Systems and methods for a multi-platform wireless modem

A standard interface for interfacing a wireless modem assembly with a host device comprises a primary serial interface, a secondary serial interface, and a differential serial interface for supporting communication between the wireless modem assembly and the host device. The standard interface can be implemented in a standardized connector, such as a 70-pin connector having unused pins for future feature expansion. The standard interface also provides for other interfaces including, for example, power, modem status, audio, voice, general purpose input/output, and subscriber identification.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to wireless data communication and, more particularly, to systems and methods for a multi-platform wireless modem.

Wireless communication and portable computing are converging. As a result, many portable computing devices incorporate a wireless modem for data communication. A wireless modem uses wireless communication channels to replace a more traditional wired connection through, for example, a telephone or a cable line. Also, in order to meet an increased demand for wireless data communication, wireless system operators have developed a variety of data communication protocols to support wireless data communication within their systems. Unfortunately, this has resulted in a plurality of incompatible data communication systems and protocols.

The plurality of systems and protocols creates problems for wireless modem manufacturers, because a wireless modem manufacturer must design a different modem for each communication system and/or protocol. Making matters worse for the manufacturer, different portable computing devices may require the wireless modem to have a specific form factor. Each portable computing device may also define a different software protocol for communication between the computing device and the wireless modem. As a result, the wireless modem manufacturer may have to design a different wireless modem assembly for each type of communication protocol and each type of portable computing device. The duplication creates excess cost for the manufacturer and makes changing or upgrading modems difficult for the user.

For purposes of this specification and the claims that follow, the term wireless communication protocol is used to refer to both the air interface standard used by the wireless modem to access a communication channel in a particular communication system and to the communication protocol used by devices in the system to communicate with each other. Common air interface standards include Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), as defined for example by the IS-136 specification, Global System for Mobile (GSM) communications, and Code Division Multiple Access (CDMA) as defined for example by the IS-95 specification. There is also a world wide effort to consolidate the different wireless communication protocols into a single standardized protocol known as third generation or “3G”.

Despite efforts to achieve convergence in the so-called3G communication protocols, however, there is still considerable confusion in the market-place. The confusion is made worse by numerous proprietary, non-standard protocols in use in a variety of systems, and even when a standard protocol is used differences in implementation between offerings from multiple modem vendors, or between those from a single vendor, make transitioning between vendors and/or technologies difficult for the end user. As a result, the concept of seamless replacement is not available to the end user or system integrator, which results in added cost, frustration, and delayed time-to-market, as well as reduced competitiveness in the market place.

SUMMARY OF THE INVENTION

In order to combat these problems, the systems and methods for a multi-platform wireless modem provide for standardization of a wireless modem in several key areas as well as the ability to seamlessly configure the wireless modem to implement different communication protocols and/or air interface standards.

Some key areas of standardization include: a standard form factor, a standard core module that comprises a baseband section and an RF section, a standard software protocol for communication between the wireless modem and a host device, a standardized interface between the standard core module and the host device, and standard methods for power management.

Configurability is achieved by configuring the core module to be removable. This way, the wireless modem can be configured for different communication protocols and/or air interface standards by removing and replacing the core module. Additionally, certain aspects of the software protocol and the power management methods are left undefined so that they can be customized for a particular implementation.

Further features and advantages of this invention as well as the structure of operation of various embodiments are described in detail below with reference to the accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

1. Standard Core Module

FIG. 1illustrates a wireless modem assembly100in accordance with the systems and methods for a multi-platform wireless modem. Assembly100comprises a core module102and an interface112for interfacing assembly100to a host device114in which assembly100is installed or with which assembly100is connected. Core module102can further comprises SIM card support116, RF section104having antenna connector108, and baseband section106configured to support one or more advanced features110, explained in detail below.

The systems and methods for a multi-platform wireless modem provide a future-proofed multi-technology, multi-platform strategy that provides standardization across the following primary areas:Physical form-factor;Standard host interface;Software protocol;RF connection, including support for future antenna technologies; andPower management.

The standardization is achieved through the combination of core module102and interface112. Interface112is preferably configured to provide a standard interface between assembly100and host device114. This greatly simplifies the complexity of designing a core module102, because it can be designed for one standard interface, regardless of the type of host device114. Interface114is discussed more fully below.

Core Module102also preferably enables standardization in terms of different end-user form-factors, different user interfaces, and different host platforms as well as standardization across different communication protocols. Such standardization is achieved using cross-technology standardization principles in the design of different core modules102intended for different applications. By incorporating these principles into the design of different core modules102, they preferably become interchangeable. Therefore, a single wireless modem assembly100can easily be configured for different environments by simply swapping out one core module102for another. For example, if wireless modem assembly100is switched form a Cellular Digital Packet Data (CDPD) environment to an Enhanced Data GSM Environment (EDGE) environment, all that is needed is to switch core module102from a CDPD module to an EDGE module.

This standardization, however, goes beyond designing each core module102so that it can plug into the same socket or connector in assembly100. For example, each module102is preferably configured to communicate over a standard interface112as opposed to each module102being configured for a device specific interface. As will be explained below, standardization of interface112also preferably requires that the software communications protocols used to communicate over interface112be standardized. Therefore, each core module102only needs to be configured to support one communication protocol for communicating with host device114. The standardization principles further include future-proofing provisions designed to enable backward-compatible customizations for future modules with smaller form-factors, that supports new wireless communication protocols, and that support greater power (current) requirements, new software features, future antenna technologies, future power management features/algorithms, etc. Therefore, future wireless modem assemblies100can reduce the impact and cost of migrating to a new technology, form factor, etc., by being configured to use core modules102.

As described above the standardization principles address the shortcomings of current solutions by permitting migration from one communication protocol or technology to another via removal of one core module102and simple replacement with another module102. The physical replacement of a core module102will generally require a host software protocol upgrade to accommodate new or enhanced features and/or protocols specific to a given host device114, and may require an increase in power (current) supplied to assembly100. Such changes are generally recognized to be significantly easier than a redesign of the physical interface to support different form-factors, features, possibly connectors, etc., which is required by conventional migration techniques.

Moreover, the standardization described allows the manufacturer to significantly streamline his manufacturing efforts, thus providing significant costs savings. Essentially, the manufacturer can build one standard wireless modem assembly100instead of a different assembly100for each different application. The manufacturer will then need to build different core modules102as required for different applications. But by implementing the standardization principles described, variations in the manufacturing process for these different modules102is minimal. Thus, overall manufacturing cost are reduced. Moreover, in some embodiments, the standardization in design of core modules102allows a wireless modem assembly100to be reconfigured for a different application via software reconfiguration of core module102, which enables such advantages as over the air reconfiguration of assembly100.

In order to facilitate replacement of core module102, assembly100preferably includes a standard connector or socket (not shown) configured to receive core module102. This, of course, requires that core module102include the correct type of interface in terms of both hardware and software for interfacing with the standard connector. Core module102also preferably conforms to a standard form factor. This allows the use of a standard connector as discussed. It also is another factor in easing migration from technology to technology or from one type of host device114to another.

RF Section104and baseband section106are discussed in detail in the following sections. RF section104is responsible for interfacing wireless modem assembly100to other devices over a wireless communication channel. Baseband section106is responsible for communicating information from host device114to those other devices, and vice versa, once assembly100is connected to them over the communication channel. In the sections that follow various other aspects of assembly100are discussed, with specific attention to how the design of assembly100is standardized in accordance with the systems and methods described herein.

a. The RF Section

RF section104comprises a transceiver used to transmit and receive RF signals over a wireless communication channel in accordance with the appropriate air interface standard. An example transceiver200is illustrated inFIG. 2. Transceiver200is split into a transmit and receive path. The transmit path comprises a modulator202that modulates baseband signals from baseband section106(seeFIG. 1) with an RF carrier204in order to generate an RF transmit signal. RF carrier204is a sinusoidal carrier signal with a frequency equal to that required by the communication channel used by modem assembly100to communicate with other devices. The transmit path of transceiver200may also include a Power Amplifier (PA)206. PAs are typically key components in any high frequency RF transmitter design. This is because RF transmitters typically require high output power to compensate for path losses and to achieve satisfactory signal levels at the antenna connected to antenna connector108(see Figures).

The receive path of transceiver200comprises a demodulator208that modulates a received RF signal with RF carrier204in order to remove the carrier and extract the baseband information signal. The receive path may also include a Low Noise Amplifier (LNA)210. The RF signals received by the antenna are typically at very low signal levels. Therefore, a LNA210is used to amplify the signal level, but not introduce noise that could swamp the low level received signal.

The receive and transmit paths are typically duplexed over a common connection, e.g., antenna connector108, to the antenna216. The impedance of the connection, however, needs to match the impedance of the antenna for the antenna to transmit the RF transmit signal efficiently. If the impedance is not matched, then RF energy will be reflected back in the opposite direction when a transmit or receive RF signal reaches the connection. Therefore, a matching network212can be included in order to match the impedance between the connection and the antenna. Typically, for example, the connection will have impedance of 50 ohms. Therefore, the matching network needs to adjust the impedance of the antenna to be reasonably close to 50 ohms at the signal frequency.

RF section104also includes an antenna connection108for connecting wireless modem assembly100to whatever antenna is being used. As part of the standardization principles discussed above, antenna connection108is preferably a standard connector used for all air interface standards that assembly100can be configured to implement. This significantly reduces design complexity by allowing a standard connector to be selected for all possible configuration of assembly100, which saves manufacturing time and cost. It also allows for easy reconfiguration of assembly100by simply installing the appropriate core module102and the appropriate antenna. Moreover, depending on the implementation, it can also allow for module102to be reconfigured for a different air interface via a software reconfiguration and installation of the appropriate antenna into connector108. This ability substantially streamlines the manufacturing process and even allows for reconfiguration of assembly100in the field.

Differences in air interface standards and in host devices, however, can make it difficult to have a common antenna connection for all possible configurations of assembly100. These differences require that in some instances, a different antenna type must be used depending on the configuration. Differences in antenna types prevent the use of a standard connector for several reasons. First, direct antenna connections are generally custom designed for the specific antenna type. Second, different antennas will require different tuning, which will not only impact the type of connector, but can also impact the design of RF section104. Moreover, regulatory requirements for some host devices preclude using a standard connector for all configurations. Preferably, however, wireless modem assembly100comprises an antenna connector108that is reusable for as many configurations as possible, thus permitting the use of a broad range of antenna solutions including internal, external, and patch antennas. Further, with the advent of third generation (3G) wireless systems, it may be even more practical to use a common antenna and therefore a common antenna connector108.

Regardless of what connector is used, it is also preferable for assembly100to have a standard location for antenna connector108in accordance with the standardization principles discussed. In this manner, design time and cost can be saved. Moreover, a set location ensures that antenna connector108does not interfere with the ability to reconfigure a particular wireless modem assembly100for a new Wireless communication protocol and/or air interface standard. In one embodiment, for example, connector108comprises a single MMCX connector located in one corner of the RF portion of core module102.

A second antenna may be required depending on what advanced features are supported by assembly100. For example, if assembly100supports Bluetooth™ or Global Positioning System (GPS) applications, then a second antenna may be needed. A secondary antenna connection can be located elsewhere and is not necessarily limited by the location of antenna connector108. Preferably, however, assembly100also comprises a standard location for any secondary antenna connector that may be required. As with antenna connector108, a standard location for secondary antenna can save time and cost.b. The Baseband Section

FIG. 3illustrates an example embodiment of a baseband section300. Baseband section300comprises a Control Processing Unit (CPU) and/or a Digital Signal Processor (DSP), such as CPU/DSP302, which controls the operation of baseband section300. Baseband section300also includes a memory304for storing application software used by CPU/DSP302to operate baseband section300. Memory304can also store data used by baseband section300. Baseband section300can also includes a voice codec306. Voice codec306is used to encode and decode voice information. Therefore, if assembly100is capable of communicating voice as well as data, voice codec306can be included in baseband section300.

Baseband section300is responsible for communicating with a host device, such as host device114. Baseband section106takes information from host device114and encodes it into a baseband signal that is passed to an RF section, such as RF section104, for transmission over a communication channel to another device. Conversely, baseband section300also takes baseband signals from RF section104and decodes them into signals that can be sent to host device114. In order to communicate with host device114, baseband section300must be capable of implementing a software protocol that host device114can interpret. Preferably, a wireless modem assembly100designed in accordance with the systems and methods for multi-platform wireless modem, and in particular with the standardization principles discussed above, implements a standard host communication protocol for communication with a host device114. Preferably, the host communication software protocol primarily comprises an AT command set that includes both technology-agnostic as well as technology specific AT commands. Again, such standardization saves design time and cost, because each core module102can be designed to implement the same software protocol.

Communication with host device114is preferably controlled by a communication device, such as a Universal Asynchronous Receiver Transmitter (UART)308as illustrated inFIG. 3. Further, the software used by baseband section300to implement the host communication protocol for communicating with host device114is preferably stored in memory304.

The encoding and decoding of baseband signals communicated between baseband section300and RF section104is performed by CPU/DSP302. In order to correctly encode and decode the baseband signals, baseband section300must be configured to support the appropriate wireless communication protocol for the wireless communication system. The software used by baseband section300to implement the communication protocol is also preferably stored in memory304. The appropriate communication protocol is dictated by, or is part of, the air interface standard being implemented. Some example communication protocols that can be supported are CDPD, Metricom/Ricochet2, General Packet Radio Service (GPRS)/GPS, EDGE, CDMA 1×RTT (Real Time Technology), CDMA 3×RTT, and CDMA HDR (High Data Rate).

Significantly, because of the standardization employed by the systems and methods for a multi-platform wireless modem, reconfiguration of a wireless modem assembly100to support a new communication protocol can be done quickly, efficiently, and with very little customization, merely by replacing core module102, and possibly the antenna included in assembly100. Alternatively, in some embodiments core module102can be reconfigured for a new communication protocol via a software reconfiguration due to the implementation of the standardization principles discussed. Again this can significantly streamline the manufacturing process and can even allow over the air reconfiguration for units in the field.

The design of baseband section300can also include advanced feature support310that allows wireless modem assembly100to capture applications such as MPEG audio layer 3 (MP3), Moving Picture Experts Group (MPEG)-4, Musical Instrument Digital Interface (MIDI), Digital-Voice for voice recognition, voice-to-text and text-to-voice conversion, voice memo/recording, GPS, Bluetooth™/W-PAN (Wireless-Personal Area Network), Wireless-Local Area Network (WLAN), etc.FIG. 3shows, schematically, the support for future advanced features. The objective ofFIG. 3, in this regard, is to demonstrate that when an advanced feature110is implemented, baseband section300makes available the data appropriate to this “feature” to CPU/DSP302. Further, appropriate application software stored, for example, in memory304can then enable CPU/DSP302to support the advanced feature.

From the perspective of interface112, inFIG. 1, these advanced features are preferably supported by the connection scheme with host device114. Preferably, the advanced features are supported in interface112only to the extent that they do not require an excessive number of dedicated hardware interface signals. To ensure adequate support for advanced features, however, interface112preferably includes at least limited future flexibility in the form of reserved or undefined (NoConnect/NC) interface signals. Another option available for assembly100implementations is the addition of hardware external to assembly100that can route the “advanced feature” data across interface112to host device114. This is discussed in detail in the next section.

Therefore, implementing the standardization principles described in designing core module102allows the manufacturing process to be streamlined, thus saving time and cost. Reconfiguration of fielded units is also easier and less time consuming. Notably, implementation of the standardization principles can even allow for software reconfiguration of wireless modem assembly100either in the factory or in the field. This can have important cost savings implications. For example, in the factory, the manufacturing process an be streamlined by designing one core module102, and therefore one assembly100. At the end of the process, each core module102, or assembly100, can be configured for the appropriate application via a software configuration step. Similarly, fielded assemblies can be quickly and easily reconfigured by interfacing them to a computer and downloading the appropriate software. In some embodiments, over the air reconfiguration can also be implemented.

2. Modem Interface Device

FIG. 4illustrates a wireless modem assembly400that includes a wireless interface device406that interfaces interface112and host device114. Core module102communicates to host device114through interface112as before, however, modem interface device406can be required for a variety of reasons. One reason device406can be required is to convert from the standardized interface of interface112to a host specific interface for host device114. Another reason is that device406can be used to add to or expand the functionality of assembly400, which is more clearly demonstrated by the example embodiment of a modem interface device500illustrated inFIG. 5. Modem interface device500comprises UART502, memory504, CPU/DSP506, and advanced feature set508.

Several advantages accrue as a result of including modem interface device500. For example, as data services continue to evolve, modem designs will likely not have sufficient CPU/DSP processing power for execution of the extensive user/application code that will be required. This is primarily due to the overhead involved in simply managing the air interface. Further, in certain embodiments extensive processing power within assembly400is undesirable for reasons of cost efficiency. Therefore, additional functionality including processing, CPU/DSP506, and/or application memory504can be provided by including them in a modem interface device500.

Additionally, if extensive application processing is performed within assembly400itself, the execution speed may be impacted by a relatively slow serial interface between assembly400and host408. This can be another reason to include a modem interface device, such as device500. For example, even if the fastest Universal Serial Bus (USB) speeds, e.g., 12 Mbps of USB 1.1, are available, execution speed can still be impacted. Therefore, additional CPU/DSP506and/or memory504added in a modem interface device500can be used to prevent a relatively slow serial interface at the output of assembly400from precluding more powerful implementations.

Such “co-processing” capability is a powerful extension of the capabilities of assembly400. For example, if an even higher-speed serial connection is required between assembly400and host device408, then the compatible USB 2.0 interface can, for example, be supported by including the appropriate resources in modem interface device500. Moreover, instead of including support for advanced features110in assembly100, such support can be included in modem interface device500as illustrated by advanced feature support508.

Thus, a modem interface device, such as devices406and500, can allow for a streamlined manufacturing process even when particular applications require specialized features and/or resources. Wireless modem assembly400can still be designed in accordance with the standardization principles discussed above, which will provide all of the benefits described, and any application specific features can be incorporated into a modem interface device. Therefore, the manufacturing process for different assemblies400can be substantially the same, the only difference being what type of modem interface device is used. Support for varying features can of course result in differences in the application software as well, but accommodating these differences through the combination of application specific hardware and a specific modem interface device is much easier than accommodating them through design differences in assembly400.

3. Power Management

Another aspect of the standardization principles discussed above is power management. Preferably, therefore, baseband section106also implements a standard power management scheme. To support this power management scheme, interface112preferably includes a standard power supply from host device114. For example, a nominal 3.6V supply supporting 3.3V LVTTL signaling can be used. In addition, there is preferably a standby power source from host device114to assembly100.

Preferably, the power management scheme is divided into three categories: network (air-interface) based, host (operating system) based, and internal-modem-specific based. Network power management is specific to the air-interface standard, and includes power saving methods such as the Quick Paging channel in a CDMA2000™ System. An example of host/operating-system based power management is that which applies to the Personal Computing Memory Card Interface Association (PCMCIA) standards, which include reference to the Advanced Configuration and Power Interface (ACPI) standard. An example of an internal modem-specific power savings feature may be shutting off certain parts of the assemblies electronics based on rules not covered by network or host protocols, or as specifically demanded by the user and implemented by modem assembly100.

Again, the design and manufacture of assembly100can be streamlined by implementing the standardized power management described above because it avoids the burden of incorporating differing power management schemes into assembly100. It also simplifies the design of standard interface112, because it does not need to support a variety of power management signals and protocols. Nor does it need to be changed or reconfigured to support such differing signals and protocols.

As illustrated inFIG. 1, support for the GSM Subscriber Identity Module (SIM) card116can be provided within assembly100. Interface112can accommodate this support depending on whether SIM card116is “external” or “internal”. Thus, the SIM116can take the following forms:i. External. The SIM signals are sent to host device114, which manages SIM card116ii. Internal. Assembly100is provided with an “internal” SIM module116, extracting SIM signals from interface112and driving a SIM cardholder that is preferably mounted on assembly100.

Further, support for the CDMA/ANSI-136 Replaceable Universal Identity Module (R-UIM) (not shown) is also preferably provided via shared use of the SIM signals of interface112. The R-UIM standard is backward compatible with the SIM standard.

5. Standard Form Factor

Another area of standardization that is preferably included in wireless modem assemblies designed in accordance with the systems and methods for a multi-platform wireless modem is the form factor of assembly100. Preferably, each wireless modem assembly100is designed in accordance with one of two standardized form factors. In the first of these form factors, the width of the modem is approximately 54 mm, the length is approximately 72.9 mm, and the thickness is approximately 5.6 mm. The second standard form factor is intended to be compatible with the compact flash form factor. Accordingly, this form factor has a width of approximately 42.8 mm, a length of approximately 36.4 mm, and a thickness of approximately 5.6 mm. It should be noted, however, that some or all of these dimensions may need to change depending on the requirements of a particular implementation. Further, other standardized form factors are clearly contemplated and within the scope of the SIM's described herein. It is also preferable that each of these standard form factors also specifies a location for a connector that implements interface112.

Again, by standardizing the form factor, the manufacturing process can be made less costly and time consuming. In addition, upgrading or changing wireless modem assemblies100is made easier because the new modem will have the same form factor and host interface112. Thus, if a user wanted to upgrade his wireless data service, for example, the user could simply install the requisite software and then simply swap the old assembly100for the appropriate new assembly100. This makes upgrading, or migrating from one technology to another easier and less costly, which is a benefit to consumers, system integrators, and manufacturers.

6. Standard Interface

Preferably, assembly100comprises a standard interface112. In other words, regardless of what type of device assembly100is interfacing with, one aspect of the systems and methods for a multi-platform wireless modem is that interface112can use a standard interface. Thus, the design of wireless modem assemblies110is simplified if designed in accordance with the systems and methods for a multi-platform wireless modem.

As noted, because there are many possible host devices, not all of which are compatible with interface112, wireless modem assembly100may need a modem interface device500to convert interface112to an interface required by host device114. Moreover, some devices114may require that a host-specific interface be used. For example, in wireless modem assemblies100designed for insertion into a PCMCIA slot, standard interface112can be replaced by the standard PCMCIA interface. Alternatively, a modem interface device500can be used to convert interface112to the PCMCIA interface.

Standard interface112includes several serial data interfaces for interfacing a host device114to a wireless modem assembly100. These serial data interfaces are illustrated, interfacing host device114and modem assembly600, as serial data interface608,610, and612inFIG. 6. Preferably, interface608is a primary Recommended Standard-232 (RS232) serial data interface, known as Port A. Port A preferably supports the following signal set: TXD, RXD, CTS, RTS, DTR, DSR. If interface112supports serial data interface612, then support for Port A is desired but not required.

Additionally, interface112preferably supports a secondary RS232 serial data interface, known as Port B. Port B preferably comprises the two signals TXD2and RXD2. Port B can be used within the module in one of two ways. The standard use of610a, designated Port B1, is for internal peripheral device606communication. This can be used, for example, for communication with a device such as a GPS receiver. In this case, the signals TXD2and RXD2are signals internal to wireless modem assembly600and do not appear on interface112. An alternate use comprises interfaced610b, designated Port B2, utilizes the same two signals and forms an interface to host device602. In this case, the signals can be multiplexed with two General Purpose Input/Output (GPIO), which are discussed below. Port B2or Port B1preferably supports a minimum rate of 38.4 kbps, and a rate of 115 kbps is preferable. Further, interface112preferably includes optional support for a USB serial data interface, known as Port C116. Support for Port C is provided via two signals included in interface112, USB+ and USB−, which form a differential signal pair. Preferably, Port C supports a minimum rate of 2.5 Mbps, which is necessary, for example, to support the IMT-2000/3G data rates. If Port C is present, it preferably forms the primary communication interface for WAN data between modem assembly600and host114. If there is no Port C support, then by default Port A serves as the WAN data communication transport.

Preferably, Port A and/or Port C support the maximum serial data rates required by the communication protocols implemented by baseband section106, plus a nominal 10% overhead. If Port A cannot support the desired rate, then Port C can be selected. Further, If Port C supports the maximum data rates, then Port A need only support a minimum rate of 38.4 kbps, but a rate of 115 kbps is preferable.

In addition to serial data interfaces608,610, and612, interface112also preferably includes the following interfaces between host device102and modem600: power and ground interfaces to modem assembly600, a wireless modem status interface, at least one ADC input to modem assembly600, a power standby input to modem600, a JTAG interface between host device114and modem assembly600, and a GPIO interface, comprising a plurality of GPIO inputs/outputs. The GPIO interface preferably comprises as many GPIO signals as possible within the constraint of a reasonable connector total pin count. Interface112also preferably provides a SIM interface configured to provide a data communication interface between host device114, or wireless modem assembly604, and a SIM card (not shown) included in wireless modem assembly600. There is also preferably an audio interface configured to provide a buzzer output to host device114, a speaker output to host device114, a microphone input to wireless modem assembly600, and a digital voice interface between host device114and wireless modem assembly600. Other interfaces or signals that can be included in interface112include: support for at least one ADC input, support for a “standby” power source from the host602to modem assembly600, and support for a JTAG (IEEE 1149) interface.

Interface112is typically embodied in a standard connector. Preferably, the connector is a 70-pin connector. 70-pins allows enough pins to cover the features described, with an adequate amount of pins left over for future expansion. One example connector that can be used is SMK's CPB7270-1211 (Mtype) connector. The following tables provide an example pin description for interface112implemented in a 70-pin connector. Note that the actual pin numbers are by way of example only.

TABLE 1Pin Assignments by FunctionDirectionPin(with respectPower-onNumberNameto the modem)Reset StateDescriptionBasic function interface28, 29, 30, 31VCC1Power—Power Supply Connection to theModem for all Circuitry Except forthe RF Power Amplifier18, 19, 20, 21,VCC2Power—Power Supply Connection to the22, 23, 24, 25Modem for the RF Power AmplifierOnly6, 8, 9, 11, 17,GNDPower—Modem Signal and Chassis Ground26, 27, 42, 48,60, 61, 7059PWR_INDOutput—Power Indicator:HIGH: Indicates that the modem is onLOW: Indicates that the modem is off57SM_INDOutput—Sleep Mode Indicator:HIGH: Indicates that the Modem is onLOW: Indicates that the modem is off58WKUPInput—Wake up Input: (Active High Pulse)Refer to Applications informationfor more details.56DTMInput—Data to Modem: (3.3 V Logic Level)In RS-232 terms, this is called “TXD”55DFMOutput—Data From Modem: (3.3 V Logic Level)In RS-232 terms, this is called “RXD”51RTSInput—Ready to Send: (3.3 V Logic Level)52CTSOutput—Clear to Send: (3.3 V Logic Level)54DTRInput—DTE Ready: (3.3 V Logic Level)53DSROutput—DCE Ready: (3.3 V Logic Level)49GPIO1Bi-directionalInput withGeneral Purpose ConfigurablePullupInput or Output: Refer to the ATcommand set for the Default State50GPIO2Bi-directionalInput withGeneral Purpose ConfigurablePullupInput or Output: Refer to the ATcommand set for the Default State47GPIO3Bi-directionalInput withGeneral Purpose ConfigurablePulldownInput or Output: Refer to the ATcommand set for the Default State46GPIO4Bi-directionalInput withGeneral Purpose ConfigurablePullupInput or Output: Refer to the ATcommand set for the Default State45GPIO5Bi-directionalInput withGeneral Purpose ConfigurablePulldownInput or Output: Refer to the ATcommand set for the Default State44GPIO6Bi-directionalInput withGeneral Purpose ConfigurablePullupInput or Output: Refer to the ATcommand set for the Default State5ADC_IN1Analog InputADC InputADC Input: This pin is connected toone channel of an ADC.SIM Interface36VCC_SIM (C1)Power—Power Supply For the SIM/R-UIMmodule34DATA_SIM (C7)Input/Output—Data to and From the SIM/R-UIMmodule32CLK_SIM (C3)Input—Clock to the SIM/R-UIM39RST_SIM (C2)Input—Reset to the SIM/R-UIM37SPARE_SIM (C8)TBD—Spare SIM/R-UIM signal (future)35SPARE_SIM (C4)TBD—Spare SIM/R-UIM signal (future)33SIM_NOT_INInput—Indicator for SIM/R-UIM presenceAudio Interface2MIC_INPInput—Positive differential input for themicrophone (analog voice)4MIC_INNInput—Negative differential input for themicrophone (analog voice)3SPKR_OUTPOutput—Positive differential output for thespeaker (analog voice)1SPKR_OUTNOutput—Positive differential output for thespeaker (analog voice)15DIGVOICE_TXOutput—Digital Serial Voice Output13DIGVOICE_RXInput—Digital Serial Voice Input12DIGVOICE_CLKOutput—Digital Voice Clock10DIGVOICE_FRMOutput—Digital Voice Frame16BUZZEROutput—Buzzer OutputMiscellaneous14VCC_STANDBYPower—Input Power for Standby of the Modem7ADC_IN2Input—ADC Input: This pin is connected toone channel of an ADC.43GPIO7Bi-directionalInput withGeneral Purpose Configurable InputPullupor Output40GPIO8Bi-directionalInput withGeneral Purpose Configurable InputPullupor Output41GPIO9Bi-directionalInput withGeneral Purpose configurable InputPulldownor Output38GPIO10Bi-directionalInput withGeneral Purpose Configurable InputPulldownor Output:62, 63, 64, 65,FutureTBDTBDTBD66, 67, 68, 69

TABLE IIPin Assignments by Pin NumberDirectionPin(with respectPower-onNumberNameto the modem)Reset StateDescription1SPKR_OUTNOutput—Positive differential output for thespeaker (analog voice)2MIC_INPInput—Positive differential input for themicrophone (analog voice)3SPKR_OUTPOutput—Positive differential output for thespeaker (analog voice)4MIC_INNInput—Negative differential input for themicrophone (analog voice)5ADC_IN1Analog InputADC InputADC Input: This pin is connected toone channel of an ADC.6GNDPower—Modem Signal and Chassis Ground7ADC_IN2Input—ADC Input: This pin is connected toone channel of an ADC.8GNDPower—Modem Signal and Chassis Ground9GNDPower—Modem Signal and Chassis Ground10DIGVOICE_FRMOutput—Digital Voice Frame11GNDPower—Modem Signal and Chassis Ground12DIGVOICE_CLKOutput—Digital Voice Clock13DIGVOICE_RXInput—Digital Serial Voice Input14VCC_STANDBYPower—Input Power for Standby of the Modem15DIGVOICE_TXOutput—Digital Serial Voice Output16BUZZEROutput—Buzzer Output17GNDPower—Modem Signal and Chassis Ground18VCC2Power—Power Supply Connection to theModem for the RF Power AmplifierOnly19VCC2Power—Power Supply Connection to theModem for the RF Power AmplifierOnly20VCC2Power—Power Supply Connection to theModem for the RF Power AmplifierOnly21VCC2Power—Power Supply Connection to theModem for the RF Power AmplifierOnly22VCC2Power—Power Supply Connection to theModem for the RF Power AmplifierOnly23VCC2Power—Power Supply Connection to theModem for the RF Power AmplifierOnly24VCC2Power—Power Supply Connection to theModem for the RF Power AmplifierOnly25VCC2Power—Power Supply Connection to theModem for the RF Power AmplifierOnly26GNDPower—Modem Signal and Chassis Ground27GNDPower—Modem Signal and Chassis Ground28VCC1Power—Power Supply Connection to theModem for all Circuitry Except for theRF Power Amplifier29VCC1Power—Power Supply Connection to theModem for all Circuitry Except for theRF Power Amplifier30VCC1Power—Power Supply Connection to theModem for all Circuitry Except for theRF Power Amplifier31VCC1Power—Power Supply Connection to theModem for all Circuitry Except for theRF Power Amplifier32CLK_SIM (C3)Input—Clock to the SIM/R-UIM33SIM_NOT_INInput—Indicator for SIM/R-UIM presence34DATA_SIM (C7)Input/Output—Data to and From the SIM/R-UIMmodule35SPARE_SIM (C4)TBD—Spare SIM/R-UIM signal (future)36VCC_SIM (C1)Power—Power Supply For the SIM/R-UIMmodule37SPARE_SIM (C8)TBD—Spare SIM/R-UIM signal (future)38GPIO10Bi-directionalInput withGeneral Purpose Configurable InputPulldownor Output: Refer to the AT commandset for the Default State39RST_SIM (C2)Input—Reset to the SIM/R-UIM40GPIO8Bi-directionalInput withGeneral Purpose Configurable InputPullupor Output: Refer to the AT commandset for the Default State41GPIO9Bi-directionalInput withGeneral Purpose Configurable InputPulldownor Output: Refer to the AT commandset for the Default State42GNDPower—Modem Signal and Chassis Ground43GPIO7Bi-directionalInput withGeneral Purpose Configurable InputPullupor Output: Refer to the AT commandset for the Default State44GPIO6Bi-directionalInput withGeneral Purpose Configurable InputPullupor Output: Refer to the AT commandset for the Default State45GPIO5Bi-directionalInput withGeneral Purpose Configurable InputPulldownor Output: Refer to the AT commandset for the Default State46GPIO4Bi-directionalInput withGeneral Purpose Configurable InputPullupor Output: Refer to the AT commandset for the Default State47GPIO3Bi-directionalInput withGeneral Purpose Configurable InputPulldownor Output: Refer to the AT commandset for the Default State48GNDPower—Modem Signal and Chassis Ground49GPIO1Bi-directionalInput withGeneral Purpose Configurable InputPullupor Output: Refer to the AT commandset for the Default State50GPIO2Bi-directionalInput withGeneral Purpose Configurable InputPullupor Output: Refer to the AT commandset for the Default State51RTSInput—Ready to Send: (3.3 V Logic Level)52CTSOutput—Clear to Send: (3.3 V Logic Level)53DSROutput—DCE Ready: (3.3 V Logic Level)54DTRInput—DTE Ready: (3.3 V Logic Level)55DFMOutput—Data From Modem: (3.3 V Logic Level)In RS-232 terms, this is called “RXD”56DTMInput—Data to Modem: (3.3 V Logic Level)In RS-232 terms, this is called “TXD”57SM_INDOutput—Sleep Mode Indicator:HIGH: Indicates that the Modem is onLOW: Indicates that the modem is off58WKUPInput—Wake up Input: (Active High Pulse)Refer to Applications informationfor more details.59PWR_INDOutput—Power Indicator:HIGH: Indicates that the modem is onLOW: Indicates that the modem is off60GNDPower—Modem Signal and Chassis Ground61GNDPower—Modem Signal and Chassis Ground62FutureTBDTBDTBD63FutureTBDTBDTBD64FutureTBDTBDTBD65FutureTBDTBDTBD66FutureTBDTBDTBD67FutureTBDTBDTBD68FutureTBDTBDTBD69FutureTBDTBDTBD70GNDPower—Modem Signal and Chassis Ground