A PORTABLE COMMUNICATION APPARATUS HAVING FIRST AND SECOND USER INTERFACES, AND AN ACCESSORY DEVICE COMPRISING A KEYPAD AND A DISPLAY FOR A PORTABLE RADIO TELEPHONE

Abstract: A portable communication apparatus (1), such as a mobile telephone, has a main apparatus housing, a first user interface with a first keypad, such as an ordinary telephone keypad, and a first display. The apparatus also has a second user interface with a second keypad (22), preferably a typewriter-type keyboard, and a second display (32), which preferably is larger than the first display. The second keypad (22) and the second display (32) are detachably connectable to the main apparatus housing of the portable communication apparatus (1).

Description: A PORTABLE COMMUNICATION APPARATUS HAVING FIRST AND SECOND USER INTERFACES, AND AN ACCESSORY DEVICE COMPRISING A KEYPAD AND A DISPLAY FOR A PORTABLE RADIO TELEPHONE Technical Field The present invention relates to portable communication apparatuses of the type having a main apparatus housing and a user interface comprising a keypad and a display. Prior Art Portable communication apparatuses of the kind described are of course commonplace. A well-known example is a cellular or mobile telephone, which operates for instance in a GSM system (Global System for Mobile communications in Europe) or D-AMPS (Digital Advanced Mobile Phone System, in the United States of America) . In addition to their basic role as a means for per- forming wireless communication of speech between human users, contemporary mobile telephones often provide a plurality of services other than just communication of speech. One very common service is the ability to send short text messages (for instance SMS - Short Messages Services in GSM) , where a user of a telephone may generate a text message, containing a predetermined maximum number of alphanumeric characters, and then send it across the mobile telephone network to an intended receiver. In a standard mobile telephone, the ordinary tele- phone keypad thereof will be used for entering the textstring (string of alphanumeric characters) to be incorporated in the message. Since an ordinary telephone keypad typically only contains keys for the digits 0 through 9, and a few other keys such as a * key and a # key, this limited set of different keys will have to represent a larger number of different alphanumeric characters, for instance the 25 different characters of the English alphabet. In reality, each numeric key 0-9 must represent several different alphanumeric characters. For instance, the numeric key 2 may represent the alphanumeric characters A, B, C, as well as country-specific characters, such as A, A, AE, a, ς, I, and also the digit 2. The user will choose between different characters by depressing the numeric key 2 for a different number of times in sequence. The same approach is used for creating and editing entries in an electronic telephone book, which is normally included in the mobile telephone. While many people use their mobile telephones mainly for speech calls, other user categories frequently use the above options for generating text messages and/or creating/editing entries in the electronic telephone book. In particular, people that have a mobile occupation or lifestyle are in many cases frequent users of such text-based services. Well-known examples of such people are young peo- pie (teenagers) and business people. For frequent users of the text-based services of a mobile telephone, the ordinary telephone keypad is a far from perfect tool for inputting text into the mobile telephone. Having to press different keys repeatedly for dif- ferent number of times is tedious, time-consuming and inefficient. Therefore, there is a pronounced need for an improved way of inputting text into a mobile telephone. Moreover, the standard display of a mobile telephone normally has a restricted size and is therefore only capable of presenting a limited number of different characters at the same time . A previously known solution to the problem of providing an improved user interface is a device, which is a combination between a mobile telephone and a portable computer. Such a device (often referred to as a personal digital assistant - PDA) is disclosed in EP-A-0 776 140 and comprises two separate user interfaces and an outer housing, which can be unfolded. When the outer housing is closed, the device has the appearance and size of an ordinary mobile telephone, wherein a first user interface is available, which substantially corresponds to an ordinary telephone user interface (i.e. a display and a numeric telephone keypad) . When, on the other hand, the outer housing is unfolded, a second user interface is exposed, which offers a larger display and an alphanumeric keyboard. The alphanumeric keyboard and the large display of the second user interface may be used for inputting alphanumeric messages (textstrings) , for instance for generating an SMS message or for manipulating an entry in an electronic telephone book. The large display of the second user interface may also be used in a graphic mode for displaying images etc. While the device of EP-A-0 776 140 offers several useful features, it has a few distinct drawbacks for cer- tain types of users. Firstly, the device is considerably more advanced than an ordinary mobile telephone. Consequently, the price thereof as well as the necessary knowledge level of the user is considerably higher than for an ordinary mobile telephone. Furthermore, the overall apparatus size, weight and power consumption are larger than for an ordinary mobile telephone . Therefore, for users that either do not have enough money to buy an advanced PDA device known from EP-A-0 776 140, or simply do not find the various advanced features thereof to be of any particular usefulness from their personal point of view, the device of EP-A-0 776 140 does not represent an optimal solution to the problem of facilitating the input of text to a mobile telephone. Summary of the Invention In view of the above, it is an object of the present invention to provide an accessory device, which will make it easier for a user of a mobile telephone to input text into the telephone, without having to rely solely on the ordinary numeric telephone keypad thereof . Another object of the present invention is to provide a portable communication apparatus, which is more flexible than the prior art devices. More specifically, the portable communication apparatus shall appear in a compact size, having a low weight and a low power consumption, in situations where the user is only interested in normal telephony services (communication of speech) . On the other hand, in situations where more advanced features than normal speech communication are required (such as text processing or presentation of graphic information) , the portable communication apparatus shall provide a user interface, which is better for these services. The above objects have been achieved by a portable communication apparatus, which has a main apparatus housing, a first user interface with a first keypad and a first display, and a second user interface with a second keypad and a second display, where the second keypad and the second display are detachably connectable to the main apparatus housing of the portable communication apparatus. The objects are also achieved by the provision of an accessory device for a portable radio telephone of the above type, where the accessory device has a device housing comprising first and second housing portions, a second keypad is provided in the first housing portion, a second display is provided in the second housing portion, engagement means are provided for physically and operatively connecting the accessory device to the radio telephone, and controller means are adapted to receive keystrokes entered by the user on the second keypad and are also adapted to present the entered keystrokes on the second display. Other objects, features and advantages of the present invention will appear from the following detailed disclo- sure of a preferred embodiment, from the drawings as well as from the attached subclaims. Brief Description of the Drawings The present invention will now be described in more detail, reference being made to the accompanying drawings, in which: FIGs 1-3 are schematic views of a portable communication apparatus and a detachable accessory device according to a preferred embodiment of the present invention, and FIG 4 is a schematic block diagram of a printed circuit board and the fundamental components thereon according to the preferred embodiment of the accessory device. Detailed Disclosure of a Preferred Embodiment FIG 1 illustrates a portable communication apparatus 1 together with an accessory device 2 according to a preferred embodiment of the invention. For the rest of this specification, the portable communication apparatus 1 will be exemplified by, and referred to as, a radio telephone, and more specifically a mobile GSM telephone. The mobile telephone 1 is per se essentially known from the prior art and comprises an apparatus housing 10, an antenna 11 mounted on top of the housing, a loudspeaker 12 provided in an upper front portion of the housing, a visual display 13 and a microphone 14 , which also are provided at the front portion of the apparatus housing 10. Moreover, the mobile telephone 1 comprises an ordinary numeric telephone keypad having a plurality of numeric keys 16, each of which represents a respective digit 0 through 9. A * key and a # key 17a, 17b are also provided and have ordinary functions. The keypad also comprises a YES key 18a, which in a conventional way is used e.g. for answering an incoming call, or for performing an affirmative action in any routine or option provided by the man-machine interface of the mobile telephone 1. A NO key 18b similarly has a function for providing a negative response to any such function within the man-machine interface. It will also be used in an ordinary way for terminating an ongoing call. Moreover, it may be used as a power-on key for turning on the mobile telephone 1. The telephone keypad also comprises a clear key 18c, which for instance may be used for resetting the man- machine interface to an initial state (escaping from any option within a menu system provided by the man-machine interface) , and arrow keys 18d, 18e, which are used for scrolling through different options in the man-machine interface. The mobile telephone 1 also comprises, at a lower end of the apparatus housing 10, an accessory connector 15, which may be used for connecting the mobile telephone 1 to any commercially available accessory device, such as a hands -free set or a battery charger. The lower portion of FIG 1 discloses a novel accessory device 2 having an external connector (not shown) to be detachably inserted in the accessory connector 15 of the mobile telephone 1 by pushing the accessory device 2 towards the mobile telephone 1 in a direction indicated by an arrow in FIG 1. The accessory device 2, which is illustrated in more detail in FIGs 2 and 3, comprises a first housing portion 20 and a second housing portion 30. The housing portions 20 and 30 are coupled to each other by means of a hinge mechanism 44. The accessory device 2 is securely mounted to HJ ft fD tr fD fD 0 ) Hj CQ fD 0J ØJ tr Hi -> fD CD H- Hi Oc 0 ) fD ω rt 0 CD Hi ts H- rt tr CQ fD 3 3 fD 0 3 tr tr H- fD H{ CD Φ» ft to fD ~ H-" fD CO TJ C tr Ω 0 tr ts fD ØJ CQ H ØJ tr ^ CO Ω 3 Hf fD fD 0 ) s; ts CQ o CD Hh CD 0J tr 0 £ tl machine interface of the mobile telephone 1. Preferably, the function keys comprise a key for generating a text message (such as an SMS message in GSM) to be sent to another user. When this SMS function key is pressed, the logic circuitry inside the accessory device 2 (shown in more detail in FIG 7) will form a digital control signal, preferably in the form of an AT command sequence, which contains a sequence of commands that will cause the mobile telephone 1 to enter an option for generating and sending an SMS message in the man-machine interface of the telephone 1. In other words, striking the SMS function key will cause the mobile telephone 1 to enter its menu option for sending an SMS message, and the user will be provided with an empty display 32 having a blinking cursor, which indicates that the mobile telephone 1 is ready to receive an entered text message character by character. The user may now enter the text message, character by character, by striking the different keys of the keyboard 22. All entered characters will be shown on the display 32, and the user may navigate within the entered text message by means of the navigation keys 35-38 provided to the right of the display 32 on the second housing portion 30. Once the message has been completely entered, it may be submitted by pressing the YES/OK button 33. Similarly the function keys of the keyboard 22 may comprise a phonebook key, which will invoke another option in the man-machine interface of the mobile telephone 1, viz. an option for entering the electronic telephone book thereof . As already mentioned, the accessory device 2 comprises an external connector (not shown in the drawings) at the upper portion thereof. The purpose of this connector is to mate with the accessory connector 15 of the mobile telephone 1, so as to operatively connect the accessory device 3 to the mobile telephone 1. The connector of the o o 3 rt Oi tr fD rt IV ιv Ω μ- 0J Ω Hi tr TJ 0 rt Hi rt 3 fD Ω CO 3 fD μ- 3 0J 0J 0 ø ) fD h- Hi fD CD fD O CQ μ- ts 0 μ- 0 H μ- Hh fD CD tr 0 0 c 0 tr ts Hj fD Ω ^ rt CD 0 *< rt • : 3 CD Qi ts H! 0J μ- ts h- 1 Ω ro tr fD ts TJ Hi fD fD fD 3 Ω rt 01 fD Ω tr CD CO 3 H- TJ ft CQ Hi tl (D 0J fD CD μ- Ω rt TJ fD Ω rt tr CD tr tr X rt h- 1 0 Ω rt fD TJ Hi ft o. rt CQ Ω TJ μ- TJ rt øJ h- i rt μ- tr 0J (D CQ fD CD rt fD Hi fD øJ rt Hi Hi TJ 0J fD 0 fD rt tr <J Hj CD Hi Ω ^ CQ h t! CD Oi Hj CQ 0 Ω 0 2 Hi Hi μ- 0 Ω *< Hi H- 1 t *> Oi ? fD μ- 0 CD fD μ- rt TJ μ- Oi CQ 0 μ- C ts 0 Oi ti ιv μ- fD Hh h- 0 σ fD rt t) tl CO Hi rt Ω CO TJ fD Ω μ- TJ Hj fD tr rt μ- Hi |J CQ fD øj 3 J 0 CD c o Ω Hi Ω CQ fD fD fD H- Ω 0J < Ω ft 0 ^ TJ rt CD CD Ω fD H CO fD CO Hi Hi CO μ- CD • Hi H- 1 TJ 0 ts μ- μ- Ω fD H! 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H- 1 tr fD 0 øJ fD 0J CQ |J> μ- Hi μ- (0 - Hi 3 rt CO fD μ- μ- 3 Ω 0 CQ CD Ω fD O CQ Hi Hj H ts Ω CQ fD tr • : TJ <i 0 fD ^ 0 Ω rt 0 h- i Hj Hi TJ fD TJ Ω μ- O CQ C s: |J 0 0 0) H- fD CQ ts 3 TJ μ- C rt 0 ts μ- CO 0 ts h- 1 H- IV t) ~ μ- μ- ti tr H 3 0 ti Ω ts ts Ω tr 0 ti Hi 0 ts ts rt ts CQ c 0J CD 0- TJ rt ts μ- σ μ- μ- Hh CO Ω rt • tr fD s- rt rt Ω Hi fD CD CD tr tr o. 0 ) H • ; H- 0J Hi Hi μ- Ω Ω 3 μ- CD fD CD μ- Hi fD fD tr CD - t) Ω CQ fD μ- CQ CQ <J CQ 0 tr 0 ts tr μ- Hi CD rt tr CQ Hi 3 ts CQ Hi Hi fD CQ rt <J tι CD ^ rt μ- CQ 0 Hi Oi o 0 ts tr μ- CO ts tr 0J CD tl . — . ft øJ μ- 0 fD 3 CQ 3 μ- Hi Oc z H! 3 μ- tr TJ rt CD H-" 0 øJ fD rt CO 3 Hi 0J tr tr CQ tJ Hi 0 CD rt 0J 0 C CD ø Hi < Ω Hi - μ- H{ ^ μ- - 0J Hi Ω 0J CD fD CQ TJ tr fD t ^ <! 3 i ft μ- CO o 0 x rt ^ TJ Ω ^ 0 Ω rt Hi TJ hi μ- tl rt CD H μ- O i ts Ω rt CD ^ Ω Hi H{ 3 TJ fD rt CD 3 3 0 fD h-> CQ 0 H- μ- *» 0 0 rt ts fD tr < Oc 0J μ- μ- CD tr 0 CQ CD tr μ- D ≤ - fD 0J 3 Hi H- 1 IV 0J ti o ts øJ tr fD CO fD tr Hi CD < ts H- 1 Hi rt CO HJ rt 3 fD CD CQ fD 0 ) ι-3 CD CD CQ o fD Ω CQ 0 0 <! μ- rt H^ CD <! tr fD O "i tr tr Hi rt rt fD 3 Ω tr tr ^ ft rt rt 0 Ω 0J Hi μ- rt (D d Hi CD fD Hi Hi Hi π> CD fD 3 tr 0 h- 1 CD CQ Hj Hi Ω 0 X TJ fD H| 0 Hi Ω •• < o. CO CD ^ CD Ω Hi CQ Hi -~ fD fD ts CD fD C- 0 CD c Oi t) Oi Ω (D rt t) rt 3 CO 0 Ω 0 CO c 3 CD ts Hi ts 3 μ- Hi Ω 3 rt • <; Hi 0 rt 0 μ- Ω Hi Ω tr 0 O hh CD Hi TJ μ- TJ rt CQ CD fD CD ts fD rt TJ tr TJ rt Hi Hi to t) to ts μ- øJ CD fD tr c fD μ- Hi TJ ts tr - Ω -> 3 HJ μ- Hi fD o 0 0 0 M rt • Hi rt μ- Hi <! rt <! fD Hi h- i fD 0 Hi rt fD 0 Hi fD 0 μ- ts CO 0J Hi rt Ω μ- TJ H- 1 Ω μ- tr μ- CQ CD ^ ti fD £ μ- Ω H{ CD ts ts to Ω fD øJ ts 0J O > tr 0 0 C fD CD Ω fD t TJ CD Ω tr d rt • ! O Ω CQ fD 0 rt ^ fD t ) h- 1 fD H- ts Hi fD CQ 0 TJ H- 1 fD μ- CQ Hj TJ CD CO ts tr 0 Hi o. h- J rt ft TJ tr ts 0 μ- H CQ Ω 0 (P> 0 ft 1 CD Hi H- 0 0 ) 0 c CO α s; ts . CQ tr ts l ts 0 0J |J ts Hi CQ CO rt μ- CD fD fD H- σ CO ts H CQ fD fD 0 ts Hi CQ CQ Ω fD O 0J Hh Q • memory, such as an EEPROM memory. Moreover, it may advantageously be integrated with the controller 410, particularly if the latter is realized as a programmable microprocessor. The printed circuit board 410 also comprises a display driver circuit 450 for presenting text characters or graphical information on the display 32. According to the preferred embodiment, the accessory device 2 communicates with the mobile telephone 1 over a serial communication interface at a rate of 9600 bps . Therefore, the printed circuit board 400 is provided with a transceiver for performing serial communication with the mobile telephone 1. In the preferred embodiment the transceiver 440 is realized as a Universal Asynchronous Transmitter Receiver, which is connected to the additional accessory connector 25 of the accessory device 2. Naturally, the transceiver 440 is also connected to the upper connector of the accessory device, i.e. the connector which is adapted to mate with the accessory connector 15 of the mobile telephone 1. In the preferred embodiment, all keystrokes detected by the accessory device 2 will be sent through the accessory connector 15 to the mobile telephone 1, and more particularly to the central controller thereof, which controls and operates the man-machine interface of the mobile telephone 1. This information is preferably sent as AT command sequences. Simarly, the controller 410 of the accessory device 2 is adapted to receive text or graphic information to be presented on the large display 32. In this way, the accessory device 2 may be used not only for entering text but also for browsing the Internet in WAP applications (Wireless Application Protocol) . In this respect, the navigation keys 35-38 may be used for moving a cursor across the display 32, and the YES/OK key 33 may be used for performing operations similar to mouse clicks. t o o ØJ TJ TJ fD ts o. fD Oi μ- t Oc fD TJ (D ts o. fD t rt T øJ rt fD tl rt Ω 0J μ- 3 CO

Claims: CLAIMS 1. A portable communication apparatus (1) having a main apparatus housing (10) , a first user interface with a first keypad (16-18) and a first display (13) , and a second user interface with a second keypad (22) and a second display (32) , characterized in that the second keypad (22) and the second display (32) are detachably connectable to the main apparatus housing (10) of the portable communication apparatus (1) . 2. An apparatus as in claim 1, wherein the second keypad (22) and the second display (32) are formed as an accessory unit (2) . 3. An apparatus as in claim 2, wherein the accessory unit (2) is divided into a first housing portion (20) , in which the second keypad (22) is provided, and a second housing portion (30), in which the second display (32) is provided. 4. An apparatus as in claim 3, wherein the first housing portion (20) and the second housing portion (30) are pivotally coupled to each other. 5. An apparatus as in claim 4, comprising a hinge (44) between the first housing portion (20) and the second housing portion (30) . 6. An apparatus as in any preceding claim, wherein the first keypad (16-18) and the first display (13) are provided at a front portion of the main apparatus housing (10), while the second keypad (22) and the second display (32) are provided at a rear portion of the main apparatus housing. 7. An apparatus as in any of claims 2-6, wherein the main apparatus housing (10) comprises a first connector (15) for allowing an accessory device to be coupled to the portable communication apparatus (1) , and wherein the accessory unit (2) comprises a second connector adapted to mate with the first connector (15) . 8. An apparatus as in claim 7, wherein the accessory unit (2) comprises a third connector (25) , which is essentially identical to the first connector (15) . 9. An apparatus as in claim 7 or 8 , further comprising a battery, wherein the accessory unit (2) is adapted to receive electric power from the battery through the first and second connectors. 10. An apparatus as in any preceding claim, wherein the first keypad (16-18) is an ordinary numeric telephone keypad and wherein the second keypad (22) comprises alphanumeric keys essentially corresponding to those found on a typewriter keyboard. 11. An apparatus as in any of claims 3-10, wherein the second housing portion (30) comprises a third keypad (33-38) , which has keys (35-38) for navigating a cursor on the second display (32) . 12. An apparatus as in claims 11, wherein the third keypad (33-38) has keys (33-34) for performing affirmative and negative actions in the second user interface. 13. An apparatus as in claims 11, wherein the third keypad (33-38) has keys (33-34) for performing affirmative and negative actions in the second user interface as well as the first user interface. 1 . An apparatus as in any preceding claim, wherein the apparatus is a radio telephone, preferably a mobile or cellular telephone. 15. An apparatus as in any preceding claim, wherein the accessory unit (2) comprises a controller (410), serial communication means (440), keystroke detecting means (420) for detecting keystrokes on the second keypad (22) , and a display driver (450) for the second display (32) . 16. An accessory device (2) for a portable radio telephone (1) of the type having a first user interface comprising a first keypad (16-18) and a first display (13) , the first user interface having an option for allowing a user to enter text on the first keypad to be presented on the first display, the accessory device being characterized by a device housing comprising first and second housing portions (20, 30) , a second keypad (22) provided in the first housing portion (20) , a second display (32) provided in the second housing portion (30) , engagement means (42) for physically and operatively connecting the accessory device (2) to the radio telephone (1) , and controller means (410-450) adapted to receive keystrokes entered by the user on the second keypad, and adapted to present the entered keystrokes as a text on the second display (32) . 17. An accessory device as in claim 16, wherein the first housing portion (20) and the second housing portion (30) are pivotally coupled to each other. 18. An accessory device as in claim 17, comprising a hinge (44) between the first housing portion (20) and the second housing portion (30) . 19. An accessory device as in claim 17 or 18, wherein the engagement means (42) comprises a connector adapted to mate with a corresponding accessory connector (15) of the portable radio telephone (1) . 20. An accessory device as in claim 19, further comprising an additional connector (25) , which is essentially identical to the accessory connector (15) of the portable radio telephone (1) . 21. An accessory device as in claim 19 or 20, adapted to receive electric power from a battery of the portable radio telephone (1) through the accessory connector (15) thereof . 22. An accessory device as in any of claims 16-21, wherein the second keypad (22) comprises alphanumeric keys essentially corresponding to those found on a typewriter keyboard . 23. An accessory device as in any of claims 16-22, wherein the second housing portion (30) comprises a third keypad (33-38) , which has keys (35-38) for navigating a cursor on the second display (32) . 24. An accessory device as in claim 23, wherein the third keypad (33-38) has keys (33-34) for performing affirmative and negative actions in the first user interface . 25. An accessory device as in any of claims 16-24, further comprising a controller (410) , serial communication means (440), keystroke detecting means (420) for detecting keystrokes on the second keypad (22), and a display driver (450) for the second display (32) .

Inventors: BARVESTEN MATS, BARVESTEN, MATS
Applicants: ERICSSON TELEFON AB L M, TELEFONAKTIEBOLAGET L M ERICSSON (PUBL)
Application year: 2000
Main classification: H04M1
IPC codes: H04M1