Portable receiver unit of a paging system

Abstract: Portable receiver unit of a paging system, comprising a housing in which an electronic circuit is accommodated. The electronic circuit comprises display means with a display screen fitted in a side wall of the housing and another display screen disposed in a front wall with a greater surface area than the side wall of the housing. The display screens are intended for displaying data stored in a memory of the circuit, which together with an identification code allocated to the unit, may have been received by the circuit as part of a transmitted message sent by a transmitter of the system. The data of the transmitted message can be different types of data and each group of a particular type can comprise a type data item. The circuit detects the type data item for displaying on one or both of the screens the data received and belonging to the detected type data item. The message can also comprise a control data item for rotating the display of data on a screen through a multiple of 90°. The operating modes of the unit determined by the type data items and the control data item received can also be achieved by control switches of the unit.

Description: The invention relates to a portable receiver unit of a paging system, comprising a housing in which an electronic circuit is accommodated, the electronic circuit having display means with a display screen fitted in a wall of the housing, for displaying data stored in a memory of the circuit, which data, together with an identification code allocated to the unit, may have been received by the circuit as part of a transmitted message sent by a transmitter of the system. A portable receiver unit of the type mentioned above is known in practice. The known receiver unit has a single display screen. The display screen is fitted in a side wall of the housing with a relatively small surface area. The disadvantage of this is that relatively few data can be displayed on the screen. An alternative is for the screen to be placed in a front wall of the housing with a relatively large surface area. Although more data can be displayed in this way, the screen often cannot be read directly by the user when paged, in particular if the unit is clipped to an edge of a garment, including a belt. The object of the invention is to eliminate the disadvantages of the two different embodiments of the known receiver unit and to extend its display facilities. This object is achieved according to the invention for the receiver unit of the type mentioned in the preamble through the fact that the display means comprise two display screens, of which one screen is disposed in a side wall of the housing, while the other screen is disposed in a front wall with a greater surface area than the side of the housing. GB-A-2 216 703 discloses the use of a single front display which may be viewed from a side via a mirror. US-A-4 534 063 discloses a single display which may be seen by rotating the housing. An advantage of the unit as invented is that the data can be displayed on both screens simultaneously, in which case it can be arranged for the most important data to be displayed on the screen which is easiest for the user to read directly. As an alternative, the screen on which the data received by means of the last transmitted message are displayed can be determined by a data item included in the transmitted message. In particular, the latter data item is the type of data item which indicates the type of data of a group of data of the transmitted message. In this way the two screens can be addressed separately or simultaneously from the transmitter, in order to display data. The use of the two screens also makes it possible to control one or both of the screens independently of each other, in such a way that the display of data on them can be rotated through a multiple of 90°. This is useful in particular if a clip is provided on the rear wall of the housing, opposite the front wall, for clipping the unit to a garment, and if the side wall with the screen is a top side wall. Irrespective of whether the front wall or the rear wall of the housing lies opposite his body when it is being worn by the user, the unit can be controlled in such a way that it is always easy for the user to read the last-mentioned screen directly, in particular if the display on the screen is rotated through 180°. This also applies to the other screen in the front wall, in particular if the front wall is not covered by a garment. The invention is explained with reference to the drawings. In the drawings: Fig. 1 shows in perspective an embodiment of a portable receiver unit according to the invention; Fig. 2 shows the portable receiver unit of Fig. 1, dismantled; Fig. 3 shows an embodiment of an electronic circuit of a portable receiver unit according to the invention; Fig. 4 shows a circuit diagram for the operation of an electronic circuit of a portable receiver unit according to the invention; and Fig. 5 shows a circuit diagram of a further operation of a portable receiver unit according to the invention. Fig. 1 shows an embodiment of a portable receiver unit 1 of a paging system according to the invention. The receiver unit 1 comprises a housing 2 with a top side wall 3 and a front wall 4. The receiver unit 1 comprises an electronic circuit which is shown in Figures 2 and 3. The electronic circuit comprises display means having a first display screen 5 disposed in the top side wall 3 and a second display screen 6 disposed in the front wall. Light indicators 7 and 8 are also fitted in the top side wall 3. The light indicator 7 is used for indicating the reception of a transmitted message from a transmitter of the paging system. The indicator 8 is for indicating whether the voltage of a battery of the electronic circuit is correct, and for indicating correct positioning of the receiver unit in a rack. The receiver unit 1 also comprises a number of switches, for example two, in particular push button switches 9, which can be operated by a user of the receiver unit for selecting an operating mode of the unit 1 with display of data belonging to the selected mode. Fig. 2 shows the receiver unit 1 of Fig. 1 dismantled. As can be seen in Fig. 2, the housing 2 of the unit 1 comprises two elongated shells 10, 11. The shell 10 comprises the top side wall 3, the front wall 4 and parts of the other side walls. The shell 11 comprises the rear wall 12 and parts of the last-mentioned other side walls. A clip 13 can be fitted against the rear wall 11. The clip 13 comprises a bracket 14 of which ends can be inserted through openings 15 in the rear wall 11 and can be locked there in a suitable manner, for example through a snap connection or an adhesive connection. The clip 13 also comprises a lever 15 which is fixed to the bracket 14 by means of a hinge with a pin running parallel to the base of the bracket 14. The clip 13 comprises a spring (not shown), by means of which a bottom clip part 16 of the lever 15 is forced against the rear wall 11. Pressing against the other end 17 of the lever 15 produces a space between the clip part 16 and the rear wall 11, with the result that the unit 1 can be pushed over an edge of a garment. An electronic circuit, comprising a printed circuit board 18, is fitted inside the housing 2. A number of components of the circuit are disposed on the board 18, such as an aerial 19 and a substrate 20 on which a microprocessor 21 and components for controlling the display screens 5 and 6, the light indicators 7, 8 and background lighting elements (not shown) for lighting the screens 5 and 6 are fitted. The light indicators 7, 8 each comprise a light-emitting diode (LED) 7a, 8a, respectively, which is covered by a light-transmitting cap 7b, 8b, respectively. The display screens 5, 6 are connected by means of flexible flat conductor strips 22, 23, 24 to the board 18 and the substrate 20. The board 18 has a recess 25 in which a battery (not shown) can be placed. The battery can be placed in the housing 2 through a passage 26 in the rear wall 11, following which the passage 26 can be covered by a slide 27. Fig. 3 shows a diagram of an embodiment of an electronic circuit of the portable receiver unit according to the invention. The diagram shows top display means 30 and front display means. The top display means 30 comprise the top display screen 5 and a screen driver 32 which supplies all control signals required by the screen 5. The screen driver 32 itself receives suitable control voltage signals from a voltage generator 33. In a similar way the front display means 31 comprise the display screen 6, a screen driver 34 which supplies all the required control signals to the screen 6, and a voltage generator 35 which supplies suitable control voltages to the screen driver 34. The screen drivers 32 and 34 receive data from a memory 37 through a communication bus 36. The screen drivers 32 and 34 may comprise buffer memories (not shown) for storing information therein which has to be displayed on the screen 5, 6, respectively. This means that the data to be displayed need only be transferred once from the memory 37 through the bus 36 to the screen drivers 32, 34. The bus 36 is connected to the microprocessor 21, which is also connected to a keyboard 9. Also connected to the bus 36 are a decoder 38, a driver 39 for the LED 7a, a driver 40 for the LED 8a, a driver 41 for a background LED 42 for the screen 5, a driver 43 for a background LED 44 for the screen 6, and an electromechanical driver 45. A light-sensitive diode 46, which is disposed in a suitable manner for receiving ambient light from the receiver unit 1, is also connected to the drivers 41 and 43. As the light-sensitive diode 46 receives more light, the drivers 41, 43 control the background LEDs 42, 44 so that they emit less light. An acoustic signalling element 47, for example a loudspeaker, and a vibrator 48 are connected to the electromechanical driver 45. The electronic circuit also comprises a receiving section or receiver 49, of which an input is connected to the aerial 19, and of which an output is connected to the decoder 38. The receiver 49 is suitable for receiving a signal which is transmitted by a transmitter of the paging system, and which is modulated with a message containing an identification code allocated to the receiver unit and data for display thereof on the screens 5 and/or 6 and/or for controlling the acoustic signal transmitter or the vibrator 48. The receiver 49 then supplies a bit stream to the decoder 38 which detects the format used in the paging system of a message in the bit stream, and which corrects the bit stream if necessary. The decoder 38 supplies the detected and if necessary corrected data through the bus 36 to the microprocessor 21. The microprocessor checks whether the data received contain an identification code allocated to the receiver unit. During this process, the microprocessor 21 compares the identification code received with one or more identification codes allocated to the receiver unit 1 which can be stored in a preferably rewritable readable section of the memory 37. If identity is established there, the microprocessor 21 processes the other data received. The microprocessor 21 stores data received which are to be displayed on one or both of the screens 5, 6 in a random access section of the memory 37. Thereafter the microprocessor 21 can supply the latter data periodically from the memory 37 to the screen drivers 32, 34 for display thereof on the screen 5, 6, respectively. As an alternative, the screen drivers 32, 34 can, as stated earlier, have buffers for storage therein of the data to be displayed, with the result that such data need be transferred only once from the memory 37 through the bus 36 to the screen drivers 32, 34. As another alternative, the microprocessor 21 can store the data received for display directly in buffers of the screen drivers 32, 34. The use of two display screens 5, 6 according to the invention instead of a single display screen means that the data received can be displayed in different ways. This will be explained below with reference to Figures 4 and 5, which show flow diagrams of a number of operating modes of a receiver unit 1 according to the invention. In the flow diagrams "Y", "N" represent the answers "YES" and "NO", respectively, to the question asked in an adjacent block. The operation of the receiver unit is determined, as known per se, by a program which is stored in a memory, which in particular is a read-only part of the memory 37. The flow diagram shown in Fig. 4 represents a program section which the microprocessor 21 can always call on when data is received from the decoder 38. The flow diagram shown in Fig. 5 represents a program section which, with time division, can be constantly active and can be processed by the microprocessor 21. Each of these program sections comprises an initialisation step, which is indicated in Fig. 4 by block 50 and in Fig. 5 by block 51. Fig. 4 also shows an end block 52, the only significance of which is that the microprocessor 21 continues with a program section designated outside the diagram of Fig. 4. According to the invention, a message transmitted by a transmitter of the system and received by a portable receiver unit 1 may comprise one or more groups of data, and each group may contain a data item, called the type data item, which indicates the type of data in the group. According to the invention, the display of a group of data received depends on its type data item. If, according to block 53 of Fig. 4, the data type received is a first data type, the system continues with block 54, and otherwise with block 55. According to block 54, the data received for display are displayed on a first screen of the two screens 5 and 6. If according to block 55 the type data item received is a second type data item, the system continues with block 56, and otherwise with block 57. According to block 56, the data received for display are displayed on the second screen of the two screens 5 and 6. If according to block 57 the type data item received is a third type data item, the system continues with block 58, and otherwise with block 59. According to block 58, the data received for display are displayed, depending on their number, on the first or on the second screen. According to block 59, the data received are displayed both on the first and on the second screen. The blocks 54, 56, 58 and 59 are followed by the end block 52. A diagram such as that shown in Fig. 4 is particularly applicable if the screen drivers 32 and 34 have buffers in which the data to be displayed can be stored. If the data to be displayed always have to be read cyclically from the memory 37 and transferred to the screen drivers 32 and 34, the end block 52 in Fig. 4 could be omitted, the program section is processed with time division, and after the blocks 54, 56, 58 and 59 the input side of the block 53 is returned to, or the blocks 54, 56, 58 and 59 are themselves subroutines which can be interrupted by the microprocessor when new data are received. Within the scope of the invention more data types are possible for displaying data received in a different way from that with reference to Fig. 4. A fourth type data item can, for example, indicate that the data received must be displayed on the first screen, and that the data displayed earlier on the first screen are shifted. A fifth type data item can indicate that the last data received are to be displayed on the first screen and the data displayed earlier on the first screen replace the data displayed earlier on the second screen. Sixth and seventh type data may be identical to the fourth and fifth type data, and in the explanation in the two paragraphs above "first" and "second" are interchanged. An eighth type data item may indicate that with a display such as that indicated in block 58 the data displayed earlier are shifted. A ninth type data item can indicate that only the acoustic signal transmitter 47 or the vibrator 48 must be controlled. In this connection it is pointed out that a message transmitted by the transmitter of the paging system may simultaneously contain data to be displayed on a screen 5 and/or 6 and a data item for controlling the signal transmitters 47, 48. In addition or as an alternative, the ways of displaying data on the screens 5 and 6 explained above can be selected by a user of the receiver unit 1 by operating the keyboard 9. According to the invention, a user of the receiver unit 1 can select the orientation of the data displayed on the screens 5 and 6 separately for each screen 5, 6. This can be useful if a clip is disposed on the rear wall of the housing, opposite the front wall, for clipping the unit to a garment, and if the side wall with the screen is a top side wall. Irrespective of whether the front wall or the rear wall of the housing is opposite the user's body while he is carrying it, the unit can then be controlled in such a way that the user can always easily read the last-mentioned screen, in particular if the display on the screen is turned through 180°. This also applies to the other screen in the front wall, in particular if the front wall is not covered by a garment. Fig. 5 shows a flow chart for achieving this. If according to block 60 of Fig. 5 a "screen key" is pressed, the system continues with block 61, and otherwise with block 62. According to block 61 the microprocessor 21 refers a command received thereafter to another screen 5 or 6, or to both screens 5 and 6. If, for example, the screen key is pressed once, the first screen is selected, after pressing twice the second screen, after pressing three times both screens, after a fourth time again the first screen, and so forth. After block 61 comes block 62. If according to block 62 a "rotation key" is pressed, the system continues with block 63, and otherwise the input of block 60 is returned to. According to block 63, each time that the rotation key is pressed the display of data on the selected screen, or on the two selected screens, is always rotated through 90°. As an alternative, the step can always be 180° instead of 90°. If the keyboard 9 has multifunctional keys, the "screen key" and "rotation key" need not be separate keys, but their functions can be fulfilled by pressing keys of the keyboard 9 simultaneously or in a certain sequence. The operation with reference to Fig. 5 for rotating the display of data on one screen or on both screens can also take place within the scope of the invention by making the transmitter send suitable control signals for it with the message. These control signals may be represented by data of the message. The rotation of the display of data on a screen is considered to lie within the scope of a person skilled in the art. If, for example, a screen consists of a matrix of light-emitting or light-transmitting/non-light-transmitting elements to be controlled separately, and said matrix is divided into columns and rows, the columns and/or rows need only receive information folded over with respect to their middle column or row etc., or they are scanned in reverse order, and the data are transferred if necessary in reverse order from the memory 37 to the screen drivers 32, 34.

Claims: Portable receiver unit of a paging system, comprising a housing in which an electronic circuit is accommodated, the electronic circuit having display means with a display screen fitted in a wall of the housing for displaying data stored in a memory of the circuit, which data, together with an identification code allocated to the unit, may have been received by the circuit as part of a transmitted message sent by a transmitter of the system, characterised in that the display means comprise two display screens, of which one screen is disposed in a side wall of the housing, while the other screen is disposed in a front wall with a greater surface area than the side of the housing. Portable receiver unit according to claim 1, characterised in that the circuit detects different types of data to be displayed, and depending on a detected type the circuit controls the display means for displaying the data of the detected type on one or both of the screens allocated to the type. Portable receiver unit according to claim 2, characterised in that the type of a group of data of the transmitted message is determined by a type data item of the group. Portable receiver unit according to claim 1, characterised in that on receipt of a transmitted message the circuit controls the display means in such a way that the data of the message are displayed on one of the screens and data displayed earlier on that screen are displayed on the other screen. Portable receiver unit according to claim 4, characterised in that one screen is a screen disposed in a side wall of the housing. Portable receiver unit according to one of the preceding claims, characterised in that in one of its operating modes the circuit controls the display means for rotating the display of data on a screen through a multiple of 90°. Portable receiver unit according to claim 6, characterised in that the screen on which the display of the data is rotated is a screen disposed in a side wall of the housing, and the angle of rotation is 180°. Portable receiver unit according to claim 6 or 7, characterised in that the operating mode for rotating the display is determined by a switch of the circuit which can be operated from outside the housing. Portable receiver unit according to claim 6 or 7, characterised in that the operating mode for rotating the display is determined by a control data item of the transmitted message.

Inventors: VAN ARDENNE ARNOLD, VAN ARDENNE, ARNOLD
Applicants: ERICSSON RADIO SYSTEMS BV, ERICSSON RADIO SYSTEMS B.V.
Application year: 1992
Main classification: G08B5
IPC codes: G08B3, G08B5