GB2362237A - Modular personal digital assistant - Google Patents

Abstract

A Personal Digital Assistant (PDA) has a base unit (1M) with at least a battery holder and a display (2D) and a number of changeable modules (1C) which slot, slide or clip into the base unit. The modules have various functions including: processor, memory, modem, phone, tv/teletext, radio, GPS, voice recognition. Some modules may be wireless and have RF or infra-red links. Modules may incorporate programmable logic interfaces and be upgraded by reprogramming. The base unit may also include any combination of: processor, memory, peripheral interfaces or a system clock. The PDA may be used for internet access. It may also be configured as a navigation aid giving road traffic information, or as an electronic wallet for e-commerce transactions.

Description

2362237 MODULAR PERSONAL DESIGN ASSISTANT This,invention relates to a

modular personal design assistant.

Personal Design Assistants or PDAs are hand held computing devices for personal computing. They are compact by their very nature and consist of a display screen, optional keypad and interfaces to connect to other peripheral devices. Some have replaced the keypad input with a pen to allow the user to write on a touch screen to input text data. Due to their size, power consumption needs to be reduced to maintain battery life.

However, Personal Design Assistants are fixed units with limited applications. Like PCs and mobile phones, when a new standard is introduced or a new application is devised the old PDA effectively becomes redundant. There are no means of reconfiguring the basic PDA to the new application. In fact, the applications for a PDA are quite limited e.g. as a word processor, text editor, notepad, time manager and limited games.

With the increase in silicon gate counts, low power technologies and the use of mixed signal technologies comes better system performance and the chance to implement new techniques and / or algorithms which exploit these improvements in smaller areas. However, for manufacturers to gain market advantage and exploit greater processing power, data needs to be transferred at every faster rates. This requires new interfaces (such as Universal Serial Bus (USB), Firewire, xDSL and wireless access such as Bluetooth. Consequently, interfaces and processors are constantly being developed every 12 - 18 months requiring the customers to update their systems to stay "in touch". Though many of these systems are backward compatible, this leads to reduced performance, with systems requiring more software and processing power to execute the required functions. Also, not all manufactures sign up to the same interface consortiums and differences exist in similar equipment. An example would be the recent introduction of digital terrestrial television and digital satellite television in which both set top boxes use MPEG2 video transport but the former is received via a conventional television aerial and the latter by a satellite dish.

Having a modular PDA, which could be easily upgraded to new standards and or be reconfigured by the user for use in different applications, would be a great advantage over today's PDAs.

According to the present invention there is a modular and or reconfiguarble personnel design assistant apparatus consisting of either a base unit which houses a minimum of the display means, internal battery holder means and one or more slots to hold card modules or a base unit which houses a minimum of the display means, intemal battery holder means which employs a set of self contained slide / clip together modules with interconnection means to allow these modules to slide / clip together securely and communicate information between the modules, the combined modules forming a larger more complex self contained unit, the functionality of the modular PDA being determined by the choice of card modules or self contained slide / clip together modules, these card modules or self contained modules implementing fixed functions and or have programmable and or reconfigurable logic means allowing the function of the card module or self contained module to be changed in either real or non-real time, the user being able to construct a personal design assistant apparatus from the various card modules or self contained clip together modules targeted at the desired application, the personal design assistant also being upgradeable and reconfigurable to existing and new applications by downloading new or upgrade software or firmware, the card modules and or slide / clip together modules providing circuitry means for implementing either or a combination of, but not limited to, the following functions:- a). memory of various types, such as FLASH to store programs and or non- volatile memory, such as SDRAM to store data, allowing the modular PDA's memory capability to be increased, b). a microprocessor, local memory and programmable logic to allow parallel operations to be performed or different hardware functions to be implemented, so the modular PDA has more processing power to enable parallel operations to be implemented, c). one or more modems, such as an Asymmetrical Digital Subscriber Line (ADSQ, g.lite or V.90 modems to allow the modular PDA to connect to the Plain Old Telephone (POTs) system for access to the Internet for example, d). a programmable communication processor which works together with the modem card module and performs segmentation and reassembly of various ATM Adaptation layers (AAL1, AAL2, AAL3/4, AAL5) for ATM traffic flow or Internet Protocols (TCP/IP) for Internet connections, the module optionally performing traffic management functions, such as traffic scheduling, traffic queuing, e). a mobile phone based on the GSM protocol or a third generation protocol, such as the Universal Mobile Telephone System (UMTS), the mobile phone card module consisting of a Radio Frequency (RF) circuitry, link control and management and baseband functions for implementing a GSM / third generation link, f). a card module which implements the RF circuitry, link control and management and baseband functions for implementing a Bluetooth link and or a HomeRF link and or a Wireless ATM (WATM) and or a IEEE 802.11 Wireless Local Area Network (WLAN) link, to allow the modular PDA to communicate with wireless peripherals and or other wireless units, g). a card module which implements Analogue to Digital Converters (ADCs) and or Digital to Analogue Converters (DACs) and or digital interfaces for data acquisition applications, h). a card module which implements a television receiver and or Teletex decoder circuitry so the user can access and view this information on the modular PDA's screen, i). a Digital Audio Broadcast (DAB) decoder and or Frequency Modulation (FM), Medium Wave (MW), Long Wave (LW) radio receiver, # a video and audio processing card module, for example based on MPEG2 and or MPEG 4 to allow a video input to be coded and transmitted and received via the mobile phone card or allow MP3 audio to be decoded, processed and played by the user, k). circuitry that allow the modular PDA to be configured as a virtual test instrument, for example measuring voltages, current, resistance, 1). Global Positioning System (GPS) decoder, m). signal generation circuitry for generating various test waveforms at a wide range of frequencies for use in on-site testing of equipment to allow the modular PDA to be configured as a virtual test instrument, n). circuitry which implements voice recognition functions which allows the user to communicate with the modular PDA applications without the use of a keyboard means.

A specific embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which:- Figure 1 shows different mechanical views of the modular PDA and how card module can be interfaced to the base unit to reconfigure the base PDA into a more complex PDA to suite the desired application; Figure 2 illustrates how the modular PDA can be configured for use as a mobile phone and also implement local wireless links to a user headset, printer and wireless local area network (WLAN); Figure 3 illustrates the concept of a modular PDA based on self-contained clip / slide together modules, which clip / slide together to form a more complex unit to implement the desired applications; Figure 4 shows a logical block diagram of a modular PDA base unit and card module connection; Figure 5 shows an example of how the card modules or self contained modules can communicate with each other using digital switch and serial buses; Figure 6 illustrates an example of how the modular PDA can be configured for use as a test instrument in which one of the card modules is a signal generator another in a voltage, current and resistance measuring card module and the collected information is displayed on the PDA's screen; Figure 7 shows an example of how the modular PDA can be configured for use as a medical monitoring device for monitoring a patient's heart rate, blood pressure, etc.

Referring to figure 1, the modular PDA base unit 1M consists of a display means 2D, such as a Liquid Crystal Display (LCD) for displaying various information, a compartment 1 B for holding batteries to power the apparatus and several general purpose interfaces, such as USB 21 and UARTs 2U. The unit 1M can also include some form of computing device 2H, associated memory 2P / 2L and peripherals. The computing device 2H being a low power microprocessor or RISC device. Extra computing power 2H and memory resources 2P / 2L required for more complex applications can be provided by inserting processor and or memory card modules1C into the base PDA unit 1 M. The card modules 1 C can be released from the modular PDA base unit 1 M by release and eject means 1 R. The release means 1 R are similar to those used currently for PC cards Type 1, 11 and Type 111.

The modular PDA can be configured for various applications by inserting one or more card modules 1 C into the card slots 1 S of the base PDA unit 1 M. The card modules 1 C all having a similar interface to allow the card modules 1 C to be interchanged freely with the base unit 1 M. The card modules 1 C could be based on the PC cards Type 1, Type 11 or Type III cards that are currently used for modems in laptop PCs. However, with greater silicon integration and the concept of system on a chip the card modules I C can implement whole systems and the interface type is not necessarily confined to a PC Type interface mentioned above. A way around the interface problem is for the card modules 1 C or self-contained slide / clip together modules 2M to implement the interface using programmable logic so this can be reconfigured at a later date to accommodate new standards or standard upgrades.

The card modules 1 C will consist of, but are not limited to, the following family of functions and provide circuitry means to implement:1). Memory of various types, such as FLASH to store programs and or nonvolatile memory, such as SDRAM to store data, allowing the modular PDA's memory capability to be increased, 2). A microprocessor, local memory and programmable logic to allow parallel operations to be performed or different hardware functions to be implemented, so the modular PDA has more processing power to enable parallel operations to be implemented, 3). Card modules which implement one or more modems, such as an Asymmetrical Digital Subscriber Line (ADSQ, g.lite or V.90 modems to allow the modular PDA to connect to the Plain Old Telephone (POTs) system for access to the Internet for example, 4). A programmable communication processor which works together with the modem card module and performs segmentation and reassembly of various ATM Adapt ion layers (AAL1, AAL2, AAL3/4, AAL5) for ATM traffic flow or Internet Protocols (TCP/IP) for Internet connections, the module optionally performing traffic management functions, such as traffic scheduling, traffic queuing, 5). A mobile phone based on the GSM protocol or a third generation protocol, such as the Universal Mobile Telephone System (UMTS), the mobile phone card module consisting of a Radio Frequency (RF) circuitry, link control and management and baseband functions for implementing a GSM / third generation link, 6). The RF, link control and management and baseband functions for implementing a third generation (3G) link, such as the Universal Mobile telephone System or UMTS, 7). A card module which implements the RF circuitry, link control and management and baseband functions for implementing a Bluetooth link and or a HomeRF link and or a Wireless ATM (WATM) and or a IEEE 802.11 Wireless Local Area Network (WLAN) link, to allow the modular PDA to communicate with wireless peripherals and or other wireless units, 8). A card module which implements Analogue to Digital Converters (ADCs) and or Digital to Analogue Converters (DACs) and or digital interfaces for data acquisition applications, 9). A card module which implements a television receiver and or Teletex decoder circuitry so the user can access and view this information on the modular PDXs screen, 10). A Digital Audio Broadcast (DAB) decoder and or FM, MW, LW radio receiver, 11). A video and audio processing card module, for exampl e based on MPEG2 and or MPEG 4 to allow a video input to be coded and transmitted and received via the mobile phone card or allow MP3 audio to be decoded, processed and played by the user, 11). Card modules that allow the modular PDA to be configured as a virtual test instrument, for example measuring voltages, current, resistance, 12). Global Positioning System (GPS) decoder, though this function &411 probably be available as part of the third generation mobile card module, 13). Signal generator for generating various test waveforms at a wide range of frequencies for use in on-site testing of equipment.

14). A card module which implements voice recognition functions which allows the user to communicate with the modular PDA applications without the use of a keyboard means.

It will be appreciated by those familiar with the art that the functionality of the card modules 1C and or self contained clip together modules 2M are not limited to those described in items 1 to 14 above and that other functions can be implemented for other applications. Also, the card modules 1 C and or self contained slide 1 clip together modules 2M can implement a combination of the functions mentioned above depending on the functional partitioning of a system.

Having a modular and reconfigurable PDA and a range of card modules 1 C which implement different system functions means the basic base PDA unit 1 M 1 213M can be configured for use in many different applications. This makes the modular PDA very powerful and attractive tool as the apparatus can be easily upgraded and reconfigured by many different users to suite new applications. This advantage means the life cycle of the unit is much longer and a user is more confident that they will receive better Return On Investment (R01) and that their apparatus will not be obsolete within months of purchase.

The modular PDA base unit 1M 1 213M preferably further includes host processor 2H means which allows the individual cards 1C 1 2M to be initialised and configured either autonomously at apparatus power up or during apparatus use. The autonomous initialisation and configuration being based on the so-called 'Plug 'n' Play' mechanism. The initialisation and housekeeping software being stored in the program memory 2P. Local memory 21---is provided.

The operating system used by the modular PDA can also be changed. It could be Windows CE for example or be based on Linux. The operating system being stored in non-volatile memory associated with the control processor.

To allow the maximum flexibility, several processors and associated memory and Input - Output peripheral devices can be provided on a single card module 1 C 1 2M or several card modules 1 C 1 2M. As different applications require different sub-functions, the host controller 2H can allocate the various software sub functions to various processors 1 card modules as necessary. For example, depending on the capabilities of the processor and the required functionality, a processor could run several software sub functions if the processing time permitted and they are effectively sequential operations or the host controller could allocate different software sub functions to different processors (not shown).

This concept can be extended to include implementing system sub functions in programmable logic on the card module 1 C or clip together modules 2M. The use of programmable logic, such as Field Programmable Gate Arrays (FPGAs), is sometime required to implement more complex and time consuming algorithms, which are better suited to hardware implementation. However, the use of programmable logic still requires the host controller 2H to download firmware to program the programmable device to implement the desired sub function or sub functions required in the overall system configuration. This, therefore, is considered part of the Software Definable System (SDS).

Having an array of inter connectable processor elements and programmable logic elements provides the greatest flexibility and programmability when it comes to implementing the desired sub functions which are then combined to form the functionality for the required modular PDA system. The host processor 2H can of course allocate the various sub functions to the different processors or programmable logic devices. This is useful in more complex systems. In this case, the modular PDA can be configured to implement two or more separate functions. Therefore, the host processor 2H would need to allocate the desired sub functions to the relevant processors / card modules 1 C / 2M and programmable logic. This means that the various sub functions don't necessarily have to be performed on the same processors or programmable logic devices. There is not a one to one correspondence between the software sub function and a particular processor or programmable logic device. The allocation of the software sub functions to the various processors and or programmable logic in the system depends on the various system configurations and the system requirements at the time.

The fact that Software Definable Systems (SDS) provided the greatest flexibility (functional re-use and system re-configuration) in system design means that it is expandable and easily upgradeable. The modular PDA can have card module slots 1 S to allow the addition of more processors when a system needs to be expanded. The use of Plug'n'Play facilities means on each card module 1 C or self-contained clip together modules 2M means that the host processor 2H can automatically determine the number and capabilities of the processor and or programmable logic devices available and hence allocate the desired resources accordingly.

Such a system can download new software and or firmware functions or upgrade existing functions from the Internet via the modem card module means. The new upgrade software and or firmware being stored by the host processor 2H in the host memory 2P.

Figure 2 shows how a modular PDA unit is configured as a mobile phone using for example a third generation mobile (such as the Universal Mobile Telephone System UMTS) or GSM card module 1 C. This allows the user to roam freely and communicate with base stations 113S which form a mobile phone network. In this example, the modular PDA is also Bluetooth enabled to allow the creation of local wireless links to other peripherals, such as a user audio headset I H, a visual display and audio headset 1 VH, a printer 1 P or a wireless LAN access point IWL. If voice recognition facilities are provided in the modular PDA, this means that the user doesn't need to attach a keypad means to enter text. The user can speak into the headset 1 H, which will then format, and code the voice data for transmission to the modular PDA via the Bluetooth card module 1 C. The demodulated and decoded data can then be processed by the voice recognition software and or hardware. This is then converted to text and displayed on screen by the application software and hardware and also stored in memory 2L. A pen device 1 PI is used to enter data via the display screen 2D either by pointing to selected icons in a similar fashion to that employed with a mouse or by using writing motions on the screen 2D. In the latter case scribed text is recognised and converted to text allowing the user to write data rather than typing via a keyboard.

Figure 3 shows an example of how the modular PDA can be constructed from self contained slide / clip-together modules 2M or blocks. These blocks have connector means to allow the modules to transfer information between the blocks. For example, the blocks can transfer information either serially and or using parallel buses. Extra batteries 213M can be used which connect to the base unit 213M using clip / slide means.

Figure 4 shows a logical block diagram of a preferred embodiment of a modular PDA base unit or slide / clip together base unit. The base unit 1M contains a host processor 2H, program memory 2P and local memory 2L. The host communicate with peripherals via a bridge circuit means 2B. This could be foe example a PCI bridge. The peripherals include, but are not limited to, a display means 2D, which is controlled by a display driver, and buffer 2E, which configures the information for presentation on the display, means 2D. Information entered via the display means 2D, via a pen for example, is first processed and formatted by the display driver / buffer 2E. The base unit my also have several interfaces for communicating with external peripherals. Therefore, a Universal Serial Bus interface 21 and or UARTS 2U are accessible by the host processor 2H via the bridge 2B. The base unit 1 M also has several card slots 1S for accommodating card modules I C. One of the card slots 1 S is connected to a mobile antenna 2A allowing a mobile phone card module 1 C to interface directly to mobile antenna 2A. Though the card modules 1 C are shown connected to the system bus, card module intercommunication can be via switching means as shown in figure 5. Though a PCI bus system is shown in figure 4, those familiar with the art will realise that other bus system and configuration can be used to interconnect the card modules, the host processor and its peripherals. The modular PDA can be implemented using other system buses that are available, the PCI bus being show as an example.

In one preferred embodiment, data and control transfer from data sources to data processing and data sinks between the various card modules or slide / clip together modules is by data packets. These card intercommunications are all digital using serial or differential serial communications links so as to reduce the number of inter card module routing signals and reduce signal noise between cards. Therefore, any analogue signals are first converted to corresponding digital signals using appropriate digital to analogue signal conversion means. The selection of such conversion means ensuring the correct sampling and quantization requirements to represent the digital form of the signal with minimal quantization and noise errors. To reduce inter card module routing, in-band signalling and control messages can be employed. Data fields in the cell header identify these.

In another embodiment, data and control communication between the base unit and the card modules is by switching means 2SW. Figure 5 shows a logical block diagram of how different card modules or slide / clip together modules can communicate with each other via switching means 2SW. The communication buses can be either serial busses and or parallel buses. Figure 5 shows separate serial input bus 2CI and serial output bus 2CO used for full-duplex communications between the switch 2SW a card module 1C. The switching means 2SW can take the form of a pure cross bar switch in which signal paths between the switch inputs and switch outputs are dynamically set by the host processor depending on the configuration of the apparatus. The switching means 2SW can also be a self routing buffered switch fabric in which data packets are transferred from the switch's input ports to the switch's output ports based on routing information contained in the header section of the data packet. As several inputs could route data packets to the same switch output port, buffering is required. To reduce congestion different priority queues could be used in the switch 2SW to allow higher priority traffic preference over lower priority traffic. This allows real time traffic and traffic requiring a better class of service to pass through the switch fabric with a lower latency and hence reduce timing errors. The switch paths and header fields are set by the host processor at system start-up or if there is a new configuration update.

By allowing data packets to be identified by channel address means, data traffic from several sources can be routed to the same card module using the same signal path. This reduced the inter card module complexity.

The advantages of using a switch 2SW to route data packets between different card modules and devices within these card modules are that it reduces the complexity of the inter card routing and consequently the base unit. Each card slot does not require connections to all other possible card slot locations. Control and data messages can be switched to the correct card module via the switching means 2SW. This makes it easier to configure the system and allows the card modules to be placed almost anywhere in the modular PDA apparatus as the host processor card can interrogate each card to determine it's function and initialise it and the system accordingly. Also, certain card modules can incorporate Plug'n'Play means, which allows card modules to initialise and or assist in configuring themselves. Another preferable feature is for the card modules to be 'hot swappable'. This feature allows card modules to be removed or inserted into the apparatus card frame while the system is operational.

The data and control packets are routed to the various destination card modules via a switch 2SW having switching means to transfer control and data from many input card modules to many receiving card modules simultaneously. The switching action being either pre configured or selfrouting. The data packets preferably being of the same length as used in the Asynchronous Transfer Mode (ATM) protocol or can be varying length packets. Buffering, segmentation and reassembly and packet routing means being provided.

A user could configure the modular PDA for use in their car. The apparatus could be used as a substitute for a navigation system and or traffic congestion notification system, such as that employed in a "Traffic Master". The apparatus would interface to a cradle in the car where is would connect to an external power supply and antenna means. The modular PDA would be configured with the appropriate radio decoder card module to receive the traffic congestion information and a GPS card module to allow real time navigation. Other navigation application examples include use of the modular PDA in both boats and aircraft.

In another embodiment the modular PDA can be configured for use as a test instrument. For example, card modules or slide / clip together modules could be used for data acquisition or measuring voltages, currents and resistances. These latter card modules would have interface and connection means to allow the connection of test probes. Figure 6 shows an application where the modular PDA is configured as a signal generator, oscilloscope and multimeter. Probes 1 CP are used to connect the various test instrument card modules or slide / clip together modules to a Printed Circuit Board (PCB) 3PCB to allow monitoring of signals and other circuit parameters.

In a similar embodiment, the modular PDA can be configured as a portable instrument for use by medical personnel 1 MD in the field i.e. paramedics and ambulance crews. For example, a data acquisition card module 1C will have interface and connection means to allow medical probes 1 MP, such as those used to monitor heart rate, blood pressure, temperature of the patient 1 PT to be connected to the card module 1 C. Data received by the card module 1 C is processed and displayed on the screen of the modular PDA. If the modular PDA also has a mobile phone card module inserted into one of the available slots on the apparatus then the patient data can also be transmitted in real time to medical staff at a remote destination allowing experts at the remote location to diagnose the patient's condition and transmit advice back to the medical staff at the scene. Figure 7 shows how a modular PDA can be configured for these applications.

In yet another embodiment, the modular PDA can be configured as an electronic wallet and also be used for remote banking. A card module 1Cwould provide the necessary encryption and authentication circuitry to allow secure access to the users bank account facilities. In the electronic wallet mode, the card module 1C and hence the modular PDA 1M / 2M can be credited with tokens which have a monetary value. The user can then use the modular PDA when purchasing goods. Enabled equipment at the point of purchase would interrogate the modular PDA account circuitry, authenticate the user, verify the value held by the modular PDA, and then decrement the value of goods purchased.

Iz.

Claims (19)

1. A modular and or reconfiguarble personnel design assistant apparatus consisting of either a base unit which houses a minimum of the display means, internal battery holder means and one or more slots to hold card modules or a base unit which houses a minimum of the display means, internal battery holder means which employs a set of self contained slide / clip together modules with interconnection means to allow these modules to clip / slide together securely and communicate information between the modules, the combined modules forming a larger more complex self contained unit, the functionality of the modular PDA being determined by the choice of card modules or self contained slide I clip together modules, these card modules or self contained modules implementing fixed functions and or have programmable and or reconfigurable logic means allowing the function of the card module or self contained module to be changed in either real or non-real time, the user being able to construct a personal design assistant apparatus from the various card modules or self contained clip together modules targeted at the desired application, the personal design assistant also being upgradeable and reconfigurable to existing and new applications by downloading new or upgrade software or firmware, the card modules and or slide / clip together modules providing circuitry means for implementing either or a combination of, but not limited to, the following functions:- a). memory of various types, such as FLASH to store programs and or non- volatile memory, such as SDRAM to store data, allowing the modular PDA's memory capability to be increased, b). a microprocessor, local memory and programmable logic to allow parallel operations to be performed or different hardware functions to be implemented, so the modular PDA has more processing power to enable parallel operations to be implemented, c). one or more modems, such as an Asymmetrical Digital Subscriber Line (ADSQ, g.lite or V.90 modems to allow the modular PDA to connect to the Plain Old Telephone (POTs) system for access to the Internet for example, d). a programmable communication processor which works together with the modem card module and performs segmentation and reassembly of various ATM Adaptation layers (AAL1, AAL2, AAL3/4, AAL5) for ATM traffic flow or Internet Protocols (TCP/IP) for Internet connections, the module optionally performing traffic management functions, such as traffic scheduling, traffic queuing, e). a mobile phone based on the GSM protocol or a third generation protocol, such as the Universal Mobile Telephone System (UMTS), the mobile phone card module consisting of a Radio Frequency (RF) circuitry, link control and management and baseband functions for implementing a GSIVI / third generation link, f). a card module which implements the RF circuitry, link control and management and baseband functions for implementing a Bluetooth link and or a HomeRF link and or a Wireless ATM (WATM) and or a IEEE 802.11 Wireless Local Area Network (WLAN) link, to allow the modular PDA to communicate with wireless peripherals and or other wireless units, g). a card module which implements Analogue to Digital Converters (ADCs) and or Digital to Analogue Converters (DACs) and or digital interfaces for data acquisition applications, h). a card module which implements a television receiver and or Teletex decoder circuitry so the user can access and view this information on the modular PDA's screen, i). a Digital Audio Broadcast (DAB) decoder and or FM, MW, LW radio receiver, j). a video and audio processing card module, for example based on MPEG2 and or MPEG 4 to allow a video input to be coded and transmitted and received via the mobile phone card or allow MP3 audio to be decoded, processed and played by the user, k). circuitry that allow the modular PDA to be configured as a virtual test instrument, for example measuring voltages, current, resistance, 1). Global Positioning System (GPS) decoder, m). signal generation circuitry for generating various test waveforms at a wide range of frequencies for use in on-site testing of equipment to allow the modular PDA to be configured as a virtual test instrument, n). circuitry which implements voice recognition functions which allows the user to communicate with the modular PDA applications without the use of a keyboard means.

2. Apparatus as claimed in Claim 2 in which the card modules and or self contained slide / clip together modules have programmable interfaces based on programmable logic, for example Field Programmable Logic Arrays (FPGAs) so upgrades can be easily implemented by changing the configuration of the programmable logic to implement different interface standards of the associated card module.

3. Apparatus as claimed in any preceding claim in which the modular PDA base unit contains any combination of the following: - a microprocessor, associated local memory, program memory, peripheral interfaces and a crystal to generate the desired system clocks.

4. Apparatus as claimed in any preceding claim in which the modular PDA base unit as external power supply means.

14.

5. Apparatus as claimed in any preceding claim in the modular PDA base unit has integrated circuitry to implement any combination of the following interfaces, antenna means for use with any mobile phone communication protocol, infra-red communication link, such as IrDA, a Universal Serial Bus (USB) interface, UART, Firewire interface, a IEEE1284 interface.

6. A modular PDA as claimed in any preceding claim which employs a card module or self contained clip-together module to implement local ad-hoc wireless links for communicating with peripherals, such as a headset to allow video / graphics data and or voice data to be transmitted to and received from the modular PDA.

7. A modular PDA as claimed in Claim 6 in which the wireless modules implement either the Bluetooth \Wreless protocol, the HomeRF wireless protocol, Wireless ATM (WATM) or the IEEE 802.11 wireless local area network protocol or any combination of these protocols and the apparatus can optionally implement interoperability between the different protocols to allow communication between disparate equipment.

8. A modular PDA as claimed in any preceding claim which implement voice recognition means so a user can enter text data using a voice to text encoder.

9. A modular PDA as claimed in any proceeding claim which has an integrated keyboard for entering alpha-numeric characters required by the associated application.

10. A modular PDA as claimed in any preceding claim which has connection means to allow a keyboard or keypad to be connected to the modular PDA for entering alpha-numeric characters required by the associated application.

11. A modular PDA as claimed in any preceding claim wherein a pen means is employed to select items and or enter text information via the display means.

12. A modular PDA as claimed in any preceding claim which can be configured for use as a navigation aid and or receive traffic information and rely this to the user, the apparatus optionally being connected to a cradle from which obtain power and connect to external antenna means, the apparatus being used in automobiles, boats and aircraft.

13. Apparatus as claimed in any preceding claim wherein the apparatus has Internet access, via modem card module means, allowing the user to download upgrade firmware or software for implementing new access and or communication protocols and or signal processing algorithms allowing the programmable logic and processing elements in the card modules or slide / clip together modules to be reconfigured to implement the new algorithms, the new firmware and software being stored in non-volatile memory which is accessible by the host processor, the Internet access also allows the user to download audio information, such as MP3, Mich can then be processed by is.

the apparatus before being output to other apparatus, such as a wireless headset.

14. A modular PDA as claimed in any preceding claim wherein the card modules or slide / clip together modules communicate with each other and the host processor in the base unit, if provided, via switching means, the switching means being a cross bar switch or a self-routing switch, optionally with priority queuing means, the data being passed between the card modules is of fixed length packets or optionally variable length packets, the paths between the switch and a card module or slide / clip together module being preferably serial links, but parallel links can be employed, the paths for cross bar switch being configured by the host processor.

15. A modular PDA as claimed in any preceding claim wherein the apparatus employs one or more card module or clip / slide together modules which implement authentication and encryption circuitry to allow secure communications of data.

16. A modular PDA as claimed in Claim 15 wherein the modular PDA can be configured as an electronic wallet allowing the apparatus to be credited and debited with monetary token so the apparatus can be used in financial transactions.

17. Apparatus as claimed in any preceding claim wherein the card modules incorporate 'Plug and Play' means to allow a card module to configure and initialise itself and interact with the host processor means to indicate the configuration, status and functionality of the card module.

18. Apparatus as claimed in any preceding claim wherein the card modules incorporate the means to be hot swappable allowing card module insertion or removal from the apparatus card frame while the apparatus is operational.

19. A modular and reconfigurable personnel design assistant apparatus substantially as described herein with reference to Figures 1 - 7 of the accompanying drawings.