Abstract:
A radio paging receiver with a display unit which includes a character generator, display section, and display control unit for reading characte patterns corresponding to constituent elements of a message contained in a paging signal from said character generator, controlling the display section on the basis of the read character patterns, and displaying the message on the display section, wherein the display control unit includes a function of displaying constituent elements of messages having different sizes on the display section.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    1. Field of the Invention  
           [0002]    The present invention relates to a radio paging receiver with a display unit having a function of displaying a received message on a screen.  
           [0003]    2. Description of the Prior Art  
           [0004]    In recent years, innovative technical developments have been remarkably made for radio paging receivers. In place of a tone-only type radio paging receiver having only a function of notifying a user of being paged by sounds a radio paging receiver with a display unit having a function of displaying a message on a screen has been popularly used.  
           [0005]    In a prior art radio paging receiver of this type with a display unit, characters and numbers in a received message are displayed on the display unit in a predetermined size. When a message cannot be displayed on one screen because the size of the message is large, the screen is switched by a user, the message is continuously displayed on a plurality of screens.  
           [0006]    [0006]FIG. 1 is a view showing a liquid crystal display section  171  in an example of the prior art radio paging receiver having a message display function.  
           [0007]    As shown in FIG. 1, the liquid crystal display section  171  has a message display portion  172  for displaying a message, and the message display portion  172  is divided into a plurality of unit regions  173  each having a predetermined size (dot count). Each of the unit regions  173  is a region in which a unit display component such as one character or one number is displayed.  
           [0008]    When a conventional radio paging receiver having the above liquid crystal display section  171  receives a self-paging signal containing a message, each unit display component such as one character or one number is displayed on a corresponding one of the unit regions  173 . When the message cannot be displayed on one screen because the number of characters in the message is large, a screen switching operation is performed by a user, and the message is continuously displayed on a plurality of screens.  
           [0009]    As described above, in the conventional radio paging receiver having the display unit, the message display portion for displaying a message is divided into unit regions each having a predetermined dot count, and each unit display component is displayed on a corresponding one of the unit regions. For this reason, the following problem is posed.  
           [0010]    That is, when the message display portion is divided into a large number of unit regions, the number of characters which can be displayed on one screen is increased. For this reason, when a long message is to be displayed, the number of screen switching operations is decreased. However, since the dot count in each unit region is decreased, even when a short message is to be displayed, characters and the like are displayed in a small size, and the displayed message cannot be easily read.  
           [0011]    When a message display portion is divided into a small number of regions, the dot count in each unit display element is increased, and the displayed message can be easily read. However, when a long message is received, a screen switching operation must be disadvantageously performed many times.  
         SUMMARY OF THE INVENTION  
         [0012]    It is an object of the present invention to provide a radio paging receiver with a display unit, in which the size of each character displayed on a message display portion is changed in accordance with the length of a message to be displayed, so that the number of screen switching operations can be decreased when a long message is displayed, and characters and the like which can be easily read can be displayed when a short message is displayed.  
           [0013]    In order to achieve the above object, according to the first aspect of the present invention, there is provided a radio paging receiver with a display unit which includes a character generator, a display section, and display control means for reading character patterns corresponding to constituent elements of a message contained in a paging signal from the character generator, controlling the display section on the basis of the read character patterns, and displaying the message on the display section, wherein the display control means includes a function of displaying constituent elements of messages having different sizes on the display section.  
           [0014]    According to the second aspect of the present invention, there is provided a radio paging receiver with a display unit of the first aspect, further comprising a counter for counting the number of character patterns read from the character generator, and wherein the display control means displays constituent elements of a message on the display section in a size depending on a character pattern count value obtained by the counter.  
           [0015]    According to the third aspect of the present invention, in the radio paging receiver with a display unit according to any one of the first and second aspects, the character patterns are dot patterns, and the constituent elements of a message on the display section are constituted by dot display elements.  
           [0016]    According to the present invention, the constituent elements of a message contained in a paging signal are constituted by dot display elements, the number of display elements is counted by the counter, and the constituent elements (unit display component) such as characters and numbers of the message are displayed on the display section in a size depending on the resultant value obtained from the counter. Therefore, when a long message is received, the constituent elements of the long message can be displayed on the display section in a small size; and when a short message is received, the constituent elements of the short message can be displayed on the display section in a large size.  
           [0017]    As described above, according to the present invention, when a long message is received, the number of screen switching operations can be advantageously decreased; when a short message is received, the message can be displayed to be easily read.  
           [0018]    The above and many other advantages, features and additional objects of the present invention will become manifest to those versed in the art upon making reference to the following detailed description and accompanying drawings in which preferred structural embodiments incorporating the principles of the present invention are shown by way of illustrative example. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0019]    [0019]FIG. 1 is a schematic plan view showing the arrangement of a liquid crystal display section of a prior art radio paging receiver with a display unit;  
         [0020]    [0020]FIG. 2 is a schematic plan view showing the arrangement of a liquid crystal display section according to an embodiment of the present invention;  
         [0021]    [0021]FIG. 3 is a block diagram showing the arrangement of the first embodiment of the present invention;  
         [0022]    [0022]FIG. 4 is a flow-chart showing processing of a decoder used in the first embodiment;  
         [0023]    [0023]FIG. 5 is a flow-chart showing processing of a control section used in the first embodiment;  
         [0024]    [0024]FIG. 6 is a flow-chart as a continuation of the flow chart shown in FIG. 5;  
         [0025]    [0025]FIG. 7 is a timing-chart showing an operation of the first embodiment;  
         [0026]    [0026]FIG. 8 is a view for explaining a display sample obtained when a short message is received in the first embodiment;  
         [0027]    [0027]FIG. 9 is a view for explaining a display sample obtained when a long message is received in the first embodiment;  
         [0028]    [0028]FIG. 10 is a timing-chart showing an operation of the first embodiment when a short message is received;  
         [0029]    [0029]FIG. 11 is a timing-chart showing an operation of the first embodiment when a long message is received;  
         [0030]    [0030]FIG. 12 is a format for explaining a paging signal sent when a character of 2N×2M dots is displayed;  
         [0031]    [0031]FIG. 13 is a format for explaining a paging signal sent when a character of N×M dots is displayed;  
         [0032]    [0032]FIG. 14 is a block diagram showing the second embodiment of the present invention;  
         [0033]    [0033]FIG. 15 is a flow-chart showing processing of a control section used in the second embodiment;  
         [0034]    FIGS.  16  to  18  are flow-charts as continuations of to the flow chart showing in FIG. 15;  
         [0035]    [0035]FIG. 19 is a plan view showing a liquid crystal display section serving as a waiting screen;  
         [0036]    [0036]FIG. 20 is a view for explaining a display sample of the liquid crystal display section when no message is received;  
         [0037]    FIGS.  21  to  23 ,  24 A, and  24 B are views showing display samples of the liquid crystal display section when the dot count of each unit display component is changed in accordance with the number of characters of a message; and  
         [0038]    [0038]FIGS. 25, 26A, and  26 B are views for explaining display samples of the liquid crystal display section when the dot count of each unit display component is fixed.  
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0039]    The present invention will be described in more detail below with reference to the preferred embodiments shown in the accompanying drawings.  
         [0040]    [0040]FIG. 2 is a schematic plan view showing the arrangement of a liquid crystal display section  17  in an embodiment of the present invention, and the liquid crystal display section  17  is constituted by a message display portion  21 , a symbol display portion  22 , and a time and date display portion  23 .  
         [0041]    The message display portion  21  is constituted by dot display elements and displays a message.  
         [0042]    An off-boundary detection mark  24 , a received address display mark  25 , a received function display mark  26 , a low-voltage display mark  27 , a switch position display mark  28 , an identical paging display mark  29 , a message protection mark  30 , and a next screen message continuous mark  31  are displayed on the symbol display portion  22 .  
         [0043]    A message reception order  32 , time  33 , and date  34  are displayed on the time and date display section  23 . FIG. 3 is a block diagram showing the arrangement of the first embodiment of the present invention, and a radio paging receiver according to the first embodiment is constituted by an antenna  1 , a radio section  2 , a waveform shaping circuit  3 , a decoder  4 , an ID-ROM  5 , an oscillator  6 , a power supply  7 , a loudspeaker driving section  8 , a loudspeaker  9 , an LED driving section  10 , a light-emitting diode  11 , a memory  12 , a control section  13 , a character generator (CG-ROM)  14 , a counter  15 , a display driving section  16 , a display section  17 , and a pulse generator  18 .  
         [0044]    [0044]FIG. 4 is a flow chart showing processing of the decoder  4 , and FIGS. 5 and 6 are flow charts showing processing of the control section  13 . An operation of this embodiment will be described below with reference to FIGS. 4, 5, and  6 .  
         [0045]    A paging signal received by the antenna  1  is amplified and demodulated by the radio section  2 , and then converted into a signal, which can be read by the decoder  4 , in the waveform shaping circuit  3 .  
         [0046]    When the decoder  4  receives the paging signal having the waveform shaped by the waveform shaping circuit  3 , as shown in FIG. 4, a paging number contained in the signal is collated with a self-paging number stored in the ID-ROM  5  (step S 1 ).  
         [0047]    When the numbers do not coincide with each other (NO in step S 1 ), the decoder  4  waits for a next paging signal. When the numbers coincide with each other (YES in step S 1 ), it is checked whether a message following the paging number is present (step S 2 ).  
         [0048]    When it is determined in step S 2  that a message is not present (NO in step S 2 ), a drive signal is supplied to the loudspeaker driving section  8  and the LED driving section  10  to drive the loudspeaker  9  and the light-emitting diode  11  so as to notify a user of being paged (step S 3 ).  
         [0049]    The decoder  4  starts a T-second timer (step S 4 ). When the timer is turned off, or a reset switch (not shown) is depressed by the user, the operations of the loudspeaker  9  and the light-emitting diode  11  are ended (steps S 5  to S 7 ).  
         [0050]    When it is determined in step S 2  that a message is present (YES in step S 2 ), the decoder  4  stores the message in the memory  12  (step S 8 ). When all messages are stored in the memory  12  (YES in step S 9 ), the control section  13  is started (step S 10 ).  
         [0051]    Thereafter, the decoder  4  supplies a drive signal to the loudspeaker driving section  8  and the LED driving section  10  to drive the loudspeaker  9  and the light-emitting diode  11  so as to notify the user of being paged (step S 11 ). When the user depresses the reset switch in response to the notifying operation (YES in step S 12 ), the decoder  4  ends the operations of the loudspeaker  9  and the light-emitting diode  11  (step S 13 ).  
         [0052]    When the control section  13  is started by the decoder  4 , as shown in the flow chart of FIG. 5, a count value A is set to be “0” first (step S 21 ). Thereafter, the control section  13  reads out one character of a message stored in the memory  12 , and a character pattern (2N×2M dot pattern; the pattern has a size to display sixteen patterns on the display section  17  as shown in FIG. 8) corresponding to the read character is read out from the character generator  14  (step S 22 ). The control section  13  repetitively performs the above processing until YES in step S 25 , i.e., until character patterns corresponding to all the characters of each message stored in the memory  12  are completely read out from the character generator  14 .  
         [0053]    The character patterns read out from the character generator  14  are supplied to the display driving section  16  and the pulse generator  18 . The display driving section  16  holds the character patterns from the character generator  14 , and the pulse generator  18 , as shown in FIG. 7, outputs a pulse every time a character pattern of one character is output from the character generator  14 . The number of pulses output from the pulse generator  18  is counted by the counter  15 , and the counter  15  outputs a pulse to the control section  13  every time sixteen pulses from the pulse generator  18  are counted.  
         [0054]    When the control section  13  receives a pulse from the counter  15  while reading character patterns from the character generator  14 , a counter value A is incremented by one (steps S 23  and S 24 ).  
         [0055]    When character patterns corresponding to all characters of each message stored in the memory  12  are read from the character generator  14  (YES in step S 25 ), the control section  13  checks whether the count value “A” is set to be “0”, i.e., whether the length of the message has less than sixteen characters (step S 26 ).  
         [0056]    When it is determined that the length of the message has less than sixteen characters (YES in step S 26 ), the control section  13  immediately outputs a display start signal to the display driving section  16  (step S 27 ). Otherwise (NO in step S 26 ), the control section  13  outputs a character size change designation signal to the display driving section  16  (step S 32 ), and then outputs a display start signal to the display driving section  16  (step S 33 ).  
         [0057]    When the display driving section  16  receives the display start signal without receiving the character size change designation signal (YES in step S 26 ), a segment signal is formed in accordance with character patterns (character patterns each having 2N×2M dots) corresponding to the message stored in the memory  12 , the resultant segment signal is output to the display section  17 , and the message is displayed on the display section  17 . FIG. 8 is a view showing a display sample obtained in this case.  
         [0058]    When the display driving section  16  receives the display start signal after the display driving section  16  receives the character size change designation signal (NO in step S 26 ), a segment signal is formed in accordance with character patterns each having N×M dots and each formed by thinning, e.g., even-numbered columns and even-numbered rows, from a corresponding one of the character patterns corresponding to the stored message. The resultant segment signal is output to the display section  17  to display the message on the display section  17 . FIG. 9 is a view showing a display sample obtained in this case. Since a display operation is performed in accordance with the segment signal formed on the basis of character patterns each having N×M dots, the size of each character is ¼ that of the message display portion in FIG. 8, and the number of characters which can be displayed on the message display portion in FIG. 9 is four times that on the message display portion in FIG. 8, i.e., sixty-four characters can be displayed on the display portion in FIG. 9.  
         [0059]    When the control section  13  outputs the display start signal in step S 27 , a T-second timer is started (step S 28 ). When the timer is turned off, or an operator depresses a display switch (not shown), the control section  13  instructs the display driving section  16  to turn off the display so as to end the display of the message (steps S 29  to S 31 ).  
         [0060]    When the display start signal is output in step S 33 , the control section  13  checks whether the count value “A” satisfies A&lt;4, i.e., whether the length of a message has less than sixty-four characters (step S 34 ).  
         [0061]    When it is determined that the number of characters of the message is smaller than sixty-four (YES in step S 34 ), processing in step S 28  is performed. When the number is not smaller than sixty-four, i.e., when a next screen is present (NO in step  34 ), after “4” is subtracted from the count value (step S 35 ), the control section  13  waits for depression of a next screen switch (not shown) (step S 36 ).  
         [0062]    When the next screen switch is depressed, the control section  13  outputs a next screen display signal to the display driving section  16  (step S 37 ), and the control section  13  checks whether the count value “A” satisfies A&lt;4, i.e., whether a next screen is present, (step S 38 ). When it is determined that the next screen is not present (YES in step S 38 ), processing in step S 28  is performed. When it is determined that the next screen is present (NO in step S 38 ), processing in step S 35  is performed again.  
         [0063]    When the display driving section  16  receives the next screen display signal, the display driving section  16  forms a segment signal for displaying a message (which is to be displayed) on the display section  17  by characters each having a size of N×M dots. The resultant segment signal is supplied to the display section  17  to display the message (which is to be displayed) on the display section  17  using characters each having N×M dots.  
         [0064]    [0064]FIG. 10 is a timing chart showing an operation performed when the length of a message has less than sixteen characters, and FIG. 11 is a timing chart showing an operation performed when the length of a message has sixteen or more characters.  
         [0065]    A pulse is output from the pulse generator  18  every time a character pattern of one character is output from the character generator  14 . When the length of a message has less than sixteen characters, since no pulse is output from the counter  15 , no character size change designation signal is output from the control section  13  to the display driving section  16 , as shown in FIG. 10. As a result, the message is displayed by characters each having 2N×2M dots.  
         [0066]    In contrast to this, when the length of a message has sixteen or more characters, as shown in FIG. 11, a pulse is output from the counter  15  when sixteen pulses are output from the pulse generator  18 . As a result, when the number of characters of the message is sixteen or more, a character size change designation signal is output from the control section  13  to the display driving section  16 , and the message is displayed by characters each having N×M dots.  
         [0067]    In the above-described embodiment, the length of a message is determined on the basis of the number of character patterns read from the character generator  14 , and a switching operation between display of a message using characters each having 2N×2M dots and display of a message using characters each having N×M dots is performed on the basis of the determination result. In addition, a character size switch which can be operated by a user may be arranged on the radio paging receiver with a display unit, so that the size of each character to be displayed may be switched in accordance with the state of this switch.  
         [0068]    When messages are to be displayed by characters eachhaving 2N×2M dots, as shown in FIG. 12, a paging signal constituted by a paging number ID and messages M 1  to M 6  is sent. When messages are to be displayed by characters each having N×M dots, as shown in FIG. 13, a paging signal constituted by a paging number ID, a control signal CS, messages M 1  to M 5  is sent. In this manner, a switching operation between display of the messages using characters each having 2N×2M dots and display of messages using characters each having N×M dots can be performed depending on the presence/absence of the control signal CS in a radio paging receiver with a display unit.  
         [0069]    In the above embodiment, although a pulse is output from the pulse generator  18  every time a character pattern of one character is output from the character generator  14 , a pulse can be output from the pulse generator  18  every time the control section  13  reads one character of a message from the memory  12 .  
         [0070]    Subsequently, the second embodiment of the present invention will be described with reference to FIGS.  14  to  26 B. FIG. 14 is a block diagram showing the arrangement of the second embodiment of the present invention. A receiver according to the second embodiment is constituted by an antenna  101 , a radio section  102 , a decoder  103 , a light-emitting diode  110 , a loudspeaker  111 , a driver  104  for driving a vibrator  112 , an ID-ROM  105 , a CPU  106 , a display driver  107  for driving a liquid crystal display section  108 , a character generator  109 , a power supply  113 , a power supply circuit  114 , and switches  115 . The switches  115  include a power supply switch, a notifying means driving switch for designating whether the light-emitting diode  110 , the loudspeaker  111 , and the vibrator  112  are driven, a dot count change switch for designating whether the dot count of a display unit to be displayed on the liquid crystal display section  108  is changed in accordance with the number of characters of a message, a next screen display switch for designating that a displayed screen is changed into a next screen, and a display erasing switch depressed when a message displayed on the liquid crystal display section  108  is to be erased. Display data of three sizes for each character are stored in the character generator  109 .  
         [0071]    FIGS.  15  to  18  are flow charts showing processing of the radio paging receiver with a display unit shown in FIG. 14, and an operation of the second embodiment will be described below.  
         [0072]    The radio paging receiver with a display unit shown in FIG. 14 is set in a waiting state by turning on the power switch of the switches  115  so as to display a waiting screen shown in FIG. 19 on the liquid crystal display section  108  (step S 1 ). On this waiting screen, as shown in FIG. 19, current time and date are displayed.  
         [0073]    The radio section  102  amplifies and demodulates a paging signal containing a message and received through the antenna  101  to supply the demodulated signal to the decoder  103 .  
         [0074]    When the radio paging receiver set in the waiting state receives the demodulated signal from the radio section  102 , the decoder  103  checks whether the address of an address signal in the demodulated signal coincides with a self-paging address stored in the ID-ROM  105  (step S 2 ).  
         [0075]    When it is determined that the addresses do not coincide with each other (NO in step S 2 ), the flow returns to the waiting state in step S 1 .  
         [0076]    When it is determined that the addresses coincide with each other (YES in step S 2 ), a driving signal is supplied, through the driver  104 , to any one of the light-emitting diode  110 , the loudspeaker  111 , and the vibrator  112  which is designated to be driven by the notifying means driving switch of the switches  115 , so that the light-emitting diode  110 , the loudspeaker  111 , or vibrator  112  notifies a user of being paged (step S 3 ).  
         [0077]    Thereafter, the decoder  103  checks whether a state of the dot count change switch of the switches  115  which designates whether the number of dots of a display unit is changed in accordance with the number of characters of a message is set to be “changeable dot count” or “fixed dot count”,(step S 4 ).  
         [0078]    When it is determined that the state of the dot count change switch is set to be “fixed dot count” (NO in step S 4 ), the decoder  103  checks whether a paging signal sent from the radio section  102  contains a message (step S 5 ).  
         [0079]    When it is determined that the paging signal contains the message (YES in step S 5 ), the decoder  103  sends a status of “presence of message”, a status of “fixed dot count”, incoming call time and date, and the message itself to the CPU  106  (step S 6 ). When it is determined that the paging signal does not contain a message (NO in step S 5 ), the decoder  103  sends a status of “absence of message” and the incoming call time and date to the CPU  106  (step S 7 ). Note that the decoder  103  has a time calculating function and a calendar calculating function, and incoming call time and date are determined by these functions.  
         [0080]    When it is determined in step S 4  that the state of the dot count change switch is set to be “changeable dot count” (YES in step S 4 ), the decoder  103  checks whether the paging signal sent from the radio section  102  contains amessage (step S 8 ).  
         [0081]    When it is determined that the paging signal does not contain a message (NO in step S 8 ), processing in step S 7  is performed. When it is determined that the paging signal contains a message (YES in step S 8 ), the decoder  103  sends a status of “presence of message”, a status of “changeable dot count”, incoming call time and date, and the message itself to the CPU  106  (step S 9 ).  
         [0082]    When the CPU  106  receives a message and various statuses from the decoder  103 , the CPU  106  stores the message and statuses in a RAM (not shown) arranged in the CPU  106  (step S 10 ).  
         [0083]    Thereafter, the CPU  106  checks whether a status indicating the presence/absence of the message stored in the RAM is set to be “absence of message” (step S 11 ).  
         [0084]    When it is determined that the status is set to be “absence of message” (YES in step S 1 ), the CPU  106  sends the status of “absence of message” and the incoming call time and date to the display driver  107  (step S 12 ).  
         [0085]    The display driver  107  reads, from the character generator  109 , display data “TONE ONLY” corresponding to the status of “absence of message” sent from the CPU  106 , and the waveform of the display data is sent to the liquid crystal display section  108 . A control signal for displaying the incoming call time and date sent from the CPU  106  is added to the liquid crystal display section  108 , and the display contents of the liquid crystal display section  108  are shown in FIG. 20.  
         [0086]    When it is determined that the status is set to be “presence of message” (NO in step S 11 ), the CPU  106  checks whether a status indicating whether the dot count of a unit display component is changeable is set to be “changeable dotcount” (step S 14 ).  
         [0087]    When it is determined that the status is set to be “changeable dot count” (YES in step S 14 ), the CPU  106  calculates the number L of characters of a message stored in the RAM arranged in the CPU  106  (step S 15 ).  
         [0088]    When it is determined the number L of characters of the message satisfies L≦12, the CPU  106  sends, to the display driver  107 , a status designating that the dot count of a unit display component is set to be D 1  (step S 16 ), and the CPU  106  sends the message and incoming call time and date to the display driver  107  (step S 17 ).  
         [0089]    When the display driver  107  receives the status designating that the dot count of a unit display component is set to be D 1 , and then receives a message (e.g., “045-939-2314”), the display driver  107  reads display data corresponding to the message and the dot count D 1  from the character generator  109  and supplies the display waveform of the display data to the liquid crystal display section  108 . In addition, when the display driver  107  receives incoming call time and date, the display driver  107  supplies a control signal for displaying the incoming call time and date to the liquid crystal display section  108 , and the displayed contents of the liquid crystal display section  108  are shown in FIG. 21 (step S 18 ).  
         [0090]    When it is determined in step S 15  that the number L of characters of a message satisfies 13≦L≦27, the CPU  106  sends, to the display driver  107 , a status designating that the dot count of a unit display component is set to be D 2  (step S 19 ), and the CPU  106  sends a message and incoming call time and date to the display driver  107  (step S 20 ). Note that the dot count D 2  is smaller than the dot count D 1 .  
         [0091]    When the display driver  107  receives the status designating that the dot count of a unit display component is set to be D 2 , and then receives a message (e.g., “Mr. Sato called you. Call him”, the display driver  107  reads display data corresponding to the message and the dot count D 2  from the character generator  109  and supplies the display waveform of the display data to the liquid crystal display section  108 . In addition, when the display driver  107  receives incoming call time and date, the display driver  107  supplies a control signal for displaying the incoming call time and date to the liquid crystal display section  108 , and the display contents of the liquid crystal display section  108  are shown in FIG. 22 (step S 21 ).  
         [0092]    When it is determined in step S 15  that the number L of characters of the message satisfies L&gt;28, the CPU  106  sends, to the display driver  107 , a status designating that the dot count of a unit display component is set to be D 3  (step S 22 ), and the CPU  106  checks whether the number L satisfies L≧49 (step S 23 ). Note that the dot count D 3  is smaller than the dot count D 2 .  
         [0093]    When it is determined in step S 23  that the number L satisfies L&lt;49 (NO in step S 23 ), the CPU  106  sends the message and the incoming call time and date to the display driver  107  (step S 24 ).  
         [0094]    When the display driver  107  receives the status designating that the dot count of a unit display component is set to be D 3 , and thereafter receives a message (e.g., “Urgent meeting will be held. Cancel others.”), the display driver  107  reads display data corresponding to the message and the dot count D 3  from the character generator  109  and supplies the display waveform of the display data to the liquid crystal display section  108 . In addition, when the display driver  107  receives incoming call time and date, the display driver  107  supplies a control signal for displaying the incoming call time and date to the liquid crystal display section  108 , and the display contents of the liquid crystal display section  108  are shown in FIG. 23 (step S 25 ).  
         [0095]    When it is determined in step S 23  that the number L of characters of the message satisfies L≧49, the CPU  106  sends the first forty-eight characters of a message (e.g., “Urgent meeting will be held. Cancel others and come back. We informed our client of it.”) stored in the RAM in the CPU  106 , the incoming call time and date, and a next screen message continuation mark display command to the display driver  107  (step S 26 ).  
         [0096]    When the display driver  107  receives the message corresponding to the forty-eight characters, the display driver  107  reads display data corresponding to the message and the dot count D 3  from the character generator  109  and supplies the display waveform of the display data to the liquid crystal display section  108 . In addition, when the display driver  107  receives incoming call time and date and the next screen message continuous mark display command, the display driver  107  supplies, to the liquid crystal display section  108 , a control signal for displaying the incoming call time and date and the next screen message continuous mark display, and the display contents of the liquid crystal display section  108  are shown in FIG. 24A (step S 27 ).  
         [0097]    Thereafter, the CPU  106  checks whether the number of remaining characters of the message is forty-eight or less (step S 28 ).  
         [0098]    When it is determined that the number of remaining characters is not forty-eight or less (NO in step S 28 ), and the next screen display switch included in the switches  115  is operated, the flow returns to processing of step S 26 , and a message corresponding to the forty-eight characters is displayed on the liquid crystal display section  108 .  
         [0099]    When it is determined that the number of remaining characters is forty-eight or less (YES in step S 28 ), and the next screen display switch of the switches  115  is operated, the remaining characters of the message and the incoming call time and date are sent to the display driver  107  (step S 29 ).  
         [0100]    When the display driver  107  receives the remaining characters of the message, the display driver  107  reads display data corresponding to the message and the dot count D 3  from the character generator  109  and supplies the display waveform of the display data to the liquid crystal display section  108 . In addition, when the display driver  107  receives incoming call time and date, the display driver  107  supplies, to the liquid crystal display section  108 , a control signal for displaying the incoming call time and date on the liquid crystal display section  108 , and the display contents of the liquid crystal display section  108  are shown in FIG. 24B (step S 30 ).  
         [0101]    When it is determined in step S 14  that the status indicating whether the dot count of a unit display component is changeable is set to be “fixed dot count”, the CPU  106  sends, to the display driver  107 , the status designating that the dot count of a unit display component is set to be D 2  (step S 34 ). Then, the CPU  106  checks whether the number L of characters of a message stored in the RAM arranged in the CPU  106  satisfies L≧28 (step S 35 ).  
         [0102]    When it is determined that the number L does not satisfy L≧28 (NO in step S 35 ), the CPU  106  sends the message and the incoming call time and date to the display driver  107  (step S 36 ).  
         [0103]    When the display driver  107  receives a message (e.g., “Please call our office.”, the display driver  107  reads display data corresponding to the message and the dot count D 2  from the RAM, supplies the display waveform of the display data to the liquid crystal display section  108 , and supplies, to the liquid crystal display section  108 , a control signal for displaying the incoming call time and date, and the display contents of the liquid crystal display section  108  are shown in FIG. 25 (step S 37 ).  
         [0104]    When it is determined that the number L satisfies L≧28 (YES in step S 35 ), the CPU  106  sends a message corresponding to the first twenty-seven characters of the message (e.g., “Please call soon Mr. Suzuki, 03-1234-5678.”) stored in the RAM arranged in the CPU  106 , incoming call time and date, and a next screen message continuous mark display command to the display driver  107  (step S 38 ).  
         [0105]    When the display driver  107  receives the message corresponding to the first twenty-seven characters, the display driver  107  reads display data corresponding to the message and the dot count D 2  from the character generator  109  and supplies the display waveform of the display data to the liquid crystal display section  108 . In addition, when the display driver  107  receives the incoming call time and date and the next screen message continuous mark display command, the display driver  107  supplies, to the liquid crystal display section  108 , a control signal for displaying the incoming call time and date and the next screen message continuous mark, and the display contents of the liquid crystal display section  108  are shown in FIG. 26A.  
         [0106]    Thereafter, the CPU  106  checks whether the number of remaining characters of the message is twenty-seven or less (step S 40 ).  
         [0107]    When it is determined that the number of remaining characters of the message is not twenty-seven or less (NO in step  40 ), and the next screen display switch of the switches  115  is operated, the flow returns to the processing in step S 38 , and a message corresponding to the next twenty-seven characters is displayed on the liquid crystal display section  108 .  
         [0108]    When it is determined that the number of remaining characters of the message is twenty-seven or less (YES in step S 40 ), and the next screen switch is operated, the CPU  106  sends the remaining characters of the message and the incoming call time and date to the display driver  107  (step S 41 ).  
         [0109]    When the display driver  107  receives a message, the display driver  107  reads display data corresponding to the message and the dot count D 2  from the character generator  109  and supplies the display waveform of the display data to the liquid crystal display section  108 . In addition, when the display driver  107  receives the incoming call time and date, the display driver  107  supplies a control signal for displaying the incoming call time and date to the liquid crystal display section  108 , and the display contents of the liquid crystal display section  108  are shown in FIG. 26B (step S 42 ).  
         [0110]    Upon completion of display of messages (processing in steps S 18 , S 21 , S 25 , S 30 , S 37 , and S 42  is completed), the CPU  106  performs key-scanning of the display erasing switch of the switches  115  and timer calculation. When the CPU  106  detects depression of the display erasing switch (YES in step S 31 ), or when the CPU  106  detects that the timer (about 20 seconds in general) is turned off, erasure of the message is designated to the display driver  107 . Thereafter, the flow returns to step S 1 .  
         [0111]    It should be understood that the foregoing relates to only preferred embodiments of the present invention, and the present invention is not limited to these embodiments. It will be obvious to those skilled in the art that various modifications and changes can be made without departing from the spirit and scope of the invention.