Abstract:
Methods performed by handsets such as cell phones of receiving a notification of a remotely stored message, the notification including message parameters related to the message, monitoring those parameters for a parameter selected via a user interface of the handset and requesting an action be performed on the message when the parameter matches the selected parameter, such as forwarding all messages of a given type to another destination.

Description:
This application is a continuation of U.S. patent application Ser. No. 14/225,727, filed Mar. 26, 2014 (pending), which is a division of U.S. patent application Ser. No. 13/895,226, filed May 15, 2013 (pending), which is a division of U.S. patent application Ser. No. 12/973,722, filed Dec. 20, 2010 (pending), which is a division of U.S. application Ser. No. 11/598,202, filed Nov. 13, 2006 (now U.S. Pat. No. 8,107,601), which is a continuation of U.S. application Ser. No. 10/445,257, filed May 27, 2003 (status: Abandoned), which is a continuation of U.S. application Ser. No. 09/540,490, filed Mar. 31, 2000 (now U.S. Pat. No. 6,636,733), and which is a continuation-in-part of U.S. application Ser. No. 09/408,841, filed Sep. 30, 1999 (now U.S. Pat. No. 6,826,407), which claims the benefit of U.S. Provisional Application No. 60/155,055, filed Sep. 21, 1999 and U.S. Provisional Application No. 60/126,939, filed Mar. 29, 1999; U.S. patent application Ser. No. 09/540,490 is also a continuation-in-part of U.S. application Ser. No. 08/934,143, filed Sep. 19, 1997 (now U.S. Pat. No. 6,233,430), U.S. application Ser. No. 08/933,344, filed Sep. 19, 1997 (now U.S. Pat. No. 6,253,061), U.S. application Ser. No. 08/934,132, filed Sep. 19, 1997 (now U.S. Pat. No. 6,087,956), U.S. application Ser. No. 08/934,337, filed Sep. 19, 1997 (now U.S. Pat. No. 6,259,892), and U.S. application Ser. No. 08/989,874, filed Dec. 12, 1997 (now U.S. Pat. No. 6,097,941). All of the above mentioned applications (provisional and non-provisional) are incorporated in their entirety herein by this reference. 
    
    
     Reference is made to the following co-pending and patented patent applications: (1) Ser. No. 13/763,970 (now U.S. Pat. No. 8,560,006); (2) Ser. No. 13/210,223 (now U.S. Pat. No. 8,498,387); (3) Ser. No. 09/513,998 (now U.S. Pat. No. 6,983,138); (4) Ser. No. 09/688,282 (now U.S. Pat. No. 7,039,428); (5) Ser. No. 09/860,954 (now U.S. Pat. No. 6,462,646); (6) Ser. No. 10/236,932 (now U.S. Pat. No. 6,696,921); (7) Ser. No. 09/688,321 (now U.S. Pat. No. 7,003,304); (8) Ser. No. 09/613,345 (now U.S. Pat. No. 6,459,360); (9) Ser. No. 11/049,869 (now U.S. Pat. No. 7,277,716); (10) Ser. No. 11/050,775 (now U.S. Pat. No. 7,155,241); (11) Ser. No. 11/082,913 (now U.S. Pat. No. 7,280,838); (12) Ser. No. 11/081,611 (now U.S. Pat. No. 7,376,432); (13) Ser. No. 11/082,872 (now U.S. Pat. No. 7,242,951); (14) Ser. No. 11/083,897 (now U.S. Pat. No. 7,403,787); (15) Ser. No. 11/635,781 (now U.S. Pat. No. 7,843,314); (16) Ser. No. 12/367,358 (now U.S. Pat. No. 8,134,450); (17) Ser. No. 12/580,189 (now U.S. Pat. No. 8,224,294); (18) Ser. No. 12/764,025 (now U.S. Pat. No. 7,835,757); (19) Ser. No. 13/109,389 (now U.S. Pat. No. 8,355,702); (20) Ser. No. 11/108,759 (now U.S. Pat. No. 7,146,157); (21) Ser. No. 11/399,513 (now U.S. Pat. No. 7,499,716); (22) Ser. No. 11/105,441 (now U.S. Pat. No. 7,627,305); (23) Ser. No. 12/625,357 (now U.S. Pat. No. 7,957,695); (24) Ser. No. 10/958,731 (now U.S. Pat. No. 8,099,046); (25) Ser. No. 12/167,971 (now U.S. Pat. No. 8,116,741); (26) Ser. No. 11/598,832 (now U.S. Pat. No. 8,116,743); (27) Ser. No. 12/267,436 (now U.S. Pat. No. 8,295,450); and (28) Ser. No. 13/109,437 (now U.S. Pat. No. 8,374,585). 
     FIELD OF THE INVENTION 
     The present invention relates generally to paging transceivers, systems and methods for selectively acting on messages, paging and, more particularly, to paging systems and transceivers and methods for selectively paging in response to or retrieving messages received, erasing information stored at a plurality of sources including the paging transceivers or at remote locations. The present invention also relates generally to the field of communication systems, and more particularly to systems for allowing users to access and manage voice and other messages. The present invention also relates to wireless messaging devices such as two-way pagers, wireless telephones and personal digital assistants (PDA&#39;s) and, electronic media systems such as, electronic mail systems, electronic commerce systems and storage and retrieval systems. More specifically, the present invention relates to two-way wireless email devices and associated systems. 
     BACKGROUND OF THE INVENTION 
     In general, a paging receiver can be classified into one of four categories: an alert or tone only paging receiver, a numeric paging receiver, an alphanumeric paging receiver, or a voice paging receiver. One common characteristic of all of these paging receivers is that they monitor the air waves and notify the user when their particular address has been detected. For the alert or tone only paging receiver, the paging receiver would generate a tone or beep when its address is detected. The other paging receivers, upon detecting their address, would additionally store a message associated with the address signal and display or play it to the user. The message for a numeric paging receiver would be a set of numbers, typically the calling person&#39;s telephone number, and the message for an alphanumeric paging receiver would be a set of numbers and/or letters. The user of an alphanumeric paging receiver could therefore receive a message in the form of a telephone number with some descriptive text. For the voice paging receiver, the message that is stored is a voice message that the user can later play to hear the message. 
     A paging receiver is typically a rather small electronic device and, accordingly, has a limited amount of memory for storing messages that have been received from a base station in a paging system. Because of the relatively small size of the memory, the paging receiver can store only a limited number of messages. A user can delete messages from memory but will oftentimes desire to save a message, such as temporarily until the user makes a note of the message or until he or she is able to respond to the page. The messages that are saved in memory, however, reduce the space in memory that is available to receive new messages. This demand on space in memory is increasing as the size of the messages continue to grow and as users receive a greater number of messages. Although more memory can be added to accommodate more messages, the added cost and space needed for extra memory runs counter to the desires to keep the paging receiver small and inexpensive. A need therefore exists for a paging receiver which can display and/or play messages while efficiently using memory. 
     In addition to the demand on paging receiver memory, paging systems will be challenged as greater numbers of pages are being transmitted and as the size of the transmitted messages increases. Initially, when paging systems were only concerned with transmitting address signals of the paging receivers, the size of each transmission by the paging systems was relatively small. Paging receivers and paging systems, however, have undergone tremendous advances with paging systems now transmitting messages which can be hundreds of kilobytes or greater in size in addition to the address signals. Additionally, many paging receivers are actually paging transceivers which transmit acknowledgment signals back through the paging system. The capacity of the paging systems are therefore being challenged not only by messages of increasing sizes but also by reply signals transmitted from the paging transceivers to the paging system. The future of paging systems is therefore tied to the ability of the paging systems to control the number and size of the data transmissions and to provide additional features without sacrificing the quality of service to the user. 
     As discussed above, many paging transceivers are able to issue a reply or acknowledgment back to the base station in response to a received message. If the base station does not receive this reply or acknowledgment, then the base station assumes that the message has not been received and will repeatedly transmit the message until the reply or acknowledgment is received. Due to the high power levels at which the base station transmits its paging signals, the signals are usually easily received by all paging transceivers located within the coverage area of the base station antenna. The paging transceivers, on the other hand, must operate at lower power levels and often cannot transmit signals at sufficiently high levels to reach the base station. For example, when a paging transceiver is located in a basement of a building, in a subway, or in an airplane, the paging transceiver may be unable to issue a reply that can reach the base station. As a result, the base station may continue to transmit a page to a paging transceiver and the paging transceiver will continue to receive the message but the base station cannot detect the reply being issued by the paging transceiver. This unnecessary transmission of duplicate messages and the ineffectual reply signals transmitted by the paging transceivers consume valuable resources of the paging system and of the paging transceiver. 
     For safety reasons, a user may at times have to turn off his or her paging transceiver. For instance, when the user is on an airplane, the transmissions from the paging transceiver can interfere with the instrumentation or communication within the cockpit of the plane. The paging transceiver therefore should not be operating within the plane or around other electronic equipment that are sensitive to interference from the signals transmitted by the paging transceiver. As another example, if the user is in an environment that contains electronic detonators for explosive materials, the signals transmitted by the paging transceiver could possibly trigger an explosion. The user therefore must turn his or her paging transceiver off to ensure that it does not transmit any reply or acknowledgment signals in response to a received page. Although it may be dangerous for the pager transceivers to issue a reply signal in these situations, the signals transmitted by the base station may at times be safely received by the paging transceiver. Since the paging transceiver automatically issues a reply in response to a received message, the paging transceiver must nonetheless be turned off so as to not pose a risk to the user. During these times that the paging transceiver must be turned off, the user unfortunately is unable to receive any page or message. A need therefore exists for a paging transceiver that can notify a user of a message without automatically generating a reply message or acknowledgment to the base station. 
     Recent ubiquity of mobile communications systems and devices increases demand for remote access to and ability to manage voice messages and similar messages, records or files. Conventional remote voice message access generally occurs through mobile telephony devices or through pagers. Such conventional approaches typically require users to master a sophisticated list of commands, rules, procedures and protocols in order to access and manage voice mail even on one platform. For instance, simply to forward a message may require the user to know that the forward command is “73,” which should not be confused with the reply all command “74.” This command then presents the user with a voice menu which requires time to hear and requires multiple additional keystrokes and commands in order to forward the message. Issues become more tedious and acute in mobile telephony, where users on cell phones who may be driving or in cramped quarters find themselves simply unable to refer to a list of voice mail menu options, and may not have the time required to work through the menu in order to forward the message. Where users maintain an account or mail box on more than one system or provider, they must master multiple sets of such commands, rules, procedures and protocols and the inconvenience and problems intensify. Pagers often do not impose the same level of interface complexity, but for that very reason they typically fail to provide the user an acceptable range of options for accessing and managing voice messages. 
     Conventional mobile approaches to voice mail access and management present other issues. In conventional mobile telephony systems, users may communicate via analog (for example, cellular) or digital (for example, PCS) link with the platform on which voice messages are stored in order to access messages. Such users typically employ standard dual tone multi frequency (DTMF) key interfaces for communicating with, controlling and managing messages on the voice messaging platforms. Such voice mail access and management sessions require excessive bandwidth, however, because the user must be “on line” (in communication via radio link, or otherwise connected or coupled) with the platform and thus occupying radio spectrum. Such sessions can create additional expense to the user and impose extra load upon the telecommunications infrastructure. Such sessions also impose unnecessary demands on the user unit&#39;s power system, upon which radio transmission activities impose a considerable load. 
     U.S. Reissue Pat. No. 34,976 and its antecedent U.S. Pat. No. 5,003,576 to Helferich et al. (Reissued Jun. 20, 1995 and originally issued Mar. 26, 1991) (which disclosures are incorporated herein by this reference) disclose systems in which voice messages and other messages typically created in analog form may be downloaded to cellular telephones and/or other user units for access and management at least partially to address some of these issues. Although such systems disclosed in those documents contemplate transmission of an analog signal, it would also be desirable to download messages via digital radio link such as those conventionally employed in PCS. 
     Another paradigm for considering optimal access and management of voice messages is in the context of paging systems. Paging receivers are typically more efficient than cellular or PCS devices in energy consumption and use of spectrum among other reasons because they are in an active mode or transmit mode for shorter periods of time. User available information, however, is limited to vibration, tone, tone and voice or data messages. Conventional paging systems which include voice retrieval typically use analog voice channels for transmission and reception of voice messages. Accordingly, voice paging systems have been proposed which include user devices that can, via radio link, download, digitize and store voice messages for access and management in the user unit. In this regard, see U.S. Pat. No. 5,455,579 to Bennett, et al. issued Oct. 3, 1995 (which disclosure is incorporated herein by this reference). Such systems allow users to access and download voice messages to pagers or pager like devices in batch mode, but do not allow the user to access and manage the voice messages on the platform where they are initially stored (or other remote platforms) in the event that the user wishes to do so. 
     SUMMARY OF THE INVENTION 
     The present invention solves the problems described above with methods and systems for selective paging. A paging system notifies a paging transceiver that a message has been received but does not initially transmit the associated message. The user, upon being notified of the message, can then download the entire message at a time convenient to the user, which allows the user to download messages at less-expensive off-peak hours and allows the user to place the paging transceiver at a location where it can easily receive the message and reply to the message. Since the messages are not initially transmitted to the paging transceiver, the paging transceiver can receive and store a greater number of pages with minimal increase in the size of memory. Further, because entire messages are not automatically transmitted and since the user can position the paging transceiver to issue a sufficiently strong reply, traffic in the paging system can be controlled and actually reduced. 
     The system may transmit some identifying information about the page to the user without sending the entire message. For instance, the base station may identify the type of message, such as email, voice, or text, and also indicate the caller or other descriptive material about the message. The user can then determine the priority of the message and whether he or she wants to retrieve the message, play the message, erase the message, store the message, forward, reply, or otherwise act on the message. The user is also given control over the messages stored remotely from the paging transceiver and can erase or store these messages from the paging transceiver. The paging transceiver may have a timer for allowing the user to program the paging transceiver to perform a desired function on a message at a particular time. 
     The information initially sent to the user may also indicate the location of the stored message. For instance, the system paging a particular paging transceiver to notify it that a page has been received need not be the system actually storing the content of the message. Instead, a plurality of systems may store the contents of messages with one or more of the systems paging the paging transceiver. The paging transceiver would be provided sufficient information on the system storing the message so that it can communicate with this system. The system paging the paging transceiver can therefore act as a clearinghouse for other messaging systems by notifying a user of all messages received regardless of their source or type. 
     The paging transceivers according to the invention may erase information stored in memory at the paging transceivers or at a remote system. The paging transceiver preferably queries the users as to whether the information should be erased at the paging transceiver or both at the paging transceiver and at the system. If the information is erased only at the paging transceiver, the identifier for the information stored in the memory is not erased. As a result, if the user subsequently desires to retrieve an erased message, the paging transceiver is still able to send the identifier information to the system in order to retrieve the message from the system. Preferably, the paging transceiver does not write over the message in memory whereby if a user subsequently desires the message the message may be recovered without requiring a call to the system. By erasing the information at the system, the user is able to conserve memory space at the system. The paging transceiver therefore provides a user with remote control over remotely stored information. 
     According to the present invention, user devices include an interface which allows the user to access and manage voice messages and other information which is stored on the devices as well as on remote devices to which the user devices may be coupled via radio frequency link. Processes according to the present invention employ user input to such interfaces for access and management of messages stored on the user devices and, when such a device is on line with a remote platform at which the user&#39;s messages are stored, to provide automatic access and management to messages stored there as well. In the event that the user device is not in communication with the remote platform, processes according to the present invention automatically establish a communications session in order to provide such automatic access and message management. 
     Accordingly, it is an object of the present invention to provide systems and methods for paging that conserve memory in paging transceivers. 
     It is another object of the present invention to provide systems and methods for paging that conserve valuable air time. 
     It is a further object of the present invention to provide systems and methods for paging that provide users with remote control over their messages. 
     It is yet another object of the present invention to provide systems and methods for paging that allow users to select when and how action should be taken on their messages. 
     It is yet a further object of the present invention to provide messaging systems and methods for notifying users of received messages. 
     It is also an object of the present invention to provide messaging systems and methods for providing control to users over message stored at remote locations. 
     It is still another object of the present invention to provide messaging systems and methods that notify users of messages received from multiple sources. 
     It is an additional object of the present invention to provide a single user interface which allows a user to access and manage voice messages and other information stored in the user&#39;s device as well as at, in or on remote devices, platforms or locations. 
     It is an additional object of the present invention to allow a user to access and manage messages stored on his or her own user device as well as on remote devices using a single interface and an analog or digital radio frequency link. 
     It is an additional object of the present invention to conserve radio spectrum by enabling efficient access and management of voice messages and other information in a number of locations, on a number of platforms, using a single interface. 
     It is an additional object of the present invention to allow users to access and manage voice messages and other information from any number of other sources stored in any number of locations without requiring the users to be conversant in different access and management interfaces, procedures, rules and protocols for each platform on which messages or information happen to be stored. 
     It is an additional object of the present invention to provide user devices which access and manage voice messages in their own memory capacity, but which also access and manage messages at remote sites via radio frequency link with power efficiencies and with spectrum efficiencies more akin to paging networks than the less efficient (from a power point of view and currently from a spectrum point of view) cellular and PCS voice message systems. 
     It is an additional object of the present invention to provide voice messaging interfaces which feature intuitive and direct commands, such as pushing a designated “forward” button in order to forward a message, and which thus eliminate the need for users to memorize or refer to a list of commands in order to access and manage voice messages. 
     Another object of the invention is to provide a messaging system for selectively performing an action on information, for remote retrieval of messages, for performing action on information at different times, for selective paging, for providing a user interface for message access and having integrated audio visual messaging. Another object of the invention is to provide a method and system for wireless retrieval of an email attachment such as an audio or video file. 
     Another object of the invention is to provide a system for allowing a wireless device to retrieve a portion of or an entire email from one or a plurality of email systems. 
     It is yet another object of the invention to provide direct access to one specific or a plurality of specific email messages without having to retrieve or access other email messages. 
     Another object of the invention is to provide a messaging system that delivers messages or message notifications to a specific device, based on a variable such as: the “presence” of the user (i.e., whether the user has turned on his/her device), the location of the device, the device being accessed, the importance level of the message, the type of message, the time or date, the weather, a user action, or a user request. 
     It is still another object of the invention to provide automatic identification of a wireless mobile phone user or wireless email device and a mobile phone user&#39;s reply email message destination by utilizing a phone number or code. 
     It is yet another object of the invention to provide an improved method for memory management in a messaging device. 
     Other objects, features, and advantages of the present invention will become apparent with respect to the remainder of this document. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The accompanying drawings, which are incorporated in and form a part of the specification, illustrate preferred embodiments of the present invention and, together with the description, serve to explain the principles of the invention, and to enable a person skilled in the pertinent art to make and use the invention. In the drawings: 
         FIG. 1  is a block diagram of a paging transceiver according to a preferred embodiment of the invention, and a simplified block diagram of a user device according to a preferred embodiment of the present invention; 
         FIG. 2  is a more detailed block diagram of the transceiver in the paging transceiver of  FIG. 1 , and a more detailed block diagram of a user device according to a preferred embodiment of the present invention; 
         FIG. 3  is a block diagram of a communication system according to a preferred embodiment of the invention, and is a block diagram of a remote device according to a preferred embodiment of the present invention which is adapted to store voice messages and other information for access and management by, among other things, user devices such as those shown functionally in  FIGS. 1 and 2 ; 
         FIGS. 4A and 4B  are flow charts depicting an exemplary set-up routine for establishing communications between the system of  FIG. 3  and the transceiver of  FIG. 1 ; 
         FIG. 5  is a flow chart depicting a paging process; 
         FIG. 6  a flow chart depicting of process of notifying a paging transceiver of an unread message; 
         FIG. 7  is a flow chart depicting a process of receiving a page at the paging transceiver of  FIG. 1 ; 
         FIG. 8  is a flow chart depicting a process of selecting a function at the paging transceiver of  FIG. 1 , and is a schematic diagram for an interface according to a preferred embodiment of the present invention for accessing and managing messages on a plurality of platforms; 
         FIG. 9  is a generic flow chart depicting a selective process performed at the paging transceiver of  FIG. 1  for executing a desired function, and is flow diagram of a process according to a preferred embodiment of the present invention for initiating a communications session with a remote device and accessing and managing messages at the remote device and in the user&#39;s device; 
         FIG. 10  is a block diagram of a paging system having multiple systems for storing messages; and 
         FIG. 11  is a diagram of a data transmission for the system in  FIG. 10 . 
         FIG. 12  is a flow diagram of a process according to a preferred embodiment of the present invention for playing and/or retrieving messages. 
         FIG. 13  is a flow diagram for a process according to a preferred embodiment of the present invention for pausing while playing messages. 
         FIG. 14  is a flow diagram for a process according to a preferred embodiment of the present invention for erasing messages. 
         FIG. 15  is a flow diagram for a process according to a preferred embodiment of the present invention for saving messages. 
         FIG. 16  is a block diagram of a wireless messaging system. 
         FIGS. 17A and 17B  is a flowchart illustrating a process of replying to a message. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Reference will now be made in detail to preferred embodiments of the invention, non-limiting examples of which are illustrated in the accompanying drawings. With reference to  FIG. 1 , a paging transceiver  100  according to a preferred embodiment of the invention comprises an antenna  1 , a transceiver  2 , a user interface  3 , a controller  4 , and a memory  5 . The single antenna  1  is preferably used for both receiving and transmitting signals, although the paging transceiver  100  may comprise a separate antenna for transmitting signals and a separate antenna for receiving signals. 
     The transceiver  2  is connected to the antenna  1  and is for transmitting signals from the paging transceiver  100  and for receiving signals directed to the paging transceiver  100 . The signals that may be transmitted to, or received from, the paging transceiver  100  include, but are not limited to, such signals as selective call signals, command data signals, signals corresponding to a message, and information data signals. The transceiver  2  may comprise a transceiver found in two way pagers or mobile radios and preferably comprises a transceiver commonly used in a portable mobile radiotelephone. 
     The transceiver  2  is connected to the user interface  3 , which contains all necessary input and output devices. The user interface  3  includes a microphone, speaker, alert transducer, LED or LCD display, keypad, and necessary switches. The user interface  3  may also contain other types of input/output devices depending on the messaging application, such as a video display, camera, scanner, a printer, or a voice recognition device. The user interface  3  is not limited to these examples of user input/output devices but may comprise any input or output device which allows or assists communication between the user and the paging transceiver  100 . 
     The transceiver  2  is connected to, and communicates with, the controller  4 , which preferably comprises a digital signal processor (DSP)  4 . The memory  5  is connected to the DSP  4  and is for storing messages or other types of information. The memory  5  may comprise static RAM, Dynamic RAM, Flash RAM, or any type of memory suitable for storing messages and allowing the retrieval of the messages. The amount of the memory  5  is preferably at least 4 MB for voice or text applications, although it may consist of a greater or lesser amount depending upon the specific message type application. 
       FIG. 1  shows a basic functional block diagram of a paging transceiver  100  according to a preferred embodiment of the present invention. A transmit/receive antenna  1  is connected to transceiver  2  for transmitting and receiving signals such as selective call signals, command data signals and information data signals via conventional radio frequency link. Transceiver  2  may be of any conventional design such as those utilized in two way pagers, mobile radios or portable cellular telephones and similar devices, products or equipment. Transceiver  2  is coupled to a user interface  3  which contains appropriate input and output devices including, for example, a microphone speaker, alert transducer, LED or LCD display, keypad and necessary switches. The user interface  3  may also contain other types of input/output devices depending on the messaging application such as video display, camera, scanner, printer or voice recognition devices, and others. The user interface  3  of the present invention may be of any sort which allows the user to communicate with the transceiver  2 . The transceiver  2  is coupled to and communicates with the digital signal processor (DSP)  4 . DSP&#39;s are conventional in portable cellular transceivers for signal processing purposes. A message memory  5  is coupled to DSP  4  for storing messages. Message memory  5  may be static RAM, Dynamic RAM, Flash RAM, or any type of memory suitable for the messages to be stored and addressed in a manner that allows them to be accessed and managed. 
       FIG. 2  shows transceiver  2  in greater detail. An antenna interface  20 , for example a conventional cellular duplexer, antenna transmit/receive switch or other device or component or system may be utilized to provide signal isolation and otherwise couple the antenna to the transceiver. Optionally two antennas may be utilized in order to eliminate the antenna interface 
       20 . Antenna interface  20  couples received signals to receiver  22  of receive section  21 . Receive frequency synthesizer  23  couples to receiver  22  for selecting the receive frequency. Transmit section  24  comprises a transmitter  25  coupled to antenna interface  20  for transmitting signals using antenna  1 . A transmit frequency synthesizer  26  is connected to transmitter  25  for selecting the transmit frequency. A processor chip set or CPU  27  comprises all necessary RAM and ROM memory, signal and data switching circuitry, signal processing circuitry, I-O Ports including all necessary program instructions and stored options commonly utilized in portable cellular telephones. Cellular telephone program instructions and necessary chip set circuitry are conventional and may be obtained from a variety of suppliers. 
     CPU  27 , DSP  4  and other components of devices and systems according to the present invention, if desired, individually and/or collectively contain program instructions and algorithms necessary to process, store and reproduce and otherwise access and manage messages such as voice messages or other messages in connection with the present invention. These instructions and algorithms may, for instance, be stored within a particular DSP for application specific purposes, such as video processing and storage, speech processing and storage, modem signal processing and numerous other types of signal processing applications. Optionally, DSP  4  may be an alternative hardware device such as coded or digital to analog/analog to digital conversion circuit or other type of modulator-demodulator including memory interface circuitry coupled to message memory  5  for reading and writing and other accessing and management of messages. 
     The transceiver  2 , as shown in more detail in  FIG. 2 , includes an antenna interface  20  connected to the antenna  1 . The antenna interface  20  directs signals received from antenna  1  to a receiver section  21  of the paging transceiver  100  and directs signals transmitted from a transmit section  24  to the antenna  1 . The antenna interface  20  is preferably a duplexer, however an antenna switch or other device may be utilized to provide signal isolation between the receiver and transmitter sections  21  and  24 . Alternatively, if paging transceiver  100  includes two antennas  1  with one for transmitting signals and the other for receiving signals, the transceiver  2  would not require any type of antenna interface  20 . 
     The receive section  21  includes a receiver  22  and a receiver frequency synthesizer  23 . The receiver  22  is connected to the antenna  1  through antenna interface  20  and receives the signals directed to the paging transceiver  100 . The receiver frequency synthesizer  23 , based on an input from a processor  27 , selects the frequency at which the receiver  22  receives signals. The received signals are passed from the receiver  22  to the processor  27 . 
     The transmit section  24  includes a transmitter  25  for receiving signals from the processor  27 . The transmit section  24  also includes a transmitter frequency synthesizer  26  connected to the transmitter  25  which, based upon an input from the processor  27 , selects the transmit frequency for the transmitter  25 . The signals output by the transmitter  25  are supplied to the antenna interface  20  and then to the antenna  1 . 
     The processor  27  comprises a central processing unit (CPU) having internal memory and switching capabilities. The CPU  27 , for instance, comprises all necessary RAM and ROM memory, signal and data switching circuitry, signal processing circuitry, I-O Ports, and all standard program instructions and stored options commonly utilized in portable cellular telephones. The standard cellular telephone program instructions and CPU  27  may be obtained from a variety of suppliers. For instance, the instructions may be obtained from Wireless Link Inc. of Sunnyvale, Calif. and the CPU  27  from GEC Plessey Semiconductor, Inc. of Scotts Valley, Calif. 
     The DSP  4  includes necessary I-O and program memory and are commonly utilized in cellular telephones. Any suitable DSP may be used in the paging transceiver  100 . Alternatively, the controller  4  may comprise another type of electronic device, such as a codec or digital-to-analog/analog-to-digital conversion circuit or other type of modulator-demodulator including memory interface circuitry coupled to message memory  5  for reading and writing of messages. 
     The transceiver  2  also preferably includes a delay circuit  28 . The delay circuit  28  may comprise a timer which informs the processor  27  of when a period of time has expired. The timer, for instance, may expire at a certain time of day, week, or month, or may expire a fixed period of time after a triggering event, such as one hour after the event. The time at which the timer  28  expires is preferably programmable through the user interface  3  and through processor  27 . Additionally, the timer  28  preferably comprises a plurality of timers for notifying the processor  27  of when a plurality of different time periods have expired. Rather than a timer, the delay circuit  28  may alternatively operate to delay the occurrence of an event until a certain condition is satisfied. This condition, for instance, may be the strength of received signals or the receipt of a specified signal. The purpose of the timer  28  will become apparent from the description below. 
     With reference to  FIG. 3 , a system  30  according to a preferred embodiment of the invention is interconnected to a base station  34 , both of which are connected to the Public Switched Telephone Network (PSTN) or to other telephone company equipment  35 . The system  30  comprises a paging terminal controller  31  which may comprise a controller circuit and associated memory having a database of subscriber listings and corresponding selective call address fields. The paging terminal controller  31  communicates with storage and retrieval unit  32  and correlates messages with subscriber listings. The storage and retrieval unit  32  may comprise a CPU or control circuit, message information and program memory, memory interface circuitry and a DSP with appropriate operational code for storage and retrieval of the desired messages. The input/output controller  33  contains all necessary input and output circuitry such as encoders and decoders, modems and required routing and control circuitry for communicating with the paging terminal controller  31 , the storage and retrieval unit  32 , the PSTN  35 , and the base station  34 . 
       FIG. 3  shows a system  30  interconnected to a base station or remote unit  34 . Conventional telephone company or other telecommunications or PSTN equipment  35  communicates with the base station  34  and system  30  in conventional fashion. The system  30  can comprise a paging terminal controller  31  which may comprise a controller circuit and associated memory (not shown) having a database of subscriber listings and corresponding selective call address fields. The paging terminal controller  31  communicates with storage and retrieval unit  32  and correlates messages with subscriber listings. The storage and retrieval unit  32  may comprise appropriate processor or control circuitry, message information and program memory, memory interface circuitry and DSP capacity with appropriate operational code for storage and retrieval of the desired messages. The input/output controller  33  contains all necessary input and output circuitry such as encoders and decoders, modems and required routing and control circuitry (not shown) for communicating with the paging terminal controller  31 , the storage and retrieval unit  32 , telephone company equipment  35  and base station  34 . Such base stations and their components may be conventional. 
     A call setup routine  40  for establishing communication between the system  30  and base station  34  will now be described with reference to  FIGS. 4A and 4B . At step  41 , a connection, such as a telephone connection, is routed through the PSTN  35  or in the case of paging transceiver  100  the switch  36 , to the input/output controller  33 . The input/output controller  33  determines at step  42  whether the connection is with an automated signaling device or with a person. If the connection is with a person, then at step  48  the storage and retrieval unit  32  is activated to produce one or more voice responses during the call in order to guide the person throughout the process. 
     If, at step  42 , the input/output controller  33  determines that the call is from a device, such as a paging transceiver  100  or computer terminal, data is exchanged between the paging transceiver  100  and system  30  at step  43 . The type of data that may be exchanged includes, but is not limited to, the following types of data: identification data, command data, and information data. The data supplied from the PSTN  35  may also be exchanged at step  43  with this data including data for identifying the caller and subscriber, such as, for example, Caller ID and DNIS (Dialed Number Identification Service). Additionally, the data may be extracted from the base station  34 . For example, the location of the paging transceiver  100  may be determined from a home location registry (HLR) and the HLR data may be utilized by the system  30  in order to determine the location of the paging transceiver  100 , as opposed to having the paging transceiver  100  supply the location information to system  30 . 
     After data is exchanged at step  43 , the system  30  determines at step  44  whether an error occurred during the transmission between the system  30  and paging transceiver  100 . If an error did occur, then at step  47  the process ends and the paging transceiver  100  is informed of the error. The error is preferably presented to the user in the form of status information produced at the user interface  3 , such as with an alert tone or visual display on the LED or LCD display. An error may include, but is not limited to, the following errors: “system busy,” “wrong ID,” or “bill over due.” If no error is detected, as determined by the system  30  at step  44 , a function is enabled and executed at step  45 . The function, as will be described in greater detail below with reference to  FIG. 8 , may be selected by the user from a group of available functions. At step  46 , housekeeping functions are performed both at the paging transceiver  100  and at the system  30  and the call is terminated at step  47 . 
     If the call is from a person as determined at step  42 , then the caller is provided with a voice response at step  48  and, with reference to  FIG. 4B , the caller is then verbally prompted at step  49  to enter information. At step  50 , the caller sends data to the system  30 , such as by pressing the telephone keypad to generate DTMF tones. The data that may be sent by the caller includes, but is not limited to, ID code, pass code, mail box number, and subscriber number. The system  30  may respond to voice commands from a caller by utilizing a readily available voice recognition system, such as those presently in use by the telephone company to except collect calls. At  51 , the system  30  determines whether an error has occurred. If an error is detected, the caller may be given an opportunity to correct the error or, as shown, the process may end at step  56 . If no error was detected by the system  30  at step  51 , a message, such as a voice message, is recorded and stored in the storage and retrieval unit  32  at step  52 . At step  53 , the system  30  determines whether a return receipt or a reply message is requested. If a return receipt or reply message is requested, the return address is entered by the caller or optionally issued by the system  30  and is stored by the system  30  in the storage and retrieval unit  32  at step  54 . The system  30 , for instance, may detect the address signal of the incoming call and, by default, store this number as the return address. After the return address is stored at step  54  or if a return address is not requested, the stored message is cross referenced to selective call data corresponding to the intended paging transceiver  100  at step  55 . Also at step  55 , a flag is set in a transmission stack file at the paging terminal controller  31  for subsequently transmitting selective call signals representative of the selective call data to the targeted paging transceiver  100 . Housekeeping is performed by the system  30  and the call ends at step  56 . 
     The base station  34 , as shown in  FIG. 3 , comprises a switch  36 , a transceiver antenna  37 , and a transceiver base station  38 . In response to a received message, the system  30  passes control information to switch  36  for setting up a page call. The switch  36 , for instance, may be a mobile telephone switching office (MTSO) for interfacing to the transceiver base station  38 . In the send page mode, selective call signals having an address associated with the paging transceiver  100  are transmitted. The address may be an address code for a paging transceiver, a mobile telephone number (MIN) for a mobile radiotelephone, or type of identifying information for a communication device. 
     Command data and information data may also be communicated from the system  30  to the paging transceiver  100  through the base station  34 . The command data and information data shall hereinafter be referred to as CI data, examples of which include the following: paging transceiver location, forward message, retrieve message, reply to message, paging transceiver ID, message identifiers, retrieval instructions, save message, erase message, message type, message length, time/date message received, system  30  ID, system  30  location, message address, message location, battery life, message identifier, format code, compression type, message age, message priority, alert codes, energy saving commands, memory status, program data, provisioning data, acknowledgment data and requests, function codes, sender name, current time, number of messages, mailbox number, phone number, return address, alpha numeric short messages, general command requests, group calls, and signal strength. 
     The address and command data and information may be transmitted over any suitable communication system. For instance, the data may be communicated over a paging system, a cellular system having short message service capabilities, such as GSM-SMS, a Cellular Digital Packet Data (CDPD) system, Personal Communications Services, or any other type of mobile radiotelephone system or communication system. Furthermore, the paging transceiver  100  preferably is able to communicate over more than one system, such as with both a paging network and a mobile radiotelephone network. 
     With reference to  FIG. 5 , a flow diagram  60  for performing a page call is shown. At step  61 , the system  30  locates the current message flag from its transmission stack within paging terminal controller  31  and communicates with base station  34  for setting up a page call. The base station  34  transmits selective call signals and CI data to the targeted paging transceiver  100 . At step  62 , the system  30  determines whether an acknowledgment (Ack) was received from the paging transceiver  100  indicating that the page call was received. If an acknowledgment was not received, then at step  70  the system  30  determines whether an acknowledgment is a system  30  option. If an acknowledgment is required, then at step  71  the system  30  assigns the page call a priority in the transmission stack and eventually returns to step  61  for re-transmission. If the acknowledgment is received at step  62 , the system  30  sets an acknowledgment flag (Ack flag) corresponding to the stored message. 
     If an acknowledgment is not a system requirement, as determined at step  70 , or after posting the acknowledgment flag at step  63 , the system  30  sets a timer at step  64  and waits a period of time before proceeding to step  65 . At step  65 , the paging terminal controller  31  determines if the stored message has been read. If the message has been read, then at step  66  the system  30  posts a read flag in the subscriber data base to indicate that the message was delivered and read and at step  67  the process ends. 
     If, at step  65 , the message had not been read, then at step  68  the system  30  determines the priority of the message and proceeds to step  69 . If the priority is high, as determined at step  69 , then at step  61  the page call is returned to the transmission stack at the designated priority level for retransmission. If, on the other hand, the priority is not high as determined at step  69 , then the message has a low priority and the process ends at step  67 . 
     An alternate routine  80  for notifying a paging transceiver  100  that an unread message is waiting is shown in  FIG. 6 . At step  81 , the paging terminal controller  31  sorts through subscriber listings which have a corresponding unread and unnotified message in the storage and retrieval unit  32  and sends a page request to base station  34 . At step  82 , the switch  36  checks a home location registry (HLR) to determine the registered location and status of the remote paging transceiver  100 . A page call is processed by transmitting selective call signals from transceiver base station  37  at step  82 . If a page acknowledgment is desired for verification that the paging transceiver  100  recipient received the selective call signals, an Ack signal is manually or automatically transmitted from the paging transceiver  100  to base station  34  for storage in the subscriber database of paging terminal controller  31  at step  82 . 
     At step  83 , if an acknowledgment signal was received, a notified flag is set in the subscriber data base corresponding to the unread message stored in the storage and retrieval unit  32  and the paging process for the current unread message ends at step  84 . If at step  83  an acknowledgment signal was not received, the message is assigned a new priority and the process is subsequently repeated. Optionally, a plurality of priorities may be assigned to acknowledged and not acknowledged unread messages so that the paging transceiver  100  is sent a number of calls until the message is read by the subscriber. 
     In the preferred embodiment, the base station  34  is part of a mobile radiotelephone network and the paging transceiver  100  is paged over the designated paging channel or the control channels of the network. In addition to paging the paging transceiver  100 , the short messages or other data transmitted to the paging transceiver  100  is also preferably transmitted over the paging channel or control channels. Although the paging is preferably performed through a mobile radiotelephone network, the selective call signals may alternatively be routed to a paging system for transmitting an address code and CI data over an independent paging transmitter. In such a configuration, the paging transceiver  100  may be configured to have a separate paging receiver or transceiver compatible with the paging transmitter or paging transceiver. Since radio pager devices require much less energy than portable cellular telephones, a paging transceiver  100  configured with a low energy paging receiver would reduce energy required for receiving selective call signals and allow high energy circuitry of the paging transceiver  100  to be turned off until the user needs to retrieve or transmit messages. Other variations and modifications will be apparent to those skilled in the art. 
     A process  90  for receiving messages at a paging transceiver  100  is shown in  FIG. 7 . A selective call signal including an address is received by receive section  21  of the transceiver  100  at step  91 . At step  92 , the demodulated signal is processed by the CPU  27  to compare the received address with an address code stored in the CPU  27  memory. If the received address code does not match the stored address, flow returns to step  91  and the transceiver  100  continues to monitor transmissions for its address. When the address corresponds to the pre-stored address code, as determined at step  92 , the CPU  27  stores and processes any corresponding received CI data at step  93 . 
     Next, at step  94 , the CPU  27  determines if an acknowledgment transmission is required by the paging transceiver  100 . The CPU  27  may always enable an acknowledgment in order to confirm at the system  30  or base station  34  that the selective call signals were received by the targeted paging transceiver  100 . Alternatively, the CPU  27  may never enable an acknowledgment from the transceiver  100 , which is useful in explosive environments where transmissions are dangerous and in environments where a reply from the paging transceiver  100  may cause harmful interference to other electronic equipment. The CPU  27  may, as another option, enable an acknowledgment only when acknowledgment data is contained within the received CI data, such as with a remote request. Finally, the CPU  27  may enable an acknowledgment in response to a user-enabled command. 
     Returning to step  94 , if the paging transceiver  100  allows for an acknowledgment then at step  95  the CPU  27  determines whether the acknowledgment is required or if the acknowledgment is a user option. If the acknowledgment is required to be automatic, then an acknowledgment flag is set at step  97 . If, on the other hand, the acknowledgment is not automatic but rather optional, then at step  96  the CPU  27  determines whether an acknowledgment has been enabled. If the acknowledgment has been enabled, then the acknowledgment flag is set in step  97 . 
     At step  98 , the CPU  27  determines whether short messages may be transmitted. Short messages may include CI data or any type of short coded message which was pre-stored by the user in the paging transceiver  100 . If short messages are enabled, at step  99  the CPU  27  sets the short message flag. At step  100 , the paging transceiver  100  transmits all flagged data, including CI data, to the base station  34  for processing by the system  30 . The CPU  27  generates status information corresponding to received CI data and passes any necessary user status information to the user interface  3  for visual and/or audible reception by the user. For example the user may hear an alert beep, feel an alert vibration, view an LCD indicating the number of unread messages, view an animated graphic display, hear a synthesized voice indicating that an urgent message is waiting, or receive other types of indications. At step  101 , the CPU  27  performs house keeping functions and the routine ends. 
       FIG. 8  depicts a user function flow diagram  110  for user selectable function requests at the paging transceiver  100 . At step  111 , the user selects a function to be performed from available functions  112  to  117 . These functions are exemplary functions that may be available and additional functions may exist. One or more of these functions are preferably selected through the user interface  3 . One or more messages may be selected by the user to be forwarded to one or a plurality of addresses or recipients at step  112 . Items such as messages and send message lists may be selected by scrolling through the message number or name. The selected messages for forwarding may reside at the paging transceiver  100  or at the system  30 . The user may also select the function of saving a selected message at step  113 . At step  114 , selected messages are retrieved for reproduction and/or storage. At step  115 , messages may be sent to one or a plurality of recipients, such as to another paging transceiver  100 . At step  116 , the selected message may be erased and at step  117 , a reply may be sent to the originator of a selected message. With any of the functions selected at steps  112  to  117 , the system  30  may act upon the entire information or, alternatively, may instead operate on only the message identifier. For instance, if the user selected the desired action of forwarding a message, the system  30  may send the entire message to a designated recipient or may instead send just the message identifier. 
       FIG. 8  is a schematic diagram for a preferred embodiment of an interface according to the present invention for user selectable function requests at the paging transceiver  100  in order to access and manage messages. At step  111 , the user selects a function to be performed. Flow proceeds to the desired function selected. At step  112 , messages may be selected by the user to be forwarded to one or a plurality of addresses. Items such as messages and send message lists may be selected by scrolling through the message number or name. Selected messages may reside at the paging transceiver  100  or at the system  30 . At step  113 , a selected message may be saved. At step  114 , selected messages are retrieved for reproduction and/or storage. At step  115 , messages may be sent to another or a plurality or recipients such as another paging transceiver  100 . At step  116 , the selected message may be erased. At step  117 , a reply may be sent to the originator of a selected message. 
       FIG. 9  shows a flow diagram illustrating one version of process flow to implement functions  112 - 117  shown in  FIG. 4 . When forward message (step  112 ) is selected, flow proceeds to step  131 , where CPU  27  reads information pertaining to the message or plurality of messages selected by the user to be forwarded. The information may include a message identifier, location data, message length, message type, destination addresses, or other so-called CI type data. Flow proceeds to step  132  where it is determined whether the message can be forwarded without communicating with the system  30 . If so, the appropriate function is performed at step  133  to handle the messages as desired by the user. If not, flow proceeds to step  134  where CPU  27  determines if a call is in progress. If a call is in progress flow proceeds to step  135  where CI data is exchanged with the system  30  for forwarding messages. If the messages to be forwarded are located at the system  30 , the messages are simply flagged for forwarding to the appropriate addresses, step  136 , and confirmation is communicated to the paging transceiver  100 . If the message is not located at system  30 , it is transmitted from paging transceiver  100  to system  30  at step  136 . The process ends at step  140 . If at step  134 , it is determined that a call is not in progress, the user is asked if the message should be forwarded now, step  137 . If the user selects yes, a call is established with system  30 , step  139 , and flow continues as previously described. If no, CPU  27  retains the forwarding information in memory for forwarding the message during a subsequent call with system  30  and process ends, step  140 . 
     The paging transceiver  100  and system  30  may exchange status information during messaging calls initiated by the paging transceiver  100  or by selective call (i.e. page calls) initiated by the system  30 . The status information may contain information corresponding to messages stored within the paging transceiver  100  or within the system  30 . For example, if the system  30  erases a message that has resided in its memory for too long a period of time (i.e. an unsaved, read message) the system  30  may inform the paging transceiver  100  that the message no longer exists. If the message identifier stored in the paging transceiver  100  no longer corresponds to a message stored in the system  30  or the paging transceiver  100 , CPU  27  can remove the identifier for the no longer existing message. 
     In operation, the user selects a message or messages to be forwarded. The user also selects a recipient. If the message resides at the system  30 , it is simply forwarded to the addressed recipient. If the message is located in the paging transceiver  100  it is first transmitted to the system  30  before it can be forwarded to the intended recipient. In order to conserve time and resources, the system  30  will preferably not accept receipt of a message from the paging transceiver  100  if the same message already exists at the system  30 . The system  30  will simply perform the required function with the already present duplicate message. 
     Returning now to  FIG. 9 , if a save message function  113  is selected flow proceeds to step  131 , where the message identifier to be saved is read by CPU  27  and flow proceeds to step  132 , where CPU  27  determines if the message identified selected corresponds to a message already stored in message memory  5  and if the selected function can be processed off line. If yes, flow proceeds to step  133 , where a save message flag is set by CPU  27  in order to protect the message stored in message memory  54  from being over written and the process ends, step  140 . If at step  132 , it is determined that the message is not stored at the paging transceiver  100 , flow proceeds to step  134 , where a determination is made to see if a call is in progress. If a messaging call is in progress, CI data instructing the system  30  to save the message is sent. System  30  flags the stored message and sends a message saved acknowledgment or confirmation signal (Ack) to the paging transceiver  100 , step  136 . The CPU  27  converts the Ack to status information and informs the user that the message is saved at the system  30 . The process ends at step  140 . If at step  134 , it is determined that the paging transceiver  100  is not currently in communication with the system  30 , CPU  27  flags the message identifier for saving and the user is asked if the call should be made now, step  137 . If no, step  138 , the flag is kept for transmission to system  30  at a later time such as during a selective call to the paging transceiver  100  or during a messaging call to system  30 . If yes, flow proceeds to step  139  where a call is set up for transmitting the save flag and CI data as previously described. 
     Returning now to function  114  of  FIG. 9 , if the retrieve message function is selected, flow proceeds to step  131  where message identifiers corresponding to messages to be returned are read from CPU  27  memory for retrieving the message. Additionally, CPU  27  may read message location information, system ID information, address information, message length information, message type information and the like as previously described. Flow proceeds to step  132 , where CPU  27  determines where the message is located and if a call to system  30  is required. If the message is stored in message memory  5  of  FIG. 1 , flow proceeds to step  133 , where the message is retrieved. The message may be an audio message, visual message or electronic signal for transferring to another device. At step  132 , if the message does not reside in message memory  5 , CPU  27  determines that a call is required to retrieve the message and flow proceeds to step  134 , where it is determined if a call is in progress. If a call is in progress, flow proceeds to step  135  where CI data is exchanged such as which messages to retrieve, message length, message type, message identifier and the like. Flow proceeds to step  136  where the message is retrieved and simultaneously stored in message memory  5  by DSP  4  of  FIG. 1 . The appropriate status information corresponding to the message is stored in CPU  27  memory and the process ends. If at step  134  a call is not in progress, the user is asked if the call should be made now or if during another call, step  137 . Flow proceeds to step  138  where if the user chooses to place the call now then flow proceeds to step  139  and the call is processed. If the user chooses to delay the call until another session, the message is left flagged for retrieval at the next session and the process ends, step  140 . It should be noted that when the user chooses to postpone the call at step  138 , a timer  141  may be inserted so that the message may be retrieved at a desired time or a retrieval instruction may be sent from system  30  to paging transceiver  100  for causing the paging transceiver  100  to automatically retrieve a message or plurality of messages at a time designated by system  30 . For example, it may be desirable to have emergency weather information automatically retrieved during night time hours when telephone line charges and air time charges are less. The above described options may also be utilized for forwarding messages, erasing messages, saving messages, sending messages and replying to messages as will be shown in more detail hereinafter. 
     Referring now to the send message function  115  of  FIG. 9 : In order to send a message, the message must typically first be stored at the paging transceiver  100  or the system  30 . The process of storing or recording messages is conventional. It is only necessary that the stored message be identified, addressed to a recipient and properly identified in accordance with the description of the present invention. Examples of these devices are described in U.S. Pat. No. 4,602,129 to Matthew, et al., (which is incorporated herein by this reference) and U.S. Reissue Pat. No. 34,976 to Helferich, et al. (which, together with its underlying patent, has been incorporated by reference above). System  30  and paging transceiver of the present invention can be configured to record, store and retrieve a plurality of different types of messages as previously described depending on the application required. Returning to send message function  115 , when send message function  115  is selected, flow proceeds to step  131  where the selected message to be sent is identified and cross referenced to the selected recipient address information. Flow proceeds to step  132  and continues through the process in the same manner as forwarding a message, function  112 . The message to be sent may reside in the paging transceiver  100  or the system  30 . If the message resides in the system  30  and the paging transceiver  100 , the message in the system  30  corresponding to the CPU  27  message identifier will be sent in order to conserve time. If the message does not reside in system  30 , the message will be sent from the paging transceiver  100  to the system  30 . If the message is to be sent from the paging transceiver  100 , it may be a pre stored message or alternatively, the message may be transmitted to system  30  by paging transceiver  100  in real time during a call session between system  30  and paging transceiver  100 . 
     Referring now to erase message function  116  of  FIG. 9 , the erase message function allows a user to erase messages stored at the system  30  or at the paging transceiver  100  depending on the mode of operation. Given that a message may be erased without erasing the message identifier, if a message is erased at the paging transceiver and the identifier still exists, the message can be retrieved from the system  30 . In order to remove a message identifier at the paging transceiver  100 , the message must be erased at the system  30 . At step  131 , the selected message to be erased is identified and the user is asked if the selected message in the paging transceiver is to be erased or if both copies of the message are to be erased. If the local message only is selected to be erased, the message identification information is retained and flow proceeds to step  133  where the message stored in memory  5  of  FIG. 1  is flagged for erasure or overwriting. In other words, the message still exists but may be over written by another message when memory space is required. The message may be retrieved from message memory until it is over written. If at step  132 , a decision was made to erase both copies of the message, flow proceeds to step  134  where CPU  27  determines if a call is in progress. If yes, flow proceeds to step  135 , where CI data is exchanged instructing system  30  to erase the message. Flow proceeds to step  131  where system  30  transmits an Ack that the message was erased, CPU  27  flags the local message for erasure, the identifier is removed and both copies of the message and the identifiers are erased. If at step  134 , it is determined that a call is not in progress, flow proceeds to step  137 , where the local message is erased and the user is asked if the system  30  copy of the message needs to be erased now. If yes, flow proceeds to step  139 , the call is established and the process continues as previously described. If no, the necessary flags are set for erasing the remote message during the next communication with system  30 . Again, timer option  141  may be utilized for a timed erase of the message stored at system  30 . 
     Referring now to message reply function  117  of  FIG. 9 , the reply message function  116  is for sending a reply to an already received message. A reply message utilizes the same process as a send message except that a return address is already correlated to the message designated for reply. During send message function  115  the user is required to select an address or destination for the message to be sent. In other words, the user must know the destination or address in advance. Message reply function  117  does not require that the user know the address of the recipient because the message being replied to has a corresponding return address. Just like send message function  115 , a reply message may be sent in real time or it may be prerecorded and stored in the paging transceiver  100  for transmission to system  30 . Additionally, the replay transmission may be delayed for a set period of time as previously described. 
     The common user interface of the present invention serves to control functions at the paging transceiver  100  and/or corresponding functions of system  30 , (i.e. a remote device), depending on the location of a message and the communications status of the paging transceiver  100 . 
       FIG. 9  depicts processing performed by the paging transceiver  100  in response to the selection of any one of the functions  112  to  117  shown in  FIG. 8 . At step  131 , the function is identified by the CPU  27  and other processing occurs prior to step  132  where the CPU  27  determines whether a call is required. If a call is not required to perform the function, then at step  133  the CPU  27  performs the requested function and the process ends at step  140 . 
     If, on the other hand, a call is required, then at step  134  the CPU  27  next determines whether a call is already in progress. If a call is in progress, the CPU  27  exchanges data with the system  30  and base station  34  at step  135  and the function is performed or executed at step  136 . The data that is exchanged at step  135  includes a request signal that is sent from the paging transceiver  100  to the system  30  specifying the desired action and the particular information or message. If a call is not in progress, then at step  137  the CPU  27  preferably asks the user if a call should be made and receives the user&#39;s feedback at step  138 . If the user elects not to call, then a delay occurs at step  141  with delay circuit  28 . 
     As discussed above, the delay circuit  28  may be a timer which expires at a set time, such as at 1:00 a.m., when traffic and costs are low or may expire after a period of time, such as 1 hour. The set time or the period of time may be programmed by the user or may be determined by default values. Additionally, the delay circuit  28  may operate to delay operation until the signal strength is above a certain threshold. The delay circuit  28 , in this example, may therefore comprise a level detector and a comparator circuit for comparing the signal strength to the threshold level. The delay circuit  28  would therefore advantageously delay the paging transceiver  100  from initiating communication until signal strength is sufficiently high. Moreover, the delay circuit  28  may alternatively comprise a communication monitor circuit for determining when the paging transceiver  100  is communicating before performing a function. Also, the delay circuit  28  may detect transmissions and trigger a certain event in response to a received communication. As an example, if the paging transceiver  100  receives a certain type of message or a message from a particular source or individual, the paging transceiver  100  may automatically perform a programmed action. The paging transceiver  100  would therefore be able, for instance, to automatically forward all messages received from one recipient to a designated person. 
     After the timer  28  is triggered or if the user decides to call now, then at step  139  the CPU  27  sets up a call to the base station  34 . Once a call is established, then processing proceeds to step  135  for the exchange of data and then to step  136  for the performance or execution of the function. At step  140 , the process ends. The process shown in  FIG. 9  is not limited to the performance of a single function but also represents the processing if the user selects a number of functions. For example, the user may select the functions of retrieving a message at step  114  and forwarding a message at step  112  and these functions may be performed in unison with each other or sequentially one after the other. 
     The paging transceiver  100  and system  30  may exchange status information during messaging calls initiated by the paging transceiver  100  or by selective call, such as page calls, initiated by the system  30 . The status information may contain information corresponding to messages stored within the paging transceiver  100  or within the system  30 . For example, if the system  30  erases a message that has resided in its memory for too long a period of time, such as an unsaved, read message, the system  30  may inform the paging transceiver  100  that the message no longer exists. If the message identifier stored in the paging transceiver  100  no longer corresponds to a message stored in the system  30  or in the paging transceiver  100 , the CPU  27  removes the identifier for the no-longer existing message. 
     When the forward message function  112  is selected, flow proceeds to step  131  where the CPU  27  reads information pertaining to the message or plurality of messages selected by the user to be forwarded. The information may include a message identifier, location data, message length, message type, destination addresses, or other CI type data as previously described. At step  132 , the CPU  27  determines whether the message cannot be forwarded without communicating with the system  30 . At step  134 , the CPU  27  determines if a call is in progress. If a call is in progress, CI data is exchanged at step  135  with the system  30  for forwarding messages. If the messages to be forwarded are located at the system  30 , the messages are simply flagged for forwarding to the appropriate addresses. At step  136 , the messages are forwarded and confirmation is communicated to the paging transceiver  100 . If the message is not located at system  30 , the message is transmitted from the paging transceiver  100  to system  30  at step  136  and the process ends at step  140 . If at step  134 , it is determined that a call is not in progress, the user is asked if the message should be forwarded now at step  137 . If at step  138  the user selects yes, a call is established with system  30  at step  139  and flow continues as previously described. If at step  138  the user responds that a call should not be made, the CPU  27  keeps the forwarding information in memory for forwarding the message during a subsequent call with system  30  and a delay occurs at step  141  with delay circuit  28 , as described above. After the delay, a call is established with system  30  at step  139  and flow continues as previously described. The process ends at step  140 . 
     In operation, the user selects a message or messages to be forwarded and also selects a recipient for receiving the message. If the message resides at the system  30 , the message is simply forwarded to the addressed recipient. If the message is located in the paging transceiver  100 , the message is first transmitted to the system  30  at step  135  before it can be forwarded to the intended recipient. In order to conserve time, the system  30  will not accept receipt of a message from the paging transceiver  100  if the same message already exists at the system  30 . The system  30  will simply perform the required function with the already present duplicate message. 
     If the function selected is the save message function  113 , then at step  131  the message identifier to be saved is read by CPU  27 . At step  132 , the CPU  27  determines if the message identifier selected corresponds to a message already stored in message memory  5  and if the selected function can be processed off-line. If yes, at step  133  the CPU  27  sets a save message flag in order to protect the message stored in message memory  5  from being over-written and the process ends at step  140 . 
     If at step  132  the CPU  27  determines that the message is not stored at the paging transceiver  100 , then at step  134  the CPU  27  determines whether a call is in progress. If a messaging call is in progress, CI data instructing the system  30  to save the message is sent. The system  30  flags the stored message and sends a message saved acknowledgment to the paging transceiver  100  at step  136 . The CPU  27  converts the acknowledgment to status information and informs the user that the message is saved at the system  30  and the process ends at step  140 . If at step  134 , it is determined that the paging transceiver  100  is not currently in communication with the system  30 , the CPU  27  flags the message identifier for saving and the user is asked if the call should be made now at step  137 . If no, at step  138  the flag is kept for transmission to system  30  at a later time. A delay occurs at step  141  with delay circuit  28  as described above. After the delay, a call is established with system  30  at step  139  and flow continues as previously described. Transmission to system  30  may also take place at a later time, such as during a selective call to the paging transceiver  100  or during a messaging call to system  30 . If yes, then the CPU  27  sets up a call at step  139  for transmitting the save flag and CI data as previously described. 
     When the retrieve message function is selected at  114 , then at step  131  the message identifiers corresponding to messages to be returned are read from the CPU  27  memory for retrieving the message. Additionally, the CPU  27  may read message location information, system ID information, address information, message length information, message type information and/or as previously described. At step  132 , the CPU  27  determines the location of the message and determines if a call to system  30  is required. If the message is stored in message memory  5 , then at step  133  the CPU  27  retrieves the message. The message, for instance, may be an audio message, visual message, text message, or electronic signal intended to be transferred to another device. 
     At step  132 , if the message does not reside in message memory  5 , the CPU  27  determines that a call is required to retrieve the message and, at step  134 , determines if a call is in progress. If a call is in progress, CI data, such as which messages to retrieve, message length, message type, and message identifier, is exchanged at step  135 . At step  136 , the message is retrieved and simultaneously stored in message memory  5  by the DSP  4 . The appropriate status information corresponding to the message is stored by the CPU  27  in its memory and the process ends at step  140 . If at step  134  a call is not in progress, the user is asked if the call should be made now or if during another call at step  137 . At step  138 , if the user chooses to place the call, the call at step  141  is set up at  139 . If the user chooses to delay the call at step  141  until another session or some later time, the message is left flagged for retrieval at the next session or some later time and the process ends at step  140 . With the timer  28 , the message may be retrieved at a chosen time or a retrieval instruction may be sent from system  30  to paging transceiver  100  for causing the paging transceiver  100  to automatically retrieve a message or plurality of messages at a time designated by system  30 . For example it may be desirable to have emergency weather information automatically retrieved during night-time hours when telephone line charges and air time charges are less expensive. The above described options may also be utilized for forwarding messages, erasing messages, saving messages, sending messages, and replying to messages as will be shown in more detail hereinafter. 
     With the send message function  115 , in order to send a message, the message must first be stored at the paging transceiver  100  or at the system  30 . The process of storing or recording messages is well known to those of ordinary skill in the art and accordingly will not be described in further detail. Examples of these devices are described in U.S. Pat. No. 4,602,129 to Matthew, et al., titled “Electronic Audio Communications System With Versatile Message Delivery,” and in U.S. Reissued Pat. No. Re. 34,976 to Helferich et al, titled “Analog/Digital Voice Storage Cellular Telephone,” both of which are incorporated herein by reference. The system  30  and paging transceiver  100  can record, store and retrieve a plurality of different types of messages as previously described depending on the application required. 
     If the send message function  115  is selected, the CPU  27  identifies the message to be sent and cross references it to the selected recipient address information. At step  132 , the CPU  27  determines whether a call is required. The subsequent processing of sending a message should be apparent from the description above for forwarding a message and accordingly will not be duplicated in order to simplify description of the invention. The message to be sent may reside in the paging transceiver  100  or in the system  30 . If the message resides in the system  30  and in the paging transceiver  100 , the message in the system  30  corresponding to the CPU  27  message identifier will be sent in order to conserve air time. If the message does not reside in system  30 , the message will be sent from the paging transceiver  100  to the system  30 . If the message is to be sent from the paging transceiver  100 , the message may be a pre-stored message or alternatively, the message may be transmitted to system  30  by paging transceiver  100  in real time during a call session between system  30  and paging transceiver  100 . 
     If the erase message is selected at step  116 , the erase message function allows a user to erase messages stored at the system  30  or at the paging transceiver  100  depending on the mode of operation. A message may be erased at a paging transceiver  100  without erasing the message identifier. If a message is erased at the paging transceiver  100  and the identifier still exists in message memory  5 , the message can be retrieved from the system  30 . In order to remove a message identifier at the paging transceiver  100 , the message must be erased at the system  30 . This feature causes the user to manage the messages at the platform, thereby conserving memory space at the storage and retrieval unit  32 . At step  131 , the selected message to be erased is identified and the user is asked if the selected message in the paging transceiver is to be erased or if both copies of the message are to be erased. If the local message only is selected to be erased, the message identification information is kept and at step  133  the CPU  27  flags the message stored in memory  5  for erasure or overwriting. In other words, the message still exists but may be over-written by another message when memory space is required and, until then, may be retrieved from message memory  5 . If at step  132  a decision was made to erase both copies of the message, then at step  134  the CPU  27  determines if a call is in progress. If yes, at step  135  the CI data is exchanged instructing system  30  to erase the message. At step  131 , the system  30  transmits an acknowledgment that the message was erased, the CPU  27  flags the local message for erasure, the identifier is removed and both copies of the message and the identifiers are erased. 
     If at step  134  the CPU  27  determines that a call is not in progress, the CPU  27  at step  137  erases the local message and the user is asked if the system  30  copy of the message needs to be erased now. If the user responds yes, at step  138  the call is established at step  139  and the process continues as previously described. If the user responds no at step  138 , the necessary flags are set for erasing the remote message during the next communication with system  30  after the delay of step  141  and the timer  28  is activated. The timer  28  may be utilized for a timed erase of the message stored at system  30 . 
     The message reply function  117  is for sending a reply to an already received message. A reply message utilizes the same process as the send message function except that a return address is already correlated to the message targeted for a reply. During the send message function  115 , the user is required to select an address or destination for the message to be sent. In other words, the user must know the destination or address in advance. The message reply function  117  does not require that the user know the address of the recipient because the message being replied to has a corresponding return address. As with the send message function  115 , a reply message may be sent in real time or it may be prerecorded and stored in the paging transceiver  100  for transmission to system  30 . Additionally, the reply transmission may be delayed for a set period of time as previously described with timer  28 . 
     In summary, as discussed above with reference to  FIGS. 5 and 6 , the system  30  does not transmit the entire message to the paging transceiver  100  but rather notifies the user that a message is waiting. The paging transceiver  100 , as discussed above with reference to  FIG. 7 , stores data associated with the page and possibly a short message. The user can then select a desired one of plurality of available functions, such as those shown in  FIG. 8 , and the paging transceiver  100  will process the request in accordance with  FIG. 9 . 
     With the system  30  and paging transceiver  100 , the paging transceiver  100  can notify a user of a message without receiving the entire message. The user can then decide to act upon the message at a time convenient to the user. Rather than receiving the message with the alert, as occurs with conventional paging receivers, the user can control the time when he or she wants to receive a message and may even decide not to retrieve the message. After the user has been notified, the user can then control the paging transceiver  100  to retrieve the message from the system  30 , to save the message at either the system  30  or paging transceiver  100 , to forward the message to an indicated recipient, to reply to the message, or to erase the message from the paging transceiver  100  or from the system  30  With paging transceiver  100 , the user can position the paging transceiver in a desired location before initiating communication with the system  30 . Thus, if the user is paged by system  30  while the user is in a subway, basement, or on an airplane, the user can postpone the delivery of the message until the paging transceiver  100  is in a better location to receive and reply to the message. Similarly, the user may be in an explosive environment or near sensitive electronic equipment and may postpone delivery of the message and a reply from the paging transceiver  100  until the user is out of the explosive environment or far enough away from the sensitive electronic equipment. The paging transceiver  100  and system  30  therefore give the user control over the messages stored in the system  30 . 
     The paging transceiver  100  and system  30  conserve both valuable air time and also paging transceiver message memory  5 . The system  30  does not automatically deliver each message to the intended paging transceiver  100  but instead allows the user to exercise control over the message. Since a message may be many bytes in length, perhaps kilobytes, megabytes, or even greater, the benefit to the system  30  and to the base station  34  in not having to transmit each message can be quite substantial. Also, since each message is not automatically delivered to the paging transceiver  100 , the paging transceiver  100  does not become overloaded with messages and instead the user can choose to act on selective messages, such as by retrieving only certain messages. The user, additionally, may decide not to act on any of the messages through base station  34  and may call the system  30  through the PSTN  35 , thereby bypassing the base station  34  and its associated charges and expenses. 
     The paging transceiver  100  and system  30  are not limited to voice messages in a paging system. Rather, the paging transceiver  100  and system  30  may operate with any type of message or information, including, but not limited to numeric messages, alphanumeric messages, voice or other audio messages, video messages, graphics or even data. The paging transceiver  100  may be a separate paging transceiver, may be integral with a mobile radiotelephone, or may be incorporated into other devices. 
     For instance, the paging transceiver  100  may be integrated into a portable radio, CD, or tape player. The paging transceiver  100  could receive messages from system  30  which indicate portions of songs that may be sampled by the user. The user may browse through a listing of available music and select a desired song. The paging transceiver  100  then communicates with the system  30  to retrieve the selected song and the user can then play the song at the paging transceiver  100 . 
     As another example, the messages may be video messages which the user can browse through and select only desired messages. The paging transceiver  100  may be integral with a television set and the video messages may be promotions for new movies or shows. Alternatively, the paging transceiver  100  may be integral with a game console and the video messages may be clips of new games that are available with that game console. Other applications for the paging transceiver  100  and system  30  will be apparent to those skilled in the art. 
     The information or message available to a paging transceiver  100  need not be static but instead may be dynamic. In other words, when a paging transceiver  100  is alerted that information is available, the information may be updated or otherwise change from the time that the user was alerted. As an example, the user may receive a weather alert and by the time the user decides to receive the information the information would be updated to reflect current weather conditions. The identifier for the information therefore does not limit the content that may be stored as the information available to the user. 
     The system  30  is not limited to transmitting only one alert at a time to one paging transceiver  100 . Instead, the system  30  may send a plurality of alerts to a single paging transceiver  100  and each of those alerts may be broadcast to a plurality of paging transceivers  100 . For instance, the system  30  may broadcast information to a plurality of transceivers  100  that share a common set of numbers within their mobile identification numbers. If the system  30  sends a plurality of alerts to a paging transceiver  100 , these alerts may be displayed by the user interface  3  and the user can scroll through and act upon the messages as desired. 
     As discussed above, the system  30  and paging transceiver  100  allows information to be remotely acted upon by the paging transceiver  100 . The system  30 , however, also allows users access to their information via conventional ways, such as the PSTN  35 . Therefore, a user may receive the alert with a paging transceiver  100  and decide to call in through the PSTN  35  to listen or otherwise act upon the message. The system  30  preferably is connected to the Internet whereby users can also gain access and act upon their information via the Internet. 
     The paging transceiver  100  preferably alerts the user both when a message identifier signal has been received and when complete messages have been received. The alerts may comprise any suitable indication to inform the user that the paging transceiver  100  has received a communication, such as a tone, vibration, or visual display. The alerts for a received identifier and for a received message are preferably different so as to allow a user to easily differentiate between the two communications. 
     The example provided in  FIG. 3  was a single system  30  for storing messages on behalf of a plurality of paging transceivers  100 . The invention, however, may include any number of systems  30  for storing messages with each system  30  storing information for a transceiver  100  being considered a content provider. For instance, as shown in  FIG. 10 , a messaging system  200  may comprise a plurality of systems  30  connected to the PSTN  35  with system  30 A being associated with base station  34 A and transceiver antenna  37 A and system  30 B being associated with base station  34 B and transceiver antenna  37 B. Although three systems  30  are shown, the system  200  may include any number of systems  30  and, although two base stations  34  are shown, each system  30  may be associated with a base station  34  and transceiver antenna  37  or only one of the systems  30  may be associated with a base station  34  and transceiver antenna  37 . Furthermore, each system  30  need not include a paging terminal controller  31  or a storage unit  32 . System  30 C, for instance, may include a storage and retrieval unit  32  and input/output controller  33  but not a paging terminal controller  31  and may page the paging transceiver  100  through the paging terminal controller  31  in system  30 A. Conversely, a system  30 , such as system  30 A, may include a paging terminal controller  31  and an input/output controller  33  but not a storage and retrieval unit  32 . Further, the input/output controller  33  need not be a separate unit but may be incorporated into the paging terminal controller  31  if the system  30  does not include a storage and retrieval unit  32 , or into the storage and retrieval unit  32 , if the system  30  does not include a paging terminal controller  31 . The systems  30  and base stations  34  may communicate with each other through the PSTN  35  or through links or lines other than or in addition to the PSTN  35 , such as through an SS7 backbone of a wireless network or through the Internet. 
     Additionally, each of the base stations  34 A and  34 B may be part of a paging network but are preferably part of a cellular network. Either one or both of base stations  34 A or  34 B may page the paging transceiver and either one or both of the base stations  34 A or  34 B may deliver the contents of messages to the paging transceiver. Each of the systems  30 A,  30 B, and  30 C may store messages on behalf of a user with the messages being of the same or different types. Furthermore, the messages stored within a single system  30  may be all the same type or may differ from each other. 
     As an example, system  30 A may store voice mail messages and email messages directed to the user&#39;s office, system  30 B may store voice mail messages directed to the user&#39;s home, and system  30 C may store audio messages. The base station  34 A acts as a clearinghouse for all messages delivered to the user to any of the systems  30  and pages the paging transceiver  100  whenever a message is received. Thus, when a voice mail message or email message is received at system  30 A, the system  30 A delivers a page to base station  34 A which is then delivered to paging transceiver  100 . When a voice message is received at system  30 B, the system  30 B sends information about the message to system  30 A and system  30 A then delivers a page to base station  34 A for delivering the page to the paging transceiver  100 . Similarly, when system  30 C has an audio message it notifies system  30 A and system  30 A acts to have the page delivered to the paging transceiver  100 . 
     An example of the data transmission  201  sent from system  30 B or  30 C to system  30 A is shown in  FIG. 11 . The data transmission  201  includes system ID information for identifying the system  30  from a potential plurality of systems  30 . The system ID information may be an address code or may comprise the telephone number of the system  30  and may be automatically captured by system  30 A, such as from Caller ID or from DNIS information. The data message  201  also identifies the paging transceiver(s)  100 , such as with an address code or MIN. For many systems  30 , the message or information stored will often be for a single user whereby the transceiver ID would be the address code or MIN for that single paging transceiver  100 . For other systems  30 , however, the system  30  may want to broadcast a single message to a plurality of paging transceivers  100  whereby the transceiver ID may be a code that identifies a predefined group of paging transceivers  100 . 
     The data transmission  201  also includes message information. The message information includes information identifying the message and preferably also includes information specifying the type of the message, the length of the message, and the message priority. The message identification may identify the message with a unique code, such as a number, or may specify the address in system  30  for the message. The message type advantageously indicates whether the message is a voice message, email message, audio message, video message, or text message. The message length indicates the size of the message and the message priority indicates the priority level of the message. For instance, the user can designate priorities based upon the telephone number of the caller leaving the message or the priority may be set by the caller. Although the data transmission  201  preferably includes this information, the data transmission  201  may include additional or fewer fields than the example provided in  FIG. 11 . 
     The data transmission  201  also includes additional information that may be relayed and presented to the user. For instance, for many systems  30  that receive and store messages on behalf of the user, the additional descriptive information preferably comprises a return address for identifying the caller&#39;s telephone number to inform the user as to who left the message. For other systems  30  which may generate their own information, the additional information preferably describes the information available to the user. For instance, for a system  30  that allows users to sample songs, the additional information would indicate the title and the artist of the song and may also specify the cost to retrieve and play the song. Other uses of the additional information will be apparent to those skilled in the art. 
     The page sent to the paging transceiver  100  includes most, if not all, of the data transmission  201 . The information transmitted to the paging transceiver  100 , with reference to  FIG. 7 , may be inserted into a short message transmitted to the user at step  98 . From the system ID information, the paging transceiver  100  can determine which system  30  it needs to respond to in order to act upon a message. For instance, system  30 A may page the paging transceiver  100  and indicate that system  30 B has a stored message. If the user selects the retrieve message function, then the paging transceiver  100  can contact system  30 B through base station  34 B to retrieve the desired message. The paging transceiver  100  as discussed above may instead respond to base station  34 A to retrieve the message and base station  34 A would communicate with system  30 B to retrieve or otherwise act upon the message. 
     The message information is used by the paging transceiver  100  to inform the user of the message or information stored at the system  30 . The message type, length, priority, and additional descriptive material may be displayed or otherwise indicated to the user at the paging transceiver  100 . From this information, the user can decide what type of action to take upon the message or information at the system  30 . 
     As described with reference to  FIG. 9 , a call to the system  30  may be required in order for the paging transceiver  100  to perform a desired function. If a call is required, the paging transceiver  100  relays information in the data transmission  201  to the system  30 . If the paging transceiver  100  responds to a system  30  other than the one storing the message or information, the paging transceiver  100  identifies the system  30  storing the message or information and also identifies the message. As discussed above, the message may be identified in a number of ways, such as with a message code or by specifying the location in memory where the message is stored. The call to the system  30  would automatically provide the transceiver identification information to the system  30 , although the paging transceiver  100  could provide this information with the other information provided to the system  30 . 
     Upon receiving a call from the paging transceiver  100 , the system  30  reads the transceiver identification and message information to find the information requested by the paging transceiver  100 . The information obtained from the paging transceiver  100  at the system  30  and the transfer of the requested information to the paging transceiver occurs at step  135  in  FIG. 9 . 
     The system  200  can present substantial cost savings to conventional paging systems. With a conventional paging system, the entire message is transmitted to the location of the paging transceiver  100 . For instance, if the user&#39;s home base is in Chapel Hill, N.C., and the message originates in Chicago, Ill., then the message is typically sent over the PSTN  35  to the home base. With nationwide paging, the user may have traveled to San Diego, Calif. whereby the home base would then send the entire message from Chapel Hill to San Diego. With system  200 , on the other hand, only the data transmission  201  is transmitted from Chicago to Chapel Hill and from Chapel Hill to San Diego. The actual message, in contrast, is sent directly from the storage facility in Chicago to San Diego, thereby reducing charges associated with the transfer between Chicago and Chapel Hill. Moreover, the data transmissions  201  between systems  30  may occur over the Internet. These transmissions, for instance, may be formatted according to the Voice Profile for Internet Mail (VPIM) and the addresses of the transceivers  100  may be determined from an open directory service, such as the Lightweight Directory Access Protocol (LDAP) or X.500. 
     The systems  30  and  200  allow a user to easily manage the multitude of messages that are commonly received every day. Conventionally, a user would have to call in to the office voice mail to retrieve voice messages, call home to retrieve voice messages sent to the house, and connect with the computer network at the office to retrieve email messages. Although paging systems have been used to notify a user that a voice mail message or other message has been received, the user would still have to call in to a separate system to actually retrieve the message. The system  200 , on the other hand, enables a user to be notified of all messages, regardless of their type and regardless of their location and furthermore allows the user to selectively retrieve, save, erase or perform other functions on the messages. The systems  30  and  200  and paging transceiver  100 , moreover, allow the user to exercise control over the remotely stored messages; the user can selectively store, save, retrieve, erase, forward, send or otherwise perform operations on messages stored at a remote location. 
     The forgoing description of the preferred embodiments of the invention has been presented only for the purpose of illustration and description and is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Many modifications and variations are possible in light of the above teaching. 
       FIG. 12  shows process flow for when the user of devices such as paging transceiver  100  wishes to play a selected message (i.e. a message from John Doe). The operator simply presses keys or otherwise manipulates or actuates the interface in a manner to cause the interface to recognize a “play” input, step  501 . This can occur via any man/machine interface components which feature appropriate properties, including appropriate look and feel, structure, cost, compatibility with electronic and structural environment and convenience. Such components can, for instance be conventional keypad, single dimension or multi dimension mouse coupled to an appropriate screen, buttons, voice actuated, or other components. Flow proceeds to step  502  where CPU  27  determines if the message identifier information selected corresponds to a message stored at the paging transceiver  100 . If yes, flow proceeds to step  503  where the message is read from message memory  5  and the message is played. If at step  502  the result is no, flow proceeds to step  504  where if the paging transceiver  100  is on line flow proceeds to step  506 . If it is not, the call process is activated to go on line as previously described and flow proceeds to step  506  where the message is read from store and retrieval unit  32  and played for the operator while the message is simultaneously stored in paging transceiver  100  message memory  5 . The process ends at step  507 . 
       FIG. 13  shows process flow for when a message is playing and the user wishes to use the interface to create a ‘pause,’ step  520 . Flow proceeds to step  521  where a test is made to determine if the message is being played. If the message is playing from system  30 , flow proceeds to step  522  where the message that the operator hears is paused while the message continues to be recorded in paging transceiver  100  message memory  5 . Flow proceeds to step  523  where CPU  27  determines if the operator released the pause function. If not, the paging transceiver remains in pause mode (i.e. muted) and the process ends, step  524 . If at step  523  the operator releases the pause button, flow proceeds to step  527  where the message begins to play from the location in memory from which pause was last pressed. The process ends at step  528 . If at step  521 , it is determined that the message is playing from message memory  5 , flow proceeds to step  525  where playing of the message is suspended and flow proceeds to step  526  where a test is made to determine if the operator released the pause button. If no, the process ends, step  529 . If yes, the message begins to play from the last paused address and the process ends at step  528 . 
       FIG. 14  shows process flow for when the user wishes to ‘erase’ messages using the interface. CPU  27  determines if the paging transceiver is on line or off line, step  541 . If off line, flow proceeds to step  543  where the selected message is erased and the process ends, step  544 . If at step  541 , it is determined that the paging transceiver  100  is on line, the selected message at the paging transceiver (if any) and the corresponding message at the system  30  are both erased and the process ends, step  544 . 
       FIG. 15  shows process flow where the user desires to ‘save’ messages. At step  560 , flow proceeds to step  561  where it is determined if the paging transceiver  100  is on line or off line. If off line, a save message flag is set which corresponds to any selected message which may reside in the paging transceiver  100 , step  563 . If on line, flow proceeds to step  562  where the selected message is saved at the paging transceiver  100  (if any) and the system  30 . If at step  562  the selected message does not reside at the paging transceiver  100 , it will be retrieved from the system  30  and saved at both locations. The process ends at step  564 . 
     For the purpose of illustration only, a wireless mobile telephone will be used as an exemplary wireless messaging device. However, it should be understood that other messaging devices, such as pagers, wireless PDA&#39;s and the like, are also contemplated. 
     A wireless mobile telephone, hereinafter mobile phone, is configured to receive text messages and message alerts. The mobile phone may be configured to receive Short Messaging Service (SMS) email messages or the mobile phone may have a Web Browser for accessing an Internet based email service. An email server receives an email message intended for a specific mobile telephone. An email message includes a message body and a message header. The message header usually includes various fields, such as a To field, a From field, and a Subject field. The message header also may include a Message Type field and other information common in email messages. 
     The email server assigns a message identifier (ID) to the message and, in one embodiment, forwards the entire message and the message ID to a mobile system for transmission to the targeted mobile phone. Alternatively, the email server may send to the mobile system just an alert, the From field, and/or the Subject field, but not the entire message. Depending on what was transmitted to the mobile system, the mobile phone user may read the entire message, read whom the message was from, read the message subject or read the message ID. 
     Whether the entire message or just part of the message header was transmitted to the mobile phone, the mobile phone user may choose to reply to the message. To reply to the message, the user may simply press a button to automatically transmit to the mobile system information that identifies the mobile phone user and the message to which the user is replying. The mobile phone user may be identified by the mobile phone&#39;s mobile identification number (MIN) or by data associated with the received message, such as the message ID described above. Similarly, the message to which the user is replying may be identified by the message ID. In one embodiment, the message ID is a reply code (i.e., a short string of letters and/or numbers, such as 1234). Alternatively, the message ID is a telephone number (or pseudo telephone number) that is associated with a message processing system. For example, the email server may assign a callback telephone number to a specific message. Upon receiving the message and callback number, the mobile phone user may simply activate the reply mode causing the callback number to be transmitted for identifying the mobile phone user and or the specific message being replied to. 
       FIG. 16  illustrates the messaging system  600  described above and  FIGS. 17A and 17B  illustrate the steps performed by the components of system  600  when a mobile phone  610  user replies to an email message with a voice message. First, the email server  616  receives the email message from the Internet  620  or from another source (step  202 ). The email server  616  stores the message and assigns a message identifier (ID) to the email message (step  204 ). The message ID may take any number of forms as previously described but for the purpose of example, the email server assigns to the message a telephone callback number (e.g., 202-555-1212) or pseudo telephone number (e.g., #71 or #112). 
     Next, the email server  616  determines whether it should send to the mobile phone  610  the entire email message or just part of the message (for example, one or more fields of the message header) (step  206 ). This determination can be based on a user profile that is stored at the email server  616 , or maybe specified by the user for one or a particular group of email messages. Thus, some users may create a profile that specifies that they want to receive the entire message, whereas other users can specify that they don&#39;t want to receive the entire message and can specify which portions of the message they do want to receive. If the entire message should be sent, then the entire message plus the callback number generated in step  204  is forwarded to the mobile system  614  (step  208 ). If the entire message should not be sent, then the email server  616  forwards, at the least, the callback number generated in step- 204  to the mobile system  614  (step  210 ). The mobile system  614  comprises a message center, a call switching center, and transceiver circuitry necessary for transmitting information to the antenna  612  and the mobile phone  610 . The mobile system  614  then transmits to the mobile phone  610  the information forwarded by the email server  616  (step  212 ). 
     Upon receiving at the mobile phone  610  the information forwarded by the email server  616 , which at the least includes a callback number, the user may choose to send a reply message to the originator of the email message (step  214 ). The user can accomplish this by activating a reply command. Upon activating the reply command, the mobile phone automatically places a call to the callback number. Alternatively, instead of activating the reply command, the user may manually call the callback number by entering the callback number using a keypad on the mobile phone  610 , or by speaking the callback number into the receiver of the mobile phone  610 . 
     In one embodiment, all of the callback numbers generated by the email server are associated with message processor  618 , thus upon placing the call to the callback number, the mobile system  614  routes the call to the message processor  618 , which then answers the call. The message processor  618  may comprise a voice store and forward system for receiving voice and forwarding voice messages. Voice store and forward systems are readily available and are commonly configured to communicate with networked systems such as the email server  616 . The email server  616  communicates with the message processor  618  for establishing a temporary mailbox associated with a specific callback number, which was assigned to a message. 
     When the message processor  618  receives a call directed to a specific callback number, the message processor  618  prompts the mobile phone user to dictate a reply message for the specific recipient identified by header information contained in the original message (step  216 ). The message processor  618  records the voice reply message, notifies the email server  616  of the voice message, and provides the email server with the callback telephone number that the user dialed (or that the mobile phone  610  automatically dialed in response to the user activating the reply command) (step  218 ). 
     The email server  616  uses the callback telephone number to retrieve the email message associated therewith (step  220 ). The email server  616  then transmits to the originator of the email message associated with the callback telephone number at least the voice message recorded by the message processor  618  (step  222 ). In one embodiment, only the voice message is transmitted, in other embodiments, the voice message plus the email message associated with the callback number are transmitted. 
     The message processor  618  may be replaced with another type of processor depending on the media type. For example, instead of utilizing a voice message processor, a video message processor may be utilized in a broadband system for sending video messages from a mobile phone. 
     Messages sent from the email server may be transported over the Internet  620  or a private network. The mobile system  614 , email system  616  and message processor  618  may be directly connected or they may be connected via a network such as the Internet or the public switched telephone network. 
     As described above, a mobile phone user may reply to messages that were not transmitted in their entirety to the mobile phone  610 . In one embodiment, a mobile phone user might receive only a name for identifying the message originator and/or a subject but not the body of the message. Such would be the case in a system that allows the mobile phone user to decide which messages should be transmitted. In the case where the user does not receive the entire message, the mobile phone user could reply to the originator of the message stating, “I will attend to your message when I return to the office.” Optionally, the mobile phone user could read the subject matter and then send a request message to the email server  616 , which causes the email server to transmit the entire message or the remainder of the message. Lastly, a mobile phone  610  equipped with a web browser may connect to an Internet based mail system for reading messages. A reply code, callback number or message code may be embedded in the internet mail based message, thereby enabling a mobile phone user to reply to a specific message as described above. 
     A significant feature of the present invention described above is the ability to “directly access” a specific message from the mobile phone  610  for replying to or for performing an action thereon. Each message transmitted to or accessed from the mobile phone  610  has a message ID associated therewith. A mobile phone user (for example) may reply to a message, delete a message from the email server  616  without retrieving the entire message, forward a message and retrieve a message. The user may also mistakenly delete a message stored in the mobile phone  610  and then retrieve it again from the email server  616 . Unlike prior art email and voice mail systems, the present invention provides for direct access of remotely stored messages for retrieval and for performing an action associated therewith, as is described in the above mentioned related U.S. patent application Ser. Nos. 08/934,143, 08/933,344, 08/934,132, and 08/934,337. 
     The invention of  FIG. 16  is shown configured with one email server  616  and one message processor  618 . However, multiple email servers  616  and or message processors  618  may be configured in the system, for example, via network connection, direct connect, or the Internet. This approach, when used in conjunction with the email industry standard POP3 mail, allows the mobile phone user to access email from a plurality of email systems. 
     Any email server  616  may send message alerts, header information, message codes, subject matter, or the body of a message to the mobile system  614  for transmission to the mobile phone  610 . Alternatively, the email server  616  and or the message processor  618  (shown in  FIG. 16 ) may act as a master system for commutating with the mobile system  614  and slave email servers  616  and or slave message processors  618  may be configured to communicate with the master email server  616  and or a master voice processor  618  for communicating with the mobile phone  610 . 
     As previously stated, a mobile phone user may receive any part of the message or the entire message. While some mobile phone users may decide to have the system alert them and automatically deliver the entire message, other mobile phone users (power users) may wish to be alerted and automatically receive only the sender&#39;s name and the subject of the email message. The mobile phone user may then decide to retrieve the message, delete the message, forward the message or reply to the message. The present invention provides the mobile phone user direct access to and remote control of email messages regardless of where the email messages reside. 
     The mobile phone  610  can originate email messages by utilizing an address book or by direct entry of an address or an abbreviated address. The address book may be stored in the mobile phone  610 , on the email server  16  or in the message processor  618 . The mobile phone user may simply select a name from the mobile phone&#39;s  610  address book, activate a send message command and send a message to the message processor  618  for delivery to the email server  616  and finally to the addressed destination as previously described. 
     In another embodiment, the mobile phone user may enter the address manually or enter an abbreviated address associated with the actual address stored on the email server  616  and or the message processor  618 . In another embodiment, the mobile phone user may utilize a mobile phone  610  that has Internet access capability such as the so-called “smart phones”. Upon accessing the Internet, the mobile phone user may access an Internet based email system such as Hot Mail, Yahoo Mail and the like. The Mobile phone user may then choose a message to read, reply to a message or select a name from an address book for originating a message. The user then selects a send command for sending a message (digital, analog, or other) to the Internet based email system or the email server  616 . The selected address book entry may contain addressing information for identifying a particular email server or message processor. Upon the mobile phone user&#39;s selection of a message recipient, the mobile phone  610  connects to the identified email server  616 , message processor  618 , or another system for delivering the email message. An email message may also be routed to a particular system based on the type of email message For example, a voice message may be directed to a voice message processor and a text message may be directed to an email server. The mobile phone  610  may connect to the Internet for sending a-message or a phone call may be placed to the message processor  618 . Alternatively, a mobile phone user may indicate to an email server that he/she wishes to send a message, such as a voice message, to a particular destination. The email server then informs the message processor  618  that the specific mobile phone user wishes to send a message. The message processor then places a call (or connects) to the mobile phone  610  and prompts the mobile phone user to record a message as previously described. 
     The present invention provides for receiving an email message that has an attachment (i.e., an attached file). The mobile phone  610  does not need any special modifications to receive a text message and for example a voice attachment (i.e., the attached file contains a voice message). When a mobile phone  610  receives a text message having an attachment associated therewith, the mobile phone user may receive all or a portion of the text message, header information, an alert, and a message code which identifies the attachment. To hear the voice message attachment, delete the voice message, reply to the originator of the voice message, or forward the voice message to other people, the mobile phone user simply places a call to the message processor  618 , enters the message code that identifies the attachment using a keypad (or if the message processor  618  has voice recognition capability, simply speaks the message code), and enters a code corresponding to an action or speaks a command, such as reply, delete, forward, save, etc. The message processor  618  performs the command. 
     That is, the message processor  618 , upon receiving a call from a mobile phone user, may be configured to identify the mobile phone user utilizing the industry standard caller ID. After identifying the mobile phone user, the message processor prompts the mobile phone user to enter the message code associated with the received message for retrieving the corresponding voice attachment. The voice message file corresponding to the message code is then accessed by the message processor  618 . The message processor  618  then plays the message to the mobile phone user over the telephone connection so that the mobile phone user can hear the attachment. 
     In this manner, unlike prior art voice mail systems, the present invention provides direct access to a specific message. The mobile phone user need not scroll through a large number of messages in order to locate a specific message. 
     Upon accessing a message file, the message processor  618  allows the user to erase the message, forward the message, or record a reply for the voice message originator. In another embodiment, the mobile telephone may be configured to automatically transmit a message code to a specific message processor as previously described. The main difference between a message code for retrieving a voice attachment and a reply code is that a message code for retrieving a message directs the message processor to play the message while a reply code directs the message processor  618  to record a reply message. 
     Voice attachments may be retrieved manually by entering a message code or automatically. The mobile phone user may place a call directly to a specific message processor  618  or the call may be automatically directed to a specific message processor that corresponds to a received system identification code or the call may be directed to a specific telephone number associated to the mailbox within the message processor  618  where a specific message resides. 
     The mobile phone user may additionally access a voice message by accessing a web based email system with a browser-enabled mobile phone  610 . The web based email server may supply the message code and upon a mobile phone user activating a retrieve command, the mobile phone  618  places a call to a message processor  618 . Alternatively, the web based email server may notify the message processor  618  and the message processor  618  then connects with (or calls) the mobile phone  610  and plays the message to the mobile phone user. The message processor  618  is adapted to play an analog voice file or a digital voice file. The voice message may be streamed to the mobile phone  610  for real time reproduction or the voice file may be transferred to the mobile phone  610  for storage in a memory device within the mobile phone  610 . The message is not limited to an analog or digital voice message buy may include streaming video or other multimedia content. 
     It has been clearly shown that an email text message and an attachment may be received or retrieved by the mobile phone  610 . Email messages may be sent to the mobile phone  610  from a number of devices such as for example, a computer with Internet access to a web based email system or from a computer utilizing an email program. The present invention additionally provides for sending email messages from a mobile phone  610  to another mobile phone  610  (i.e. mobile-to-mobile) or to itself (i.e. memo mode). A mobile originated voice message may be recorded and addressed by a mobile phone user to a targeted mobile phone  610 . The difference between sending a message to a computer or to a mobile phone  610  is simply the address. The present invention makes it possible to communicate two-way email, including attachments between a computer and a mobile phone and between mobile phones. Mobile phone users need not scroll through messages to access a specific message. Messages may be directly accessed for performing an action thereto. A mobile phone user may simply select a destination address, activate a send message command and record a voice email for any targeted destination. A mobile phone user may activate a reply command and record a voice email that is automatically or manually addressed to a message originator. Messages may be automatically received, manually retrieved, replied to, forwarded, deleted, originated and reproduced by the mobile phone  610 . The need for a mobile phone to have browser capability for accessing the Internet to communicate two-way email is eliminated. 
     As previously stated, the present invention may be configured to deliver entire text email messages to a mobile phone  610  or just a portion of the message, such as the name of the originator and/or the subject. Additionally, a message may be received from the email server  616  on demand by the mobile phone  610 . A mobile phone user may automatically receive a name and subject information but may not wish to automatically receive the entire message. After the mobile user reviews the received names and associated subjects, the mobile phone user may decide to retrieve the remainder of the message or the entire message. 
     A message may be deleted from the mobile phone  610  but it may be again retrieved from the email server  610 , if the message is still stored on the email server  610  as previously described. The ability to retrieve a specific message on demand allows for new and improved features for the mobile phone  610 , a paging device or other types of wireless email and messaging devices. 
     One such feature of the present invention is an improved memory management arrangement and method for automatically deleting messages stored in a mobile phone or messaging device when the device&#39;s memory is full. For example, prior art paging devices have a limited amount of memory for storing messages. There are times when the memory is full of messages and new messages cannot be received and stored. Other paging devices automatically delete the oldest read message in order to make room in memory for a newly received message. These prior art devices and methods have a disadvantage because once a message is deleted or over written, it cannot be recovered. The present invention provides a system for deleting messages when memory is full but the deleted or over written messages may be again received and stored by the mobile telephone  610  as will be described hereinafter. 
     The mobile phone  610  may be configured so that an internal processor executes the following process: Receive and store messages in memory. When a message is received and memory is full, over write one or more message bodies, but retain the message header and the message ID associated with the message, to make room for the new message. Store the new message. When over writing message bodies, over write the oldest read message body first, when there are no read message bodies left, over write the oldest unread message body. When there are no more message bodies, over write the oldest read subject first. When there are no more read subjects, over write the oldest unread subject. The mobile phone  610  may be configured to delete the name and header information using the same priority as described above. 
     The above-described process causes the mobile phone  610  to over write only message bodies when there is not enough memory to store an additional message. The mobile phone user may continue to save and view information that identifies the message originator (the name) and information describing the message (the subject). If the mobile phone user desires to read an entire message body that was deleted or over written, a retrieve command may be activated by the mobile phone user for causing the mobile phone  610  to transmit the selected message ID to the email server  616 . Upon receiving the retrieval request and message ID, the email server  616  sends the email message corresponding to the message ID to the requesting mobile phone  610 . An over written or deleted message can now be recovered. 
     The present invention provides for sending and receiving messages based on one or more variables. The email server  616  and the message processor  618  may be configured with Instant Messenger software such as is provided by Microsoft, America On Line, AT&amp;T and others. These programs provide notification when a computer-messaging device is on line or the operator is logged in. When the message processor  618  or email server  616  receives a message for the mobile phone  610 , the message may be held until the mobile phone is on line. In other words, when the user is logged in or when the presence of the user is detected, the message is delivered. Conversely, when a message is sent to a mobile phone  610 , the message may be held by the email server  616  or the message processor  618  until the presence of the mobile phone  610  or the mobile phone user is detected. Detection of the mobile phone  610  may for example be accomplished by interfacing a home location register (HLR) to the email server  616  and the message processor  618 . HLR equipment is readily available and used extensively by mobile phone companies to provide detection of a mobile phone in a particular service area in order to route calls. Detection of a mobile phone user may also be accomplished by detecting user-activated commands that are transmitted to the email server  616  or the message processor  618 . Detection of an operator, mobile phone user or active messaging device enables the present invention to perform actions responsive to the status of messaging devices or the presence of their respective user. The email server  616  may automatically route messages to a mobile phone  610  when the mobile phone user is utilizing the mobile phone  610 . Then, when the mobile phone user turns the mobile phone  610  off and logs in to an office computer, the email server routes messages to the office computer. The present invention may perform any number of actions or combination of actions based on a mobile phone user activated command or by automatically detecting the status of the mobile phone  610  and or the presence of the mobile phone user. Messages may even be redirected automatically to a mobile phone user&#39;s computer email service if the message cannot be delivered to the mobile phone  610  because the mobile phone  610  was out of range or turned off. 
     The email server  616  and the message processor  618  may automatically perform an action or sequence of actions based on the time of day, the date, the status of a mobile phone  610 , the presence of a user, user activity, geographic location of the mobile phone  610  or any number of conditions which may be transmitted to the email server  616  or the message processor  618 . Sensors may be added to the mobile phone  610  and data from the sensors may be automatically transmitted or manually sent by the mobile phone user. A temperature sensor, for example, may be included in the mobile phone  610  wherein temperature readings are automatically transmitted to the email server  616 . Based on temperature, the location of the mobile phone  610  and the presence of the mobile phone user, the email server  616  or the message processor may for example send an email message to the mobile phone user that includes an advertisement stating, “The temperature is 98 degrees. Please drink Coke. 35 cent special one block away at the super store.” Alternatively, the mobile phone user may configure the present invention so that messages from particular people are delivered to the mobile phone  610  on week days between 9:00 am and 5:00 pm but otherwise routed to the mobile phone user&#39;s home computer and have copies of all message activity go to an office email system. Messages may also be filtered based on the location of the mobile phone  610  so that very important messages are routed to the mobile phone  10  when the mobile phone user is out of town with the mobile phone  610 . A mobile phone user may also configure the system to send a notification message to the mobile phone  610  when another mobile phone  610  user or a computer device user is detected by the email server  616  or the message processor  618 . 
     The present invention may be utilized in telephone systems, paging systems, email systems, and numerous communications systems. 
     Similar process flow may be implemented for other functionality which is desired in access and management of messages according to the present invention. 
     The foregoing disclosure is provided for purposes of explanation and illustration of various embodiments and features of the invention. Modifications and changes may be made to the disclosed subject matter without departing from the scope or spirit of the invention. 
     The embodiments were chosen and described in order to explain the principles of the invention and their practical application so as to enable others skilled in the art to utilize the invention and various embodiments and with various modifications as are suited to the particular use.