Abstract:
A dialing method for a telephone system begins by receiving a caller indentification (i.e., telephone number) of a party calling the telephone system. The received caller identification is then stored in a control buffer of the telephone system. A control unit of the telephone system determines whether the caller identification stored in the control buffer is identical to one of a plurality of existing caller identifications stored in a memory of the telephone system. When the caller identification stored in the control buffer is identical to one of the existing caller identifications stored in the memory, the existing caller identification that is identical to the caller identification is deleted from the memory. The caller identification is then transferred from the control buffer to the memory, and stored in the memory according to a last in first out rule. The caller identification is displayed on a display unit of the telephone system in response to a first input of a search key. Then, the telephone number corresponding to the caller identification is automatically dialed in response to input of a start key.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application makes reference to, incorporates the same herein, and claims all benefits accruing under 35 U.S.C. §119 arising from an application for Automatic Dialing Method Using Caller Identification earlier filed in the Korean Industrial Property Office on Dec. 20, 1995 and there duly assigned Serial No. 52606/1995. 
     BACKGROUND OF THE INVENTION 
     The present invention relates to an automatic dialing method for a telephone system using a caller identification (ID), and more particularly, to a method of automatically registering a detected caller identification (ID) in a memory of a telephone system to optimally enable dialing of a telephone number corresponding to the detected caller identification (ID). 
     Caller identification (ID) is a feature provided by many conventional telephone systems. According to this feature, a caller&#39;s telephone number is sent together with a ring signal during an incoming call. The caller&#39;s telephone number is then displayed for a user, so that the user can know who is calling before deciding to answer the call. As a result, the user can be prevented from wasting time or labour due to an unwanted telephone call. 
     Several prior art references discuss the concept of caller identification (ID) in a telephone system. U.S. Pat. No. 5,452,346 entitled Telephone Apparatus With Caller Identification issued to Miyamoto, for example, discloses a specific design for a telephone system employing caller identification (ID). In Miyamoto &#39;346, a decoder detects and decodes telephone number information of a calling side that is transmitted through a telephone line. A memory stores telephone number data of calling sides in correspondence with operation keys. When a call is received, a comparison circuit compares output data from the decoder with the telephone number data stored in memory. If a coincidence is detected between the output data of the decoder and the telephone number data in the memory, an output device notifies a user that the call corresponds to one of the telephone numbers stored in memory. While conventional art, such as Miyamoto &#39;346, provides a telephone system user with certain benefits, I note that it fails to automatically register caller identifications (IDs) in a manner so as to optimally facilitate an automatic dialing operation. 
     SUMMARY OF THE INVENTION 
     Accordingly, it is an object of the present invention to provide an improved method for detecting a caller identification (ID) provided with a ring signal, and automatically registering the caller identification (ID) in a memory of a telephone system. 
     It is another object to provide a method for automatically registering a detected caller identification (ID) in a memory of a telephone system according to a last in first out rule. 
     It is still another object to provide a method for automatically registering a detected caller identification (ID) in a memory of a telephone system to optimally enable dialing of a telephone number corresponding to the detected caller identification (ID). 
     To achieve these and other objects, the present invention provides a dialing method for a telephone system that begins by receiving a caller indentification (i.e., telephone number) of a party calling the telephone system. The received caller identification is then stored in a control buffer of the telephone system. A control unit of the telephone system determines whether the caller identification stored in the control buffer is identical to one of a plurality of existing caller identifications stored in a memory of the telephone system. When the caller identification stored in the control buffer is identical to one of the existing caller identifications stored in the memory, the existing caller identification that is identical to the caller identification is deleted from the memory. The caller identification is then transferred from the control buffer to the memory, and stored in the memory according to a last in first out rule. The caller identification is displayed on a display unit of the telephone system in response to a first input of a search key. Then, the telephone number corresponding to the caller identification is automatically dialed in response to input of a start key. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     A more complete appreciation of the invention, and many of the attendant advantages thereof, will be readily apparent as the same becomes better understood by reference to the following detailed description when considered in conjunction with the accompanying drawings in which like reference symbols indicate the same or similar components, wherein: 
     FIG. 1 is a block diagram of a telephone system constructed according to the principles of the present invention. 
     FIG. 2 is a waveform diagram of a ring signal containing a caller identification (ID) received from an office exchange. 
     FIG. 3 is a memory map in which the caller identification (ID) is registered according to the principles of the present invention. 
     FIG. 4 is a flow chart of steps for registering a received caller identification (ID) according to the principles of the present invention. 
     FIG. 5 is a flow chart of steps for searching for a registered caller identification (ID) according to the principles of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Turning now to the drawings and referring to FIG. 1, a telephone system constructed according to the principles of the present invention is shown. In FIG. 1, a control unit  110  controls the overall operation of the telephone system, and includes an interior buffer for temporarily registering a caller identification (ID) (i.e., a caller&#39;s telephone number) received through a public switched telephone network (PSTN). Control unit  110  also enables the temporarily registered caller identification (ID) to be transferred and registered in a memory  118 , and controls an operation of searching for a registered caller identification (ID). A ring detecting unit  112  is connected to the public switched telephone network (PSTN). The ring detecting unit  112  detects a ring signal received through the public switched telephone network (PSTN), and transmits the ring signal to control unit  110 . A line signal detecting unit  114  detects the caller identification (ID) (i.e., a caller&#39;s telephone number) received through the public switched telephone network (PSTN), and provides the caller identification (ID) to control unit  110 . A talking circuit unit  116  is connected to the public switched telephone network (PSTN) through a hook switch (H/S), and interfaces various tone signals and vocal signals between a telephone speech network and the public switched telephone network (PSTN). Memory  118  is used to register the caller identifications (IDs) according to a reception sequence after they are detected by line signal detecting unit  114 . Memory  118  also reads selected caller identifications (IDs), and provides the selected caller identifications (IDs) to control unit  110 . A transceiver  120  includes a transmitter which converts a user&#39;s vocal signal into an electrical signal for output to talking circuit unit  116 , and a receiver which converts an electrical signal received from talking circuit unit  116  into an audible sound (i.e., voice). A display unit  132  displays the present operating state of the telephone system, and displays the caller identification (ID) selected during the searching of the caller identifications (IDs) registered in memory  118  under the control of control unit  110 . A key input unit  124  includes: a search key for searching for caller identifications (IDs) registered in memory  118 , a start key for automatically dialing the telephone number corresponding to the selected caller identification (ID), and a stop key for terminating the search of caller identifications (IDs). Key input unit  124  also generates key instructions and data according to a key input, and provides them to control unit  110 . Hook switch (H/S) having a hook relay connects the public switched telephone network (PSTN) to talking circuit unit  116  under the control of control unit  110 . 
     FIG. 2 is a waveform diagram of a ring signal containing a caller identification (ID) received from an office exchange, and FIG. 3 is a memory map in which the caller identification (ID) is registered according to the principles of the present invention. 
     Reference character  3   a  of FIG. 3 shows the structure of memory  118  shown in FIG.  1 . Memory  118  includes ten data buffers (Call_Bank) in which the detected caller identification (ID) is automatically registered. Each data buffer provides twenty (20) bytes of data storage capacity. The ten data buffers are operated according to a “last in first out” (LIFO) rule. Reference characters  3   b - 1  and  3   b - 2  of FIG. 3 show a preferred embodiment for registering a detected caller identification (ID) when the detected caller identification (ID) has not previously been registered in the data buffers (Call_Bank). Alternatively, reference characters  3   c - 1  and  3   c - 2  of FIG. 3 show a preferred embodiment for registering a detected caller identification (ID) when the detected caller identification (ID) has previously been registered in the data buffers (Call_Bank). 
     FIG. 4 is a flow chart of steps for registering a received caller identification (ID) according to the principles of the present invention. Briefly, the flow chart of FIG. 4 includes the steps of: detecting a caller identification (ID) received during an incoming call, temporarily storing the detected caller identification (ID) in an inner buffer of control unit  110 , determining whether the detected caller identification (ID) has previously been registered in memory  118 , registering the detected caller identification (ID) in memory  118  after eliminating identical caller identification (ID) from memory  118  when the detected caller identification (ID) has previously been registered in memory  118 , and registering the detected caller identification (ID) as new caller identification (ID) when the detected caller identification (ID) has not previously been registered in memory  118 . 
     FIG. 5 is a flow chart of steps for searching for a registered caller identification (ID) according to the principles of the present invention. Briefly, the flow chart of FIG. 5 includes the steps of: sequentially displaying caller identifications (IDs) in response to successive inputs of the search key, connecting a call by automatically dialing a telephone number corresponding to the displayed caller identification (ID) when the start key is input, and finishing the search for caller identification (ID) when the stop key is input. 
     With reference to the appended drawings, the preferred embodiments of the present invention will now be described in detail. 
     As shown in FIG. 4, control unit  110  first determines whether a caller identification (ID) is detected by line signal detecting unit  114 , in step  410 . When a caller identification (ID) is detected by line signal detecting unit  114 , control unit  110  temporarily stores the detected caller identification (ID) in the inner buffer, in step  412 . Control unit  110  then sets a count variable n to a value of 9, in step  414 . The count variable n is used for checking the caller identifications (IDs) registered in the ten buffers (Call_Bank[ 0 ]-Call_Bank[ 9 ]) of memory  118 . Next, control unit  110  determines whether the count variable n is greater than or equal to 0, in step  416 . When the count variable n is greater than or equal to 0, the caller identification (ID) temporarily stored in the inner buffer of control unit  110  is compared with the caller identification (ID) registered in the nth buffer (Call_Bank[n]) of memory  118  (see  3   a  of FIG. 3) to determine whether they are identical, in step  418 . When the caller identifications (IDs) are different, the count variable n is decremented by one in step  420 , and step  416  is again performed. 
     When the detected caller identification (ID) has not previously been registered in memory  118 , steps  416  to  420  are repeated until the count variable n is less than 0. When this condition is detected in step  416 , control unit  110  sets the count variable n to a value of 8, in step  424 . The count variable n is set to 8 in order to transfer each caller identification (ID) registered in memory  118  from a present buffer (Call_Bank[n]) to a next buffer (Call_Bank[n−1]). Control unit  110  then determines whether the count variable n is greater than or equal to 0, in step  426 . When the count variable n is greater than or equal to 0 in step  426 , the caller identification (ID) registered in the nth buffer of memory  118  (Call_Bank[n]) is transferred to the next buffer (Call_Bank[n+1]), in step  428 . Then, the count variable n is decremented by one in step  430 , and step  426  is again performed. 
     After all of the caller identifications (IDs) registered in memory  118  have been transferred to the next buffer (Call_Bank[n+1]) through the repetition of steps  428  to  430 , the count variable n will exhibit a value that is less than 0. When this condition is detected in step  426 , control unit  110  stores the caller identification (ID) temporarily stored in its inner buffer in the buffer  0  (Call_Bank[ 0 ]) in step  432 , and the procedure ends. 
     Referring back to FIG. 3, the technique for registering detected caller identification (ID) when the detected caller identification (ID) has not previously been registered in memory  118  will now be described using reference characters  3   b - 1  and  3   b - 2 . 
     When a caller identification (ID) “A” is detected under the condition that caller identifications (IDs) are registered in memory  118  according to the format shown by reference character  3   b - 1  of FIG. 3, control unit  110  temporarily stores caller identification (ID) “A” in its inner buffer having 20 bytes of data storage capacity. Control unit  110  then compares caller identification (ID) “A” with each of the caller identifications (IDs) registered in buffers (Call_Bank[ 0 ]-Call_Bank[ 9 ]) of the memory  118 . Since caller identification (ID) “A” has not previously been registered in the buffers (Call_Bank[ 0 ]-Call_Bank[ 9 ]) of memory  118 , caller identification (ID) “B” to caller identification (ID) “E”, which are registered in the buffers (Call_Bank[ 0 ]-Call_Bank[ 8 ]), are transferred and registered as indicated by reference character  3   b - 2  of FIG.  3 . The caller identification (ID) “F” registered in buffer  9  (Call_Bank[ 9 ]) of  3   b - 1  is eliminated, and the newly detected caller identification (ID) “A” is registered in buffer  0  (Call_Bank[ 0 ]). Reference character  3   b - 2  of FIG. 3 represents a map of the buffers (Call_Bank[ 0 ]-Call_Bank[ 9 ]) of memory  118  after the registering steps are completed. 
     Alternatively, when a detected caller identification (ID) has previously been registered in memory  118 , this condition is recognized in step  418  of FIG. 4, and the steps for re-registering the detected caller identification (ID) in memory  118  will be as follows. 
     Control unit  110  decrements the count variable n by one in step  422 . This is performed to eliminate the identical caller identification (ID) which has already been registered in the nth buffer (Call_Bank[n]), and transfer the registered caller identification (ID) to a preceding buffer (Call_Bank[n−1]). After control unit  110  has transferred all of the caller identifications (IDs) from the buffers n−1 (Call_Bank[n−1]) to  0  (Call_Bank[ 0 ]) through steps  426  to  430 , the count variable n becomes less than 0, and control unit  110  stores the caller identification (ID) temporarily stored in its inner buffer in the buffer  0  (Call_Bank[ 0 ]), in step  432 . 
     The technique for registering detected caller identification (ID) when the detected caller identification (ID) has previously been registered in memory  118  will now be described using reference characters  3   c - 1  and  3   c - 2  of FIG.  3 . 
     When a caller identification (ID) “A” is detected under the condition that caller identifications (IDs) are registered in memory  118  according to the format shown by reference character  3   c - 1  of FIG. 3, control unit  110  temporarily stores caller identification (ID) “A” in its inner buffer having 20 bytes of data storage capacity. Control unit  110  then compares caller identification (ID) “A” with each of the caller identifications (IDs) registered in buffers (Call_Bank[ 0 ]-Call_Bank[ 9 ]) of the memory  118 . Since the caller identification (ID) “A” has already been registered in buffer  2  (Call_Bank[ 2 ]) of memory  118 , as indicated by reference character  3   c - 1  of FIG. 3, it is eliminated from buffer  2  (Call_Bank[ 2 ]). The caller identification (ID) “C” registered in buffer  1  (Call_Bank[ 1 ]) is then transferred to buffer  2  (Call_Bank[ 2 ]), as indicated by reference character  3   c - 2  of FIG.  3 . Moreover, caller identification (ID) “B” is transferred from buffer  0  (Call_Bank[ 0 ]) to buffer  1  (Call_Bank[ 1 ]). The new caller identification (ID) “A” temporarily stored in the inner buffer of control unit  110  is registered in buffer  0  (Call_Bank[ 0 ]). Consequently, reference character  3   b - 2  of FIG. 3 represents a map of the buffers (Call_Bank[ 0 ]-Call_Bank[ 9 ]) of memory  118  after the registering steps are completed. 
     Referring now to FIG. 5, a flow chart of steps for searching for a registered caller identification (ID) according to the principles of the present invention will be described in detail. 
     In step  510 , control unit  110  determines whether any key is input from the key input unit  124 . When any key input from key input unit  124  is detected in step  510 , control unit  110  determines whether the key is the search key, in step  512 . When the key is the search key, the count variable n is set to 0, in step  514 . The count variable n is set to 0 so that the caller identification (ID) registered in buffer  0  is output prior to any other caller identifications (IDs). That is, the count variable n is set to 0 to enable execution of the “last in first out” (LIFO) rule. Next, in step  516 , control unit  110  determines whether the count variable n is greater than nine, which represents the last buffer (Call_Bank[ 9 ]). When the count variable n is greater than 9, the count variable n is reset in step  514 . Alternatively, when the count variable n is not greater than 9, control unit  110  enables the caller identification (ID) registered in buffer n (Call_Bank[n]) to be displayed through the display unit  122 . Since the count variable n was set to 0 in step  514 , the caller identification (ID) registered in buffer  0  (Call_Bank[ 0 ]) is displayed first. 
     While the caller identification (ID) registered in buffer n (Call_Bank[n]) is displayed, control unit  110  determines whether any key is input from the key input unit  124 , in step  520 . When a key input from the key input unit  124  is not provided within a predetermined time, this condition is detected in step  532 , and the process ends. Alternatively, when a key input from key input unit  124  is provided within the predetermined time, control unit  110  determines whether the key is the search key, in step  522 . When the key is the search key, control unit  110  increments the count variable n by one, in step  524 , and enables display of the caller identification (ID) registered in the next buffer (Call_Bank[n]) on the display unit  122  through steps  516  to  518 . On the other hand, when the key is not the search key, but the start key, this condition is detected in step  526 . Control unit  110  responds to input of the start key by automatically dialing the telephone number corresponding to the caller identification (ID) displayed on display unit  122 , in step  528 . Alternatively, when the key is the stop key, this condition is detected in step  530 . Control unit  110  responds to input of the stop key by ending the process. 
     As described above, the present invention automatically registers a caller identification (ID) (i.e., a caller&#39;s telephone number) after detecting it from an incoming ring signal. Accordingly, it is possible to reduce the annoyance caused by an obscene or threatening call, and a user can know a telephone number received in his absence. Moreover, the user can advantageously dial a caller&#39;s telephone number through a simplified process. 
     While there have been illustrated and described what are considered to be preferred embodiments of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made, and equivalents may be substituted for elements thereof without departing from the true scope of the present invention. In addition, many modifications may be made to adapt a particular situation to the teaching of the present invention without departing from the central scope thereof. Therefore, it is intended that the present invention not be limited to the particular embodiments disclosed as the best mode contemplated for carrying out the present invention, but that the present invention includes all embodiments falling within the scope of the appended claims.