and the memory  480  are respectively connected to the internal bus  440 . The card bus interface  460  is connected to the PCMCIA terminal  420 . The PCMCIA terminal  420  is electrically connected to a computer  140  when the communication adapter card  130  is inserted into a slot  140 A of the computer  140 .  
      The system decision circuit  430  is electrically connected to identification terminals of the connection terminals  200 ,  320  of the connector cable  120 . The system decision circuit  430  fetches therein identification signals of the communication systems outputted from the identification terminals of the connection terminals  200 ,  320  as electric signals. The system decision circuit  430  discriminates a communication system employed by the portable device  110  on the basis of the identification signals, and outputs the result of discrimination.  
      The communication system switching circuit  450  comprises a protocol selection circuit  451 , a status register  452 , individual circuits  453 ,  454 ,  455 , a common circuit  456 , and a multiplexer  457 . The protocol selection circuit  451 , the status register  452 , the individual circuits  453 ,  454 ,  455 , and the common circuit  456  are respectively connected to one another by way of the internal bus  440 . The protocol selection circuit  451 , the individual circuits  453 ,  454 ,  455 , and the common circuit  456  are respectively connected to the multiplexer  457 . The protocol selection circuit  451  fetches therein the result of discrimination outputted from the system decision circuit  430  and selects one of detailed communication protocols as shown the table of  FIG. 5 . The protocol selection circuit  451  sets the selected communication protocol at the status register  452 . Each of the individual circuits  453 ,  454 ,  455  has a protocol engine for executing each communication procedure corresponding to a plurality of communication protocols. The common circuit  456  executes processing which is common to each communication procedure. The multiplexer  457  properly switches the individual circuit  453 , the individual circuit  454 , the individual circuit  455  and the common circuit  456 , and outputs a communication data in multiplex manner or separately based on a control signal outputted from the protocol selection circuit  451 . Both the system decision circuit  430  and the communication system switching circuit  450  are realized by an dedicated LSI, thereby achieving low power consumption and miniaturization.  
      The card bus interface  460  effects communication of data and control signals with respect to the computer  140  by way of the PCMCIA terminal  420  based on an interface complying with the PCMCIA standard. The CPU  470  is a processor for controlling the entire processing of the communication adapter card  130 , and it executes the processing in corporation with the memory  480 . The communication is executed by the memory  480  under the control of the CPU  470  even if the communication is executed based on any communication protocol. The CPU  470  decides a communication protocol which is selected from information written in the status register  452  and controls to send and receive the communication data in accordance with the communication protocol. The card bus interface  460 , the CPU  470  and the memory  480  use a general purpose LSI.  
      The first to third embodiments of the invention are structured to select one of three communication systems, namely, the PDC system in the cellular phone, the guarantee and best effort systems in the PHS. However, it is needless to say that a communication system other than these three communication systems can be employed. Further, although the communication adapter is formed of the PC card according to the embodiments, it may be formed of an adapter in the form of a USB (universal serial bus) system. Still further, although the switches are provided on the connector cable for identifying the communication systems, they may be provided on the communication adapter card.