BlackBerry R902M-2-O Wireless Data Modem User Manual Revised copy of Integrator Manual

BlackBerry Limited Wireless Data Modem Revised copy of Integrator Manual

Contents

Revised copy of Integrator Manual

Integrator’sGuideRIM 902MOEM Radio Modem
RIM 902M OEM Radio Modem Integrator’s GuideLast Updated: January 11, 1999Model No. R902M-2-O© 1999, RESEARCH IN MOTION LIMITEDResearch In Motion and RIM are registered trademarks of Research In Motion Ltd.Mobitex is a trademark of the Swedish Telecommunications Administration.MS-DOS is a registered trademark, and Windows is a trademark, of Microsoft Corp.Warning: This document is for the use of licensed users only. Any unauthorisedcopying, distribution or disclosure of information is a violation of copyright laws.While every effort has been made to ensure technical accuracy, information in thisdocument is subject to change without notice and does not represent a commitment onthe part of Research In Motion Limited.Research In Motion295 Phillip StreetWaterloo, OntarioCanada N2L 3W8tel. (519) 888-7465fax (519) 888-7884E-mail: rim902m@rim.netWeb site: www.rim.netMOBITEX Interface, specifiedin SpecificationLZBA 703 1001,compatible equipment
FCC Compliance Statement (USA)FCC Class B Part 15This device complies with Part 15 of FCC Rules. Operation is subject tothe following two conditions:1. This device may not cause harmful interference, and2. This device must accept any interference received, includinginterference that may cause undesired operation.WarningChanges or modifications to this unit not expressly approved by the partyresponsible for compliance could void the user’s authority to operate thisequipment.This equipment has been tested and found to comply with the limits for aClass B digital device, pursuant to Part 15 of the FCC Rules. These limitsare designed to provide reasonable protection against harmfulinterference in a residential installation. This equipment generates, usesand can radiate radio frequency energy and, if not installed and used inaccordance with the manufacture’s instructions, may cause harmfulinterference to radio communications.There is no guarantee, however, that interference will not occur in aparticular installation. If this equipment does cause harmful interferenceto radio or television reception, which can be determined by turning theequipment off and on, the user is encouraged to try to correct theinterference by one or more of the following measures:• Re-orient or relocate the receiving antenna.• Increase the separation between the equipment and receiver.• Connect the equipment into an outlet on a circuit different fromthat to which the receiver is connected.• Consult the dealer or an experienced radio/TV technician forhelp.
Industry Canada CertificationThis device complies with Industry Canada RSS 119, under certification numberTBD.IC Class B complianceThis device complies with the Class B limits for radio noise emissions as set outin the interference-causing equipment standard entitled “Digital Apparatus,”ICES-003 of Industry Canada.
ContentsFCC Compliance Statement (USA)..........................................iIndustry Canada Certification.................................................iiAbout this guide....................................................................... v1. Introduction................................................................. 1Radio performance ......................................................................... 1Mobitex network technology.......................................................... 4FCC radio frequency exposure rules .............................................. 52. Getting started............................................................. 9Test board overview..................................................................... 10How to connect the test board ...................................................... 11The MENU diagnostics tool......................................................... 133. Mechanical integration ............................................. 21Environmental properties ............................................................. 21Physical properties........................................................................ 22Mounting methods........................................................................ 24Cables and connectors.................................................................. 274. Power requirements ..................................................31Load specifications....................................................................... 31Batteries........................................................................................ 32Plug-in supplies ............................................................................ 34Automotive supplies..................................................................... 345. Interface specification............................................... 35MASC and RAP link-layer protocols ........................................... 35Pin descriptions ............................................................................ 37How to turn the radio on and off .................................................. 42Interface to an RS-232 device ...................................................... 43Interface to microprocessor .......................................................... 436. Antenna selection....................................................... 45Selecting an antenna..................................................................... 45
Introduction to antenna terminology............................................. 46Positioning the antenna................................................................. 48Shielding....................................................................................... 49Specifications ......................................................................... 51Glossary of terms................................................................... 53Index....................................................................................... 55
About this guideThis document is a guide to integrating the RIM 902M OEM radio modem into avariety of devices such as laptop computers, handhelds, vending machines,point-of-sale terminals, vehicle-based mobile terminals, and alarm system.Topics covered in this guide include:• mounting requirements• power (battery) characteristics• interfacing to the RIM 902M• antenna selection and placementThroughout the guide, there are suggestions and precautions that will ease theimplementation of a wireless communication solution. These recommendationsare based on years of experience integrating wireless modems into a variety ofdevices. You are welcome and encouraged to contact RIM if you would like todiscuss the technical implementation of this radio modem.
11. IntroductionWith the introduction of the RIM 902M, Research In Motion (RIM) has set anew standard for radio modem performance. The RIM 902M is unrivalled in thekey areas of receiver sensitivity, output efficiency, noise immunity, and powerconsumption. Its small size and weight make it suitable for virtually any wirelessdata application, including handheld devices and mobile terminals.The RIM 902M is designed for use with Mobitex wide-area wireless datanetworks operating in the 900 MHz range, such as the BellSouth IntelligentWireless Network.RIM radio modems are specifically designed to integrate easily into a computeror other embedded system. Potential applications include:• Laptop computers • Vehicle tracking and location• Point of sale devices • Monitoring and telemetry• Ruggedized terminals • Vending machines• Handheld PC’s • Utility meters• Parking meters • Billboards• Dispatching • Security alarm panelsRadio performanceThe RIM 902M offers the highest performance of any radio modem for Mobitexwireless data networks:
2 Introduction – Radio performanceIntegrator’s Guide – RIM 902M OEM Radio ModemReceiver sensitivityReceiver sensitivity is a measure of how well a radio modem can “hear” anetwork base station. This figure is important when a device will be used in areaswhere signal strength is weak, such as inside buildings and in locations that arenot close to a base station. A radio modem with good receiver sensitivity can beused in more places than a radio modem with poor sensitivity.The RIM 902M has a receiver sensitivity of –118 dBm, or 0.0016 picowatts.This is the strength of the weakest digital signal that can be interpreted with a1% bit error rate. Although 1% may seem high, the sophisticated over-the-airMobitex protocol corrects these errors before the data is passed to theapplication, ensuring error-free communication. This capability is already builtinto the radio’s firmware, and does not require any additional softwaredevelopment.Noise immunityThe RIM 902M is not de-sensitized by the electromagnetic interference (EMI) or“noise” that is generated by the electronics of the terminal into which it isintegrated. As a result, no special shielding is required between the radio andyour device.Noise immunity offers several benefits, including:• easier integration • improved RF performance• longer battery life • more coverage from each base station• increased reliability • no need for special RF shieldingPowerful and efficient transmitterWhen necessary, the RIM 902M can supply a full 2.0 watts to the antenna.However, the RIM 902M quickly decreases the output power when it is close toa base station − to as little as 0.06 watt – because a stronger signal is needed onlywhen far from a base station. By transmitting a strong signal only whennecessary, the RIM 902M conserves battery power.The RIM 902M provides reliable transmit efficiency across the entire operatingvoltage range of 4.15 to 4.75 volts. As a result, batteries can be used even whennearing depletion. This also maximizes the radio coverage area throughout thelife of the battery.
Introduction – Radio performance 3RIM 902M OEM Radio Modem – Integrator’s GuideLow power requirementsIf you are planning to integrate the RIM 902M into a handheld or portabledevice, battery life is a critical issue: your customers will insist on long lastingdevices without heavy battery packs. The RIM 902M sets a new powerconsumption standard for Mobitex radio modems. This ensures efficiency andmaximizes battery life.Transmitting data: 1.7 amps or less (at 4.5V), depending on output powerThe transmitter is ON for a pulse of between 32 ms and 1 second perpacket, depending on the amount of data transmitted. The maximum packetsize for a Mobitex device is 512 bytes.Receiving data: 60 mA (at 4.5V)The radio turns its receiver ON for a 150 ms “window” once every 10seconds. The base station will only attempt to communicate with the radioduring this window. To minimize latency during rapid two-waycommunication, the receiver is also turned ON and kept ON for 10 secondsafter any communication (transmit or receive) with the network.Standby power: 0.3 mA (at 4.5V)Standby power consumption is very low and occurs when no radio activityhas taken place for at least 10 seconds. The radio and base station areclosely synchronized to ensure that a communication attempt is not missedwhen the radio is in standby mode.Battery life is not a concern for certain applications, such as in-vehicleapplications that draw power from the vehicle battery. For these applications, itis possible to put the radio in an express operating mode, in which powerconsumption is higher than normal but packet transfer latency is reduced to aminimum.Small sizeUsing a single board design, the RIM 902M is very thin, and much smaller thana business card, at only 42.0 by 67.5 mm. This tiny size allows the RIM 902M tomeet tight space requirements within most applications. The fact that a singleboard is used means that the device is much more reliable than multi-boarddesigns, particularly in high-vibration environments such as vehicles.
4 Introduction – Mobitex network technologyIntegrator’s Guide – RIM 902M OEM Radio ModemMobitex network technologyThe Mobitex wireless network technology, developed by Eritel in 1984 forSwedish Telecom, has become an international data communication standard.Now managed by the Mobitex Operators Association (MOA), which controls thespecifications for this open standard, Mobitex is a secure, reliable, wirelesspacket switching network specifically designed for wide-area wireless datacommunications.Mobitex networks are deployed around the world. The technology is presentlyavailable in the following countries:• Australia • Germany • Singapore• Austria • Indonesia • Sweden• Belgium • Italy • Turkey• Canada • Korea • United Kingdom• Chile • Netherlands • United States• Finland • Norway • Venezuela• France • PolandMobitex networks in the United States, Canada, Korea, Chile, and Venezuelaoperate in the 900 MHz range, and are therefore directly compatible with theRIM 902M OEM radio modem. Currently, Mobitex networks in other countriesoperate at other frequencies, such as 400 MHz.Mobitex provides highly reliable, two-way digital data transmission. Thenetwork provides error detection and correction to ensure the integrity of thedata being sent and received, and includes transmission acknowledgment.The Mobitex network has a hierarchical structure that allows messages to berouted from sender to receiver along the most direct path possible. Each radiocell is served by an intelligent base station. Because intelligence is distributedthroughout the network, data is only forwarded to the lowest network nodecommon to the sender and the receiver. For example, one base station is able tohandle all traffic in its coverage area.The network constantly monitors the location of the mobile users. As a mobilemoves from one area of coverage to another, base stations track its signals,sending updated mobile location and status information to the network. If thenetwork goes down at any point in transmission, the message is held untilnetwork service is restored. If the mobile receiver moves outside the coveragearea, the base station stores the data until coverage is re-established, then
Introduction – FCC radio frequency exposure rules 5RIM 902M OEM Radio Modem – Integrator’s Guideforwards it to the mobile. This prevents data loss, and increases the reliability oftransmission.Mobitex is optimized for data communication. It uses a packet switchingtechnique to provide the greatest flexibility in data transmission. Conventionalcellular phone systems, by contrast, use a circuit-switched network, in which aphysical connection is created between the sending and receiving nodes, andmust be maintained throughout the duration of the transmission. With circuit-switched systems, the set-up time for establishing a connection involvessignificant overhead and airtime cost, especially when only a small amount ofdata needs to be transferred.Mobitex packets include information about the origin, destination, size, type, andsequence of data to be sent. This enables packets to be transmitted individually,in any order, as traffic permits. Internal to the network, individual packets maytravel along different routes, in any order, without interfering with other packetssent over the same frequency by different users. At the receiving end, all packetsare accounted for, and reassembled into the original message.Set up time is eliminated and network connection is instantaneous. As a result,packet-switching makes far more efficient use of channel capacity, typicallyallowing 10 to 50 times more users over a radio channel than a circuit switchednetwork.FCC radio frequency exposure rulesBased on FCC rules 2.1091 and 2.1093(1) and FCC Guidelines for HumanExposure to Radio Frequency Electromagnetic Fields, OET Bulletin 65 and itsSupplement C(2), all integrations of the RIM 902M OEM unit are subject toroutine environmental evaluation for RF exposure prior to equipmentauthorization or use.For portable devices, defined in accordance with FCC rules as a transmittingdevice designed to be used within 20 cm of the user body under normaloperating conditions, RF evaluation must be based on Specific Absorption Rate(SAR) limits in Watts/kg. SAR is a measurement of the rate of energyabsorption per unit mass of body tissue.For mobile devices, defined as a transmitting device designed to be generallyused such that a separation distance of at least 20 cm is maintained between thebody of the user and the transmitting radiated structure, the human exposure to
6 Introduction – FCC radio frequency exposure rulesIntegrator’s Guide – RIM 902M OEM Radio ModemRF radiation can be evaluated in terms of Maximum Permissible Exposure(MPE) limits for field strength or power density in mWatts/cm2.Warning: For an end product not covered by RIM MPE testing and submission,the integrator will submit for a separate FCC ID. It is mandatory for portable endproducts such as hand-held and body-worn devices to comply with FCC RFradiation requirements with respect to SAR limit.The submission should include end product information, end product SAR/MPEtest report and a reference to RIM module FCC ID for all other Part 90requirements. RIM will submit module specific information and test reports for ageneric MPE compliance.The three specific antennas tested with the RIM 902M radio modem for genericMPE compliance are Larsen NMO 3E 900B with 3 dBd gain, Austin 200160500C with 0 dBd gain and Eclipse II Magnet Mount 3 dBd gain antenna. TheMPE passing distance for the Larsen ground plane bolted antenna adjusted to 6foot cable length, is 23 cm. And the passing distance for both Austin groundplane bolted and Eclipse II ground magnet mount scaled to 6 ft cable is 20 cm.The vehicular integrators of RIM 902M who use the Larsen, Austin or Eclipse IIantennas, will be in compliance with MPE limit, provided that the antennas areinstalled at least 23 cm for Larsen and 20 cm for Austin or Eclipse II antennasfrom any edge of a vehicle rooftop.The vehicular device integrators using these antennas would be required to add aprominent warning in their user manuals to instruct the installer/end user onproper antenna mounting and antenna centering on the vehicle rooftop incompliance with MPE separation distance. Also the operator/user should bewarned to maintain the minimum required distance from antenna at all times.Integrators using the above antennas in the vehicular configurations, do notrequire separate FCC approval for RF exposure compliance with respect to MPElimits. However, the integrators of vehicular devices who use antennas other thanthe three tested by RIM or integrators of portable devices, would then berequired to do separate MPE testing for vehicular/mobile applications and SARtesting for handheld/portable devices. This would require submitting for aseparate FCC ID and going through the appropriate process.SAR and MPE limitsSAR limits for General Population/Uncontrolled exposure is 1.6 W/kg for partialbody exposure, averaged over 1 g of tissue and 4 W/kg for hands, wrists, feetand ankles averaged over 10 g of tissue. The limits for Occupational/Controlledexposure are more relaxed, i.e., 8 W/kg for partial body and 20 W/kg for hands,
Introduction – FCC radio frequency exposure rules 7RIM 902M OEM Radio Modem – Integrator’s Guidewrists, feet and ankles. The 1.6 W/kg limit applies for most of RIM OEMintegrators.The limit for MPE is 0.6 mW/cm2 at 900 MHz.GuidelinesRF exposure distance is based on normal operating proximity to the user’s ornearby persons’ bodies. This distance is measured from any part of a radiatingstructure, which is generally the antenna to the closest body part. A set of testneeds to be performed to determine the passing distance that meets the exposurelimits with respect to SAR for hand held/body worn/portable devices and MPEfor vehicular/mobile devices if antennas other than the three tested by RIM areused.Operating manual compliance statementFor the mobile/vehicular transmitter, the integrators should include a statementin their operation/user/installation manual making the user aware of RF exposureissues and insuring that the users keep a passing distance from the antenna whiletransmitting. The integrators of mobile end products, should provide instructionsor diagrams in the manual for proper antenna mounting and positioning, whenapplicable, to ensure a safe exposure distance to the operator and nearbypersons.For portable transmitters, separate FCC approval is required to be in compliancewith FCC RF exposure guidelines in respect to the SAR limits.LabelIf the minimum separation distance of the final device configuration can not bemet due to occasional non-essential operating conditions or requirements, thenthe device needs to have an RF radiation hazard label warning the user or nearbypersons to keep away from the antenna by the specified distance.
Compliance with respect to SAR limits which satisfy MPE limits, would notrequire warning labels, however, an RF radiation warning label can be used toalert the user or nearby persons about abnormal usage conditions.Warning to Integrators and UsersTo meet the FCC RF exposure requirement for mobile transmitter end productsusing the Larsen NMO 3E 900B, 3 dBd antenna, ensure that the antenna is atleast 23 cm away from the user or nearby persons when transmitting.This statement should be added by all integrators to their user manual along withproper installation instructions. The installation instructions should include, butare not limited to, the correct mounting procedures on a ground plane, andpositioning the antenna such that the minimum 23 cm is kept from any edge ofthe vehicle rooftop.22. Getting startedRIM is committed to facilitating the integration of the RIM 902M OEM radiomodem. We provide the necessary resources to evaluate the feasibility ofimplementing a wireless communication solution, and work closely with ourpartners to develop an application in the shortest time possible.Years of intense R&D have spawned several tools that have been used internallyto help streamline our own development process. We have included many ofthese tools with the RIM 902M OEM Developer’s Kit. The purpose of the Kit isto accelerate radio integration and to help system designers evaluate theRIM 902M. Using the Kit, you can quickly begin interfacing the radio modem toyour computing device.We’re here for you!RIM has a team of experienced engineers who can support you in the design andimplementation of your project. If you need help getting started, or if you haveany questions about the radio technology or its integration into your platform,please contact the RIM 902M engineering development team:
10 Getting started – Test board overviewIntegrator’s Guide – RIM 902M OEM Radio Modeme-mail: rim902m@rim.netphone: +1 (519) 888-7465fax: +1 (519) 888-7884web: www.rim.netTest board overviewThe RIM test board provides a standard RS-232 serial interface between a PCand the radio modem. It is designed to help you quickly interface the RIM 902Mto a standard PC (through a COM port) or a terminal device with an RS-232serial port. The test board also provides access points to the radio’s serialcommunication port, which allows you to monitor activity with a logic probe,multimeter, or oscilloscope.The test board includes the following components and functionality:RS-232 interfaceThe serial (COM) port on a PC and most terminal devices operates at RS-232signal levels, which are typically ±12V. This high voltage would damage theRIM 902M, which is typically integrated into a device that operates anasynchronous serial port at 3.0V. The RS-232 interface on the test board allowsyou to produce an output from the radio that is easily interpreted by a PC.Test pointsThe test board is more than just an RS-232 interface. It also features debuggingfacilities to help you test your application. It provides direct access to each of the22 pins on the serial data cable, which allows connectivity to analyticalequipment (e.g. logic probe, multimeter, or oscilloscope) and real-timeindication of data flow.
Getting started – How to connect the test board 11RIM 902M OEM Radio Modem – Integrator’s GuideOn/off switchWith the switch in the ON position, the radio will turn on whenever power isapplied to the test board. When the switch is moved to the OFF position, theradio will shut down.Power supplyThe RIM 902M must be provided with a clean, high-current power source. Inthis case, we use a standard plug-pack to provide the current necessary to operatethe radio. The voltage is converted into the necessary levels by the power supplysection on the test board.LED indicatorsThe test board includes several LED indicators designed to indicate the flow ofdata to and from the host (in real time), the radio power status, power to the testboard, and more.How to connect the test boardNow that you are familiar with the components and functions of the test board,you are ready to connect the RIM 902M radio modem to an antenna and to a PC(or some other computing device with an RS-232 serial interface). To do this,you will use the test board and cables supplied with your RIM 902MDeveloper’s Kit.
12 Getting started – How to connect the test boardIntegrator’s Guide – RIM 902M OEM Radio Modem1. Flat serial cable (test board to radio)The flat serial interface cable carries data between the test board and theRIM 902M. Control and status signals such as TURNON are also carried on thiscable. Use this cable to connect the RIM 902M’s serial connector to the testboard.This cable also carries clean, regulated power to the RIM 902M.When inserting the cable, ensure that the side with the bare pins is in directcontact with the pin side of the connector.2. DB-9 serial cable (test board to PC)Connect the male end of the straight-through DB-9 serial cable to the test board.Connect the female end of the cable to your PC’s COM port.3. Power adapter (test board to AC outlet)Plug the 120VAC-to-12VDC power adapter into the wall outlet. Connect theother end to the power jack of the test board.4. Antenna cable (radio to magmount antenna)Your developer’s kit includes a high-performance, 6dB-gain magmount antenna.This antenna is terminated with a screw-on SMA plug. The RIM 902M radiomodem includes a snap-on MMCX jack. The antenna cable supplied with yourdeveloper’s kit connects the antenna’s SMA plug to the radio’s MMCX jack.The magmount antenna provides the best RF performance when placed on abroad metal surface, such as the roof of a car. When used inside a building,performance is improved if the antenna is located near a window, with fewobstacles (wall, furniture, equipment, etc.) between the antenna and the window.The antenna performs equally well if it is positioned upside down.
Getting started – The MENU diagnostics tool 13RIM 902M OEM Radio Modem – Integrator’s Guide5. Turn the system onThe power switch on the test board is connected to the TURNON line of theRIM 902M radio modem. To determine whether the radio is on, look at the LEDmarked ONI. It is lit when the radio is on.The MENU diagnostics toolNow that you have successfully connected your RIM 902M radio modem to yourPC, you are ready to send a test packet through the Mobitex network.Your radio modem should be activated by the network operator in order to beused on the Mobitex network and to establish an airtime agreement. If you havenot already arranged for activation of your radio, contact your network operator.The RIM 902M contains a diagnostic utility called MENU. With this utility, youcan set the current network, “ping” your radio modem, or view radio andnetwork status values.SetupThe following instructions assume that your RIM 902M is connected to a PCrunning a terminal program, such as Windows HyperTerminal. The MENUutility is based in the RIM 902M’s firmware, so HyperTerminal is the onlysoftware required to use it.The MENU utility’s user interface is a full-screen text mode interface, and usesthe ANSI cursor command set. Programs like HyperTerminal support the ANSIcodes by default. If you are using a different terminal program that does notprovide ANSI cursor control, the MENU utility will drop into a line-by-lineinterface. The appearance of the line-by-line interface is not documented here,but the commands it uses are the same as those described below.Select the COM port which communicates with the RIM 902M and configure for9600 bps, and either 7E1 (7 bits, Even parity, 1 stop bit) or 8N1 (8 bits, Noparity, 1 stop bit). If you have set this up correctly, you will see bursts ofcharacters from the radio modem such as ^0010B 47E,0:5D. These characterbursts are normal; they represent a MASC B frame, which you can ignore fornow.
14 Getting started – The MENU diagnostics toolIntegrator’s Guide – RIM 902M OEM Radio ModemType the word menu (all in lower case letters only) then press the ENTER key.You can expect to see a full screen of information. If nothing happens, simply re-enter menu until the radio modem responds. The word “menu” itself willprobably not appear on the screen as you type it in.If you re-enter menu and nothing occurs, ensure that the radio is turned on andconnected to the PC, and that all cables are securely connected. Please contactRIM for assistance if you are stuck at this point.Once the utility has been started, the terminal program’s screen will look similarto the following:RIM 902M Firmware Version 1.0.0(c) 1999 Research In Motion LimitedRadio Setup Radio Serial Number = 031/11/066300Command Key Description Networks Available:----------- ----------- -------------------Q Quit and reset the radio. 1. RMDUS (B433/B433) 2. CANTEL (C4D7/C4D7)N Set the current network.P Ping: Send a Status MPAK to yourself. Your Choice ?MAN=16231144 RSSI= 40% 24 dBuV Battery= 97% Network=RMDUS (B433/B433)Contact=Yes Mode=PowerSave Live Tx=Enabled Active=Yes Group List=BornUpFreq=02FF DoFreq=0F2F Base/Area=14/0A Status=0080The screen displays the software version and build date, the radio modem’sserial number, the list of available Mobitex radio networks, current radio modemstatus indicators, the “ping” function, and other relevant information.RSSI stands for Received Signal Strength Indicator. This is a measure ofnetwork coverage. The higher the number, the better the coverage. The RSSI isgiven both as a percentage and in dBµV (decibel microvolts). To obtain theRSSI in dBm (decibel milliwatts), subtract 113 from the dBµV value. Note thatRSSI= 0% 0 dBµV does not necessarily represent the complete absence of asignal; in many cases, the radio is capable of communicating with the network atsignal strengths of 0 dBµV or even less. Actual contact with the Mobitexnetwork would be indicated by the Contact field. The RSSI is updated every tenseconds, or whenever you press D.
Getting started – The MENU diagnostics tool 15RIM 902M OEM Radio Modem – Integrator’s GuideThe Battery indicator shows the level of supplied voltage. The battery level isupdated once every thirty seconds, or whenever you press D.Network tells you which network you are currently using. The example showsRMDUS (BellSouth Wireless Data, formerly RAM Mobile Data, operates aMobitex network in the United States) and CANTEL (Cantel AT&T operates aMobitex network in Canada).MAN stands for Mobitex Access Number, which is a unique number thatidentifies each Mobitex radio modem. The MAN is used for addressing packets.The screen will also display a Radio Serial Number, which is unique to eachradio modem. This number is often referred to in other documents as ESN(Electronic Serial Number) or MSN (Mobitex Serial Number).Mode shows whether the radio is in powersave mode or express mode. Thedefault operating mode is powersave, which reduces power consumption by theradio but introduces a latency of up to 10 seconds when receiving packets fromthe network. This mode may be changed through software.Tx is an indicator to let you know whether the radio’s transmitter is enabled ordisabled. The transmitter may be enabled or disabled through software, and isnormally enabled. The Mobitex base station may also instruct a radio to shutdown (also referred to as DIE) if it is an illegal device, or not registered, orcausing disruption to the Mobitex network. The word Live on the status lineindicates that the radio is not in a DIE state.A radio modem receives a Group List when it is powered up and registers withthe network base station. Normally, you would see Group List=OK, whichindicates that the radio has successfully signed onto a base station. If you seeGroup List=Born, then either your device is out of coverage, or it has not beenactivated by your network operator. Note that it can take 30 seconds for a radioto display Group List=OK.UpFreq and DoFreq show the channels (in hexadecimal) that you are using totransmit and receive, respectively. If you are interested in obtaining the exactcurrent transmit frequency, divide UpFreq by 80 and add to 890. This gives avalue in MHz. Add 39 MHz to obtain the receive channel. For example, if thedisplay reads “UpFreq=02FF DoFreq=0F2F” then convert hexadecimal 02FF todecimal 767, divide by 80 and add to 890, and obtain 899.5875 MHz, which isthe transmit channel. Add 39 MHz (or repeat the calculation using DoFreq) todetermine that the receive channel at 938.5875 MHz.Base/Area indicate which base station you are using. Every base station in thenetwork is assigned a unique Base/Area combination. Base stations in the same
16 Getting started – The MENU diagnostics toolIntegrator’s Guide – RIM 902M OEM Radio Modemgeographic area often share an Area address. Contact your network operator ifyou want to know the location of network base stations.Status describes the current state of the radio. Other documentation may alsorefer to the Status value as the radio’s internal fault bits. The following tableshows the interpretation of the Status bits. If the Status value displayed on yourscreen does not correspond to any of the values below, then determine whichvalues add together in hexadecimal to give the Status value that you see. Forexample, status value B403 would simultaneously describe states A000, 1000,0400, 0001, and 0002, as described below.0000 The radio modem status is normal. There are no warnings.0001 The RIM 902M has been out of coverage for a long time. No adequate basestation was found. Possible causes include lack of network coverage, wrongnetwork selected, or the battery level is too low.0002 This is a new RIM 902M being used for the first time. No action is necessary.0008 The radio modem has exhausted its internal memory. This should not happenunder ordinary use. Turning the radio modem off and back on will resolve this.0020 The network has issued a DIE command to the radio modem, perhaps because itis not registered on the network. No data can be sent to the network until a LIVEcommand is issued by the network. Contact the network operator for help.0040 The modem’s transmitter has been disabled by your software, using either theMASC “F M0” or RAP “Turn Transmitter Off” command. The transmitter canbe turned back on with the MASC “F M1” or RAP “Turn Transmitter On”command, or by resetting the radio.0080 The radio modem has not yet received a grouplist from the network. If this bitremains set after the modem has been in network coverage for several minutes,your radio modem is probably not activated. Contact the network operator toactivate your device.0100 Another device may be using the same MAN number as your device on the samebase station. This should not happen under ordinary use. It may cause duplicate,dropped, or mixed up packets. Contact the network operator to determinewhether two units have the same MAN number.0800 The RIM 902M may be having a problem remembering its last base station. Ifthe problem persists, the unit should be returned for repair.1000 The RIM 902M has received an unknown interrupt and might be havingproblems receiving packets. If the problem persists, the unit should be returnedfor repair.2000 The RIM 902M has received an unknown interrupt. No action is necessary.4000 The RIM 902M has been damaged and cannot be used until this problem iscorrected. The unit should be returned for repair.
Getting started – The MENU diagnostics tool 17RIM 902M OEM Radio Modem – Integrator’s GuideHow to change to a different networkThe RIM 902M radio may be used on different Mobitex networks operating ondifferent channels in the 900 MHz range. Up to 16 network channel lists may beprogrammed by RIM into each radio. If the network shown is not the correctone, you can choose another from the list of networks available. Press N and theMENU utility will present an additional prompt for selecting the network, asshown below.RIM 902M Firmware Version 1.0.0 release(c) 1999 Research In Motion LimitedRadio Setup Radio Serial Number = 031/11/066300Command Key Description Networks Available:----------- ----------- -------------------Q Quit and reset the radio. 1. RMDUS (B433/B433) 2. CANTEL (C4D7/C4D7)N Set the current network.P Ping: Send a Status MPAK to yourself. Your Choice ? Choose a network from the list (1..2) ?MAN=16231144 RSSI= 30% 22 dBuV Battery= 97% Network=RMDUS (B433/B433)Contact=Yes Mode=PowerSave Live Tx=Enabled Active=Yes Group List=BornUpFreq=02FF DoFreq=0F2F Base/Area=14/0A Status=0080Change network nameYou may now enter a number corresponding to the desired network shown underNetworks Available. When you press Enter, the radio modem will switch to theselected network, as shown below. If you do not enter a number, or if you erasethe number you have typed, then no change will occur when you press the Enterkey. Pressing the Esc key will cancel the network set-up command.The screen below shows what would happen if you typed in 2 and then pressedthe Enter key. The values shown beside Network, UpFreq, DoFreq, andBase/Area are different.
18 Getting started – The MENU diagnostics toolIntegrator’s Guide – RIM 902M OEM Radio ModemRIM 902M Firmware Version 1.0.0(c) 1999 Research In Motion LimitedRadio Setup Radio Serial Number = 031/11/066300Command Key Description Networks Available:----------- ----------- -------------------Q Quit and reset the radio. 1. RMDUS (B433/B433) 2. CANTEL (C4D7/C4D7)N Set the current network.P Ping: Send a Status MPAK to yourself. Your Choice ?MAN=16231144 RSSI= 45% 25 dBuV Battery= 97% Network=CANTEL (C4D7/C4D7)Contact=Yes Mode=Fallback Live Tx=Enabled Active=No Group List=BornUpFreq=030D DoFreq=0F3D Base/Area=1B/09 Status=0080Radio update was successful.“Ping” the network: an end-to-end radio testYou can determine whether your radio modem is working on the network bypressing P. When you “ping,” you send a message (MPAK – Mobitex datapacket) to yourself via the wireless network base station. The MENU utility willdisplay a message indicating that the MPAK was sent. A few seconds later, itshould also indicate that the MPAK was received. This confirms that your radiomodem is operational and active on the network.If you get the message “Status MPAK cannot be sent – out of coverage”, thenyou are not in an area that is covered by the Mobitex network. You candetermine whether you are in coverage by looking at Contact on the status lines.If you are certain that you are in a coverage area, but are still not able tocommunicate with the network, check the antenna to make sure it is connectedproperly and is deployed properly. Signal quality can vary significantly within abuilding. Try moving the antenna to a new location, perhaps near a window, tosee if you can get a signal.If you get the message indicating that the Status MPAK was sent, but you did notget one that it was received, then you are in coverage but your RIM 902M radiomodem has probably not been activated by your network operator, and thenetwork will not send the MPAK back to the radio. Contact the network operatorto activate your design.
Getting started – The MENU diagnostics tool 19RIM 902M OEM Radio Modem – Integrator’s GuideRIM 902M Firmware Version 1.0.0(c) 1999 Research In Motion LimitedRadio Setup Radio Serial Number = 031/11/066383Command Key Description Networks Available:----------- ----------- -------------------Q Quit and reset the radio. 1. RMDUS (B433/B433) 2. CANTEL (C4D7/C4D7)N Set the current network.P Ping: Send a Status MPAK to yourself. Your Choice ?MAN=16231227 RSSI= 11% 14 dBuV Battery=100% Network=RMDUS (B433/B433)Contact=Yes Mode=PowerSave Live Tx=Enabled Active=Yes Group List=BornUpFreq=02FF DoFreq=0F2F Base/Area=14/0A Status=0080Received MPAK from 16231227 (to 16231227) Type=03(STATUS ) Traffic/Flags=00If you are unable to communicate with the network, then contact the networkoperator to make sure that your device is activated on the network. If the radiohas not been activated, then the network will not send the MPAK back to theradio. Second, make sure that you are in network coverage. You can determinewhether you are in coverage by looking at Contact on the status lines. If itshows Contact=NO, then you are not in an area that is covered by your Mobitexnetwork. You can also determine whether the antenna is connected properly andis deployed properly. Signal quality in buildings can vary significantly over shortdistances. Try moving the antenna to a new location, perhaps near a window, tosee if you can get a signal. If none of these remedies help, contact RIM forassistance.Exiting the utilityWhen you have finished using the utility, you should press Q to quit. This step isimportant because it allows the radio to resume accepting commands from othersoftware. The screen will clear and you will be informed that the radio has beenreset. You can safely disconnect the radio and close your terminal program onceyou have seen this message.
33. MechanicalintegrationThis chapter provides information about the RIM 902M that will be useful indetermining the physical positioning of the radio modem within an application.Environmental properties and testing, physical properties, mounting methods,and connector information are presented.Environmental propertiesDuring environmental testing, RIM takes samples of its radio modems andsubjects them to a variety of harsh conditions. We measure over a hundreddigital RF calibration parameters, once before and once after each test. Thedifference between these measurements precisely reveals any performancedegradation. Each unit in the sample is also inspected visually after testing. Thisexperience allows us to fine-tune our design and manufacturing process.Environmental testing ensures that our products are able to withstand bothtypical and extreme real-world conditions in which they will be used. RIM doesnot sell units that have been subject to environmental testing.
22 Mechanical integration: Physical propertiesIntegrator’s Guide – RIM 902M OEM Radio ModemStorage temperatureThe RIM 902M OEM radio modem may be stored at a temperature from -40°Cto +85°C (-40°F to +185°F).Operating temperatureThe RIM 902M is designed to operate between -30°C to +70°C (-22°F to+168°F).The end user should be careful not to exceed the upper temperature limit of+70°C, as performance degradation or damage to the power amplifier may occurpast this point, especially when packets are transmitted frequently.Physical propertiesWeightThe RIM 902M weighs 1.2 oz (35 g), including the case.DimensionsThe RIM 902M has been designed to meet the most stringent spacerequirements. In most cases, there will be sufficient room in an existingenclosure to house the radio modem.The overall maximum dimensions of the radio modem, not including cables, are:• Width: 42.0 mm• Length: 67.5 mm• Thickness: 8.4 mm
Mechanical integration: Physical properties 23RIM 902M OEM Radio Modem – Integrator’s Guide
24 Mechanical integration: Mounting methodsIntegrator’s Guide – RIM 902M OEM Radio ModemMounting methodsThe RIM 902M OEM radio modem may be securely fastened using a variety ofmethods. The operating environment must be carefully considered whenchoosing a mounting option. For example, extreme temperature or heavyvibration may require a special mounting solution. It is important to ensure thatthe RIM 902M remains securely attached in the environment where it will beused.The following information is presented as a guide, but applications can varyconsiderably. A mechanical engineer can help ensure that the mounting methodis suitable for the specific application.BoltsThe RIM 902M radio modem includes a hole in each corner, which may be usedto bolt the device onto a circuit board, device housing, or other surface. Themounting hole pattern is four holes in a 62.5 by 36.5 mm rectangle, with eachhole 2.5 mm in diameter.The following diagram illustrates the radio mounting details.
Mechanical integration: Mounting methods 25RIM 902M OEM Radio Modem – Integrator’s GuideTie wrapsTie wraps can be used to as a secure but non-permanent means of attaching theRIM 902M to a surface. Typically, each tie wrap passes through a hole drilled
26 Mechanical integration: Mounting methodsIntegrator’s Guide – RIM 902M OEM Radio Modeminto the surface on either side of the RIM 902M. This allows the radio to beattached to a shell, a PCB, or some other mounting surface.If using tie wraps, ensure that the surface beneath the RIM 902M is flat.Otherwise, the mounting surface could push up on the bottom surface of theradio case while tightening the tie wraps pushes down on the edge of the radiocase. This could cause the metal case of the RIM 902M to flex upward and shortacross components inside the radio, causing the radio to malfunction. Forexample, thick adhesive foam tape and tie wraps should not be used together.Permanent industrial adhesiveThe RIM 902M is small and lightweight enough to be attached to the host deviceusing an industrial adhesive. For some applications, this method of mounting ispreferable to bolts, because adhesive is easier to use in a manufacturingenvironment, and is more resistant than bolts to loosening. In many cases, aneffective solution is to adhere the radio modem to the inside surface of yourproduct’s casing.An adhesive should be chosen on the basis of its ability to stick to the materialused in the outer casing of the radio modem and in the surface to which the radiowill be mounted. The bottom casing of the RIM 902M is magnesium.3M manufactures VHB, a permanent industrial adhesive with excellent long-term holding power. The peel adhesion and tensile holding power of VHB tapesare extremely high, making this a suitable solution when the radio will not needto be removed. Choose foam tape for rough surfaces and adhesive tape forsmooth surfaces.More information about VHB may be obtained by contacting 3M Industrial Tapeand Specialties Division at 1-800-227-5085 (fax: 1-612-733-1771). Thepublication number for the VHB technical data sheet is 70-0702-0266-1(104.5)R1.
Mechanical integration: Cables and connectors 27RIM 902M OEM Radio Modem – Integrator’s GuideCables and connectorsThere are two connectors on the RIM 902M radio modem. These connectorsallow interfacing from the radio modem to a serial computing device, a powersupply, and an antenna.Serial cable and connectorThe RIM 902M serial communication and control signals are carried on a flat22-conductor 0.30 mm (0.012”) thick flexible printed circuit (FPC) cable in1.00 mm centerline spacing, which can plug into a matching connector. Sinceeach application is unique, Molex can create a custom Flat Flex Cable Jumper inthe correct length and the correct connector orientation for your application. Theminimum cable length available is 30 mm (1.181”).The serial cable supplied with the RIM 902M Developer’s Kit is a Type D 4”long Flat Flex Cable Jumper in 1.00 mm centerline spacing, as illustrated in thefollowing mechanical drawing:
28 Mechanical integration: Cables and connectorsIntegrator’s Guide – RIM 902M OEM Radio ModemThis cable can plug into a matching 22-position 1.0 [0.039] horizontal FPCconnector. A variety of connectors are manufactured by Molex. Moreinformation about each connector, including mechanical drawings, is availablefrom the manufacturer’s web site (www.molex.com), or you can contact RIM(rim902m@rim.net) for help with selecting an appropriate connector for yourapplication.Contact:Molex Headquarters Molex Electronics Ltd.Lisle, IL, USA Toronto, Ontario, Canadatel: (630) 969-4550 tel: (416) 292-1444fax: (630) 969-1352 fax: (416) 292-2922www.molex.comAntenna cable and connectorsRIM selected the industry-standard MMCX connector for the RIM 902Mbecause it is a very small connector that has the mating force to withstand heavyvibration.Typically, an antenna does not plug directly into a RIM 902M. Instead, anconnector at the outer casing of the device. This allows the antenna to beremoved from the system without having to open the device, and it eliminates asource of strain on the radio’s MMCX connector.The antenna cable should have low loss, an impedance of 50 Ω, and an MMCXjack that mates with the RIM 902M’s MMCX plug. The other end of the cablecan be any connector you choose, as long as it has an impedance of 50 Ω. AnSMA screw-on connector is suitable and widely available. TNC connectors arealso suitable, but larger than SMA. The antenna cable supplied with theRIM 902M developer’s kit has an MMCX connector on one end and an SMAconnector on the other. The cable is built with strain reliefs to prevent damage.Huber & Suhner can provide antenna cables and connectors. The parts describedbelow have an impedance of 50 Ω and are suitable for use with the RIM 902M.
Mechanical integration: Cables and connectors 29RIM 902M OEM Radio Modem – Integrator’s Guide11MMCX-50-2-1C/111 Straight MMCX connector16MMCX-50-2-1C/111 Right-angle MMCX connector25SMA-50-2-25/111 SMA connectorEZ Flex 405 Low-loss matching (50 Ω) cable133REEZ4-12-S2/1216 8” cable, straight MMCX to SMA133REEZ4-12-S2/1699 8” cable, right-angle MMCX to SMAThe following cable is included with the RIM 902M Developer’s Kit:Contact:Huber & Suhner Huber & SuhnerEssex Junction, VT, USA Kanata, Ontario, Canadatel: (802) 878-0555 tel: (800) 627-2212fax: (802) 878-9880 fax: (613) 596-3001www.hubersuhnerinc.com
34. Power requirementsThe RIM 902M radio modem must be provided with a clean power sourcecapable of delivering bursts of high current. This can be provided by a plug-inpower supply unit, a rechargeable battery pack, or single use batteries. RIM hasconducted extensive research and has developed guidelines for integrators tofollow when designing the power supply system for the RIM 902M.Load specificationsThe RIM 902M draws its power in bursts; the power required changes rapidlydepending on whether the radio is transmitting, receiving, or in standby. Theload profile is given on the following page. These specifications can be givendirectly to your power supply designer or battery supplier.Power supply parametersThe RIM 902M requires a clean, stable 4.15 to 4.75 volt source that is capableof delivering a one-second burst of up to 1.7A when required by the transmitter.Under non-ideal conditions such as an improperly matched antenna, however,this burst could be as high as 2.2A. The receiver current consumption is 66 mAand the standby current consumption is 0.07 to 0.2 mA. The maximum no-load
32 Power requirements: BatteriesIntegrator’s Guide – RIM 902M OEM Radio ModemRadio load profile (at 4.5V)Transmitter ON at 2.00 W to antennaworst-case peak instantaneous (due to extremetemperature, poorly matched antenna, etc.)1.7 A2.2 AReceiver ONIn EXPRESS mode, the receiver is always ON.In POWERSAVE mode, the receiver is typicallyON for 0.15 s then OFF for 9.85 s57 mAStandby (transmitter and receiver are both OFF)Standby mode occurs for 9.85 s out of 10 s if inPOWERSAVE mode and no activity has takenplace for previous 10 s0.2 mA to5.4 mATypical average power-save current consumptiontransmit 0.17%, receive 9.74%, standby 90.09%transmit 1%, receive 5%, standby 94% 5.7 mA20.0 mATransmit durationminimummaximum 32 ms1 sOff current consumption ≤ 20 µABatteriesWhen integrated into a handheld device, the RIM 902M can be powered bybatteries. This is a proven technology that is easily available and eliminates theneed for power supply components such as voltage regulators.Rechargeable batteriesWe recommend using rechargeable nickel cadmium (NiCad) batteries to powerthe RIM 902M radio modem for battery-operated applications that require awide operating temperature range. Nickel metal hydride (NiMH) and Lithiumion (Li+) cells may also be used with good results, but many such cells do notwork very well at temperatures below freezing. Specifications for batteriesshould be obtained from the manufacturer. The RIM engineering development
Power requirements: Batteries 33RIM 902M OEM Radio Modem – Integrator’s Guideteam can help you determine whether a particular battery is suitable for yourapplication.The cells chosen must be able to meet the load specifications of the RIM 902M.Specifically, they must be able to provide 1.7 A (at 4.5V) for transmission.Rechargeable cells vary considerably, because capacity varies with current draw.Even if two cells have the same published capacity, one may not be as efficientas another when the radio transmitter is turned on. This is because some batterieshave a higher equivalent series resistance (ESR) at high current drain. The ESRshould be low enough that the battery can supply the transmit current requiredwithout a large voltage drop.Rechargeable alkaline batteries are another option. These cells are typically ratedfor about 25 discharge cycles, far fewer than NiCads, but they provide longer lifethan NiCads. For the first five to ten cycles, you will get about 70 to 80 percentof the battery life you would expect from a single-use alkaline cell. After 25discharges, this number may drop to 50 percent. Some precautions must be takenwith this type of battery. These cells are also not intended to be used to their fullcapacity, so the actual useful run-time of these cells is closer to 30 to 40 percentof a single-use alkaline cell, and requires the user to pay closer attention to thestate of the batteries. If you fully discharge a rechargeable alkaline battery, youmay only get five recharges before the capacity decreases to the point where it isuseless.Single-use batteriesAmong single-use cells, only alkaline and lithium cells provide the high currentnecessary for transmission. In particular, alkaline AA’s are inexpensive, widelyavailable, and provide an excellent power source. Alkaline cells typically runabout four times longer than similar-size NiCad cells, and about three timeslonger than similar-size NiMH cells.The use of general-purpose carbon-based batteries is not recommended, as thistype of battery is unable to supply the power required by the transmitter. If thistype of battery is used, the voltage will drop below the minimum power requiredunder load almost immediately following a radio transmit, which would reset theradio.Since carbon cells are generally sold under names like “super heavy duty,” thebest way to be sure that a single-use battery is alkaline is to look for the word“alkaline” on the label, or to use well-known brands such as Duracell orEnergizer. This should be communicated to the user of your product.
34 Power requirements: Plug-in suppliesIntegrator’s Guide – RIM 902M OEM Radio ModemPlug-in suppliesA plug-in supply converts normal AC power (usually 110 volts or 220 volts) intoa steady DC source that can be used instead of batteries. The plug-in supply mustbe designed to ensure voltage spikes, lightning, and other power fluctuationscannot damage the radio modem. Transient voltage protection zener diodes, orother spike arrestor circuits, may be added to keep the inputs within the limitsgiven in the RIM 902M load specifications. These should have a value of 20volts and be placed on the supply side of the regulator circuit.RIM recommends a supply capable of providing 4.5 V and rated for 2.5 A peakcurrent.Automotive suppliesIf you plan to power the RIM 902M from an automotive supply, extra protectionmust be included to protect the radio modem from the intense power fluctuationsexperienced when the automobile is started. A circuit comprising inductors,transorbs and voltage regulators should be used to ensure the radio modem isprotected from these power fluctuations.Commonly, in automotive applications, voltages may be as high as 70 V on thebattery, especially during starting. Commercial automotive adapters are availablethat will safely convert the 12 volt automotive supply to a regulated supplysuitable for operating the RIM 902M radio modem.
45. InterfacespecificationThe asynchronous serial interface on the RIM 902M operates at 3.0V. It issimilar to RS-232 except that 0V represents a “low” and 3V represents a “high.”This interface can be connected directly to a micro-controller, or through aUART to a microprocessor data bus.MASC and RAP link-layer protocolsThe RIM 902M requires a serial link-layer protocol to carry data, radio controlinstructions, and radio status information between the RIM 902M radio modemand the computing device to which it is attached. Two protocols are supported:Mobitex Asynchronous Communication (MASC) and Radio Access Protocol(RAP).If you are using a MASC application with another Mobitex radio and are nowmigrating to the RIM 902M, you do not need to rewrite the application in RAP –simply continue using the MASC application. If you are writing a newapplication for the RIM 902M, you will need to choose whether to use MASC orRAP as your link-layer protocol.MASC assumes a high-noise environment where bit errors are likely to occur onthe serial link between the radio modem and the computing device. MASC is
36 Interface specification: MASC and RAP link-layer protocolsIntegrator’s Guide – RIM 902M OEM Radio Modemdesigned to be extremely robust and redundant, and should be used when theserial link is unreliable or when the serial cable to the RIM 902M is very long.Advances in mobile computing technology have helped to ensure that serial linksare short enough to make bit errors extremely unlikely. This is especially true forsmaller devices such as laptops and PDAs. The complexity of MASC isunnecessary for these applications, and involves complex and lengthy softwaredevelopment.RAP was designed to take advantage of the reliability inherent to a short seriallink. The primary benefit of RAP is that it is easy to describe and implement. Asa result, RAP reduces software development time, complexity, and memoryconsumption. It also provides double the throughput of MASC, by using binaryframe data transfers instead of hex-ASCII encoding.Since every application is different, the choice of protocol should be madecarefully. The following chart is provided as a guide to comparing the relativeadvantage of each protocol.MASC RAPSerial cable betweenRIM 902M and device Designed for long serialcable prone to bit errors Assumes a short, reliableserial cableOperating environment Withstands harsh, hostileelectrical interference Best suited for laptops,PDAs, other small devicesSoftware complexity Complex SimpleImplementation time(typical) Weeks or months,or use third-party API’s DaysMemory requirements 10 to 50 kilobytes 1 to 3 kilobytesHardware flow control RTS/CTS is required RTS/CTS is optionalThroughput at 9600 bps 4800 bps 9600 bpsCost Free, open specification,or pay for third-party API’s Free, open specification,sample source code is freeThere is no “best” protocol. The MASC or RAP protocol is used strictly for thelink between the radio modem and the computing device, and does not have any
Interface specification: Pin descriptions 37RIM 902M OEM Radio Modem – Integrator’s Guideinfluence on the speed or reliability of communication between the radio and theMobitex network. The RIM engineering development team (e-mail:rim900@rim.net) can help you select the protocol most suited to your needs.Pin descriptionsAll input and output lines are 3.0 volt logic; however, they will also be able todrive 3.3 volt systems. Further, all input lines to the serial port are 5.0 volttolerant and outputs will be capable of driving 5.0 volt systems provided the VIHof these pins is less than 2.5 volts. Pins 1 through 4, the general purpose I/Olines, are strictly a 3.0 volt interface; they are not 5.0 volt tolerant.This section describes the purpose of each of the 22 lines that comprise the serialinterface of the RIM 900 OEM radio modem. The symbol ~ before the labelindicates that line is an active low digital signal.Pins 1, 2, 3, 4, 13, and 22 are designed for future use and must be leftdisconnected. All other unused inputs to the radio should be tied to ground, andany unused outputs from the radio should be left disconnected.Pin 5 ~MSG ~Message WaitingThis is an output from the radio.The active state of this line is low, and indicates that the radio has received amessage (packet) from the network, which has not been delivered to the deviceapplication yet. This line continues to remain active until the applicationacknowledges receiving the packet.When the radio’s receive buffer is full, this line will be inactive (high).
38 Interface specification: Pin descriptionsIntegrator’s Guide – RIM 902M OEM Radio ModemPin 6 ~COV ~CoverageThis is an output from the radio.The active state of this line is low, and indicates that the radio is in networkcoverage, as measured by the presence of a signal from the network base station.When the radio does not have contact with the wireless network, this line is high.Pin 9 GND GroundThis line should be tied to the system ground of the host unit to ensure properoperation.Pin 10 TURNON Turn Radio OnThis is an input to the radio.This line turns on the radio unit. It is a digital signal that eliminates the need foran on/off switch across the power supply to the radio. Information about the useof this pin is contained in the next section of this chapter.Pin 11 ONI On IndicateThis output from the radio that indicates that the radio is on and operational.This line may be used by a computing device to qualify the handshaking outputson the serial interface. If CTS is low, and ONI is high, then the unit is ready toreceive data, but if CTS is low and ONI is low, then the radio is not ready toreceive data because it is off.When ONI is low, all inputs to the radio should be held low or disconnected.Otherwise, power will be consumed and wasted.Pin 12 TRI Transmit IndicateThe active (radio transmitting) state of this line is high.
Interface specification: Pin descriptions 39RIM 902M OEM Radio Modem – Integrator’s GuideThis output from the radio that is asserted while the RIM 900 is transmitting apacket to the network base station. TRI can be used to provide real-time visualfeedback to the user that the radio is transmitting packets. If this is not necessary,the line can simply be left disconnected.This line is low when the Radio is off.Pin 14 ~RI ~Ring IndicateThis is an output from the radio.When ~DTR is not asserted (high), the RIM 900 asserts ~RI (low) to indicatethat it has data waiting for the computing device. The radio will not transfer thedata until ~DTR is asserted (low). This line can be used to wake up a suspendedcomputing device when the radio needs to communicate with it. If ~DTR isalready asserted (low) when the radio has data to send the computing device, ~RIwill not be asserted.For MASC implementations in normal serial mode, this line indicates that theradio has any MASC frame to transfer to the computing device. For MASCimplementations in interactive serial mode, this line indicates that the radio hasreceived an MPAK from the Mobitex network, and has a MASC M framecontaining the MPAK to transfer to the computing device.For RAP implementations, ~RI is not used and should not be connected. Thisline should also be disconnected if your application does not use it.Pin 15 ~CTS ~Clear To SendThis line is an output from the radio modem. The active (clear to send) state ofthis line is low.All MASC implementations require this line. This line is optional for RAPimplementations. To use hardware flow control with RAP, the radio must be ininteractive serial mode (see pin 10). Do not connect ~CTS if your applicationdoes not require it.This is an output from the RIM 900 to the computing device. This line isasserted low by the RIM 900 to indicate that it is ready to receive data from thecomputing device. When this line is high, any data sent from the computing
40 Interface specification: Pin descriptionsIntegrator’s Guide – RIM 902M OEM Radio Modemdevice to the RIM 900 may be lost. This is a flow control mechanism that isnormally reacted to by the UART in your serial communication system.When the radio is turned off, this line will be low from inside the radio modemwith an impedance of at least 20 kΩ.Pin 16 ~RTS ~Request To SendThis line is an input to the radio. Its active (request to send) state of this line islow.All MASC implementations require this line. This line is optional for RAPimplementations. Connect ~RTS to ground if your application does not requireit.This is an input to the RIM 900 from the computing device. This line should beasserted low by the computing device to indicate that it is ready to receive datafrom the RIM 900. This is a flow control mechanism that is normally handled bythe UART in your serial communication system.Pin 17 ~DSR ~Data Set ReadyThis line is an output from the radio.The active (data set ready) state of this line is low.When the RIM 900 is off, this line will be low from inside the radio modemwith an impedance of at least 20 kΩ.output from the RIM 900 that indicates thestate of DTR.Pin 18 GND GroundThis line should be tied to the system ground of the host unit to ensure properoperation.
Interface specification: Pin descriptions 41RIM 902M OEM Radio Modem – Integrator’s GuidePin 19 ~DTR ~Data Terminal ReadyThis line is an input to the radio.The active (data terminal ready) state of this line is low, and indicates that thecomputing device is ready to receive data from the RIM 900. De-asserting thisline high will turn communication off; the RIM 900 would not attempt to deliverdata to the computing device until ~DTR is again asserted low. Asserting thisline low will cause the radio to send a MASC B frame to the computing device ifMASC is the protocol being used, and will allow communication to resume.If you do not intend to use ~DTR, tie it to ground to ensure that it is alwaysasserted during radio operation.This line should be driven low when the radio is off. Driving ~DTR high whenthe radio is off will consume unnecessary power.Pin 20 TX TransmitThis line is an input to the radio. Its idle (no data) state is high.This is an asynchronous serial input to the radio unit, and should be connected tothe computing device’s Transmit Data output. This line carries data at 9600 bitsper second. MASC parameters are 7 bits, Even parity, 1 stop bit. RAPparameters are 8 bits, No parity, 1 stop bit.
42 Interface specification: How to turn the radio on and offIntegrator’s Guide – RIM 902M OEM Radio ModemPin 21 RX ReceiveThis is an output from the radio. Its idle (no data) state is high.This line is an asynchronous serial output from the radio unit, and should beconnected to the host terminal’s Receive Data input. This line carries data at9600 bits per second. MASC parameters are 7 bits, Even parity, 1 stop bit. RAPparameters are 8 bits, No parity, 1 stop bit.How to turn the radio on and offThe TURNON pin is a digital signal that turns the radio on and off. It eliminatesthe need for a power switch across the power supply to the radio.Turning the radio onTo turn the RIM 902M on, the software should first check the ONI pin. If ONI ishigh, but TURNON is being held low, then your application has recentlyrequested the radio to shut down, and the radio is performing shutdownoperations and should not be disturbed. Wait for ONI to go low beforecontinuing.If ONI is low, this indicates the radio is turned off. Set the TURNON line high toturn the radio on. The ONI pin will respond by going high, typically within 2seconds. Once the ONI pin is high, other handshaking and communicationsignals can begin.If the radio fails to respond to a high TURNON line, the radio may requireservice, or the power supplied to the radio may be too low for proper operation.Turning the radio OFFTo turn the RIM 902M off, your software should de-assert the TURNON line bysetting it low. The radio will then begin shutdown operations, and the ONI pinwill remain active until all shutdown operations are complete.
Interface specification: Interface to an RS-232 device 43RIM 902M OEM Radio Modem – Integrator’s GuideShutdown will normally require several seconds to complete, and the radioshould not be disturbed while it is shutting down. Attempting to communicatewith the radio during shutdown may extend the time taken to perform shutdownoperations. The ONI signal will be de-asserted (low) when the radio has shutdown.All serial inputs to the radio should be low when the radio is turned off. Thisensures that power consumption will be reduced to the lowest possible levels.Note that if any line is left in the high state, as much as 5 mA may flow into theradio modem.MPAK data that has been received by the RIM 902M from the Mobitex network,but which has not been transferred to the computing device, will not be saved.The MPAKs will be lost when the unit enters shutdown or is turned off.A controlled shutdown is necessary to allow the RIM 902M to tell the Mobitexnetwork that it is off air.Interface to an RS-232 deviceThe RIM 902M serial interface operates at 3.0V, making it compatible withmany existing system designs. In most cases, the RIM 902M can be connecteddirectly to a micro-controller without any additional interface logic. If the radiomodem is to be connected directly to a PC or other RS-232 device, an interfacemust be provided.Interface to microprocessorThe RIM 902M can be controlled by a wide variety of microcontrollers andmicroprocessors, such as the Intel 8051 or 80386, or Motorola 68000.A standard 8250 Universal Asynchronous Receiver/Transmitter (UART)interface may be used as the means for communicating with the microprocessor’sdata bus.
44 Interface specification: Interface to microprocessorIntegrator’s Guide – RIM 902M OEM Radio Modem
56. Antenna selectionThe antenna is one of the most important components of a wirelesscommunication system. The right antenna will maximize the coverage area of theRIM 902M.The antenna that you choose should complement the needs of your specificproject. There are many different antenna types and options that will meet yourengineering and user requirements while remaining within budget constraints.We strongly recommend the use of an experienced antenna provider in order torealize the highest gain possible. A well-designed antenna solution willmaximize efficiency, coverage area, and battery life.Selecting an antennaAntenna manufacturers have designed and manufactured a wide variety ofantennas for use on the Mobitex network, and for other RF systems operating inthe 900 MHz range. RIM does not recommend specific antennas because thechoice of antenna is application dependent.The performance of an antenna depends on its configuration and environment:the same antenna will behave differently in one device than in another device,even if both devices use the same RIM 902M radio modem. For example,magmount antennas include a magnetic base that allows the antenna to clamponto a metal surface. This surface is called a ground plane, and reflectselectromagnetic radiation that would otherwise be lost to the antenna. Thiseffectively doubling the length of the antenna by creating a virtual “mirrorimage” of the antenna beneath the plane.
46 Antenna selection: Introduction to antenna terminologyIntegrator’s Guide – RIM 902M OEM Radio ModemAntenna requirementsThe following are the minimum requirements of the antenna system used withthe RIM 902M.Impedance: 50 ΩCenter frequency: 913.5 MHz, ±5 MHz (λ=32.8 cm, ±0.2 cm)this is deliberately biased toward transmit in order tohelp balance the two-way link between the radiomodem and the network base stationFrequencies of operation: 896 to 902M MHz (transmit)935 to 941 MHz (receive)Acceptable return loss: VSWR < 2.0 or RL < −10 dB (minimum)VSWR < 1.5 or RL < −14 dB (recommended)required across all frequencies of operationIntroduction to antenna terminologyThis section introduces some of the terminology that is used to describeantennas, and expands on the summary of antenna requirements, above.Gain and ERPAntennas produce gain by concentrating radiated energy in certain areas, andradiating less energy in other directions. The amount of gain depends on theradiation pattern, antenna match, and antenna efficiency. Antenna gain is givenas a rating of the maximum increase in radiated field energy density relative to adipole antenna expressed in decibels (dBd) of power gain.A dipole is a balanced antenna consisting of two radiators that are each aquarter-wavelength, making a total of a half-wavelength. The widespread use ofhalf-wave dipole antennas at VHF and UHF has led to the use of a half-wavedipole as the reference element.
Interfacing and Controlling the RIM 902MAntenna selection: Introduction to antennaterminology 47RIM 902M OEM Radio Modem – Integrator’s GuideThe power output of the RIM 902M is 62 mW to 2.0 W at the antenna port, andthe antenna gain (or loss) will result in an increase (or decrease) in this value.The actual output is called the Effective Radiated Power, or ERP. For example,if the RIM 902M is putting out 2.0 W of power to a 2.3 dBd gain antenna, theERP is 2.0 × 10^(2.3÷10) = 3.4 W, the actual power radiated by the antenna inthe direction of maximum gain and polarization.Impedance matching, return loss, and VSWRThe antenna, cables, and connectors in a radio frequency system must all possessthe same impedance. The impedance required by the RIM 902M is 50 Ω, whichis a widely-available industry standard. Any deviation from this value may resultin impedance mismatch.Impedance mismatch can be caused by cable connections, cable lengths, andimperfections in the cables and connectors. The mismatch causes some of theradio frequency energy to be reflected back from the location of the mismatch.This interferes with the signal and reduces its amplitude, resulting in a powerloss.Antenna mismatch can be expressed as a return Loss (RL), which is simply theratio of reflected power to the incident power, expressed in decibels.RL =× 10 10log PPreflectedoutputEquation 1: Return LossThe Voltage Standing Wave Ratio (VSWR) is another way of expressing theratio of incident power (from the RIM 902M) to reflected power (into theRIM 902M).VSWR =+1PP1 - PPreflectedoutputreflectedoutputEquation 2: VSWR
48 Antenna selection: Positioning the antennaIntegrator’s Guide – RIM 902M OEM Radio ModemVSWR = 1 or RL = −∞ dB is a perfect match. In practice, there will always beimperfections, which means that VSWR will be greater than 1 and RL will be anegative number.VSWR and RL normally vary as a function of frequency. The RIM 902M’sfrequency range includes 896 to 902M MHz (transmit) and 935 to 941 MHz(receive). The minimum acceptable match across this range must beVSWR < 2.0 or RL < −10 dB. For best performance, the recommended antennamatch at these frequencies is VSWR < 1.5 or RL < −14 dB.Antenna sizeThe optimal antenna radiation efficiency is produced by an antenna measuringone wavelength, λ. The value of λ for the RIM 902M is 32.8 cm, and iscalculated by dividing the speed of light c = 3 x 108 m/s by the center frequencyf = 913.5 MHz. Because the RIM 902M’s receiver is so sensitive, this valueincludes a 5 MHz bias toward the transmit frequencies to help balance the uplinkand downlink between the radio modem and the network base station.Antenna lengths of λ/2, λ/4, and λ/8 also work well, and usually result in arelatively well matched antenna. λ/2 or λ/4 can be electrically “shortened” byadding load matching elements to control the antenna match. However, thisshortening will reduce the antenna efficiency and therefore the effective radiatedpower.Positioning the antennaProper positioning of the antenna will maximize the gain provided by theantenna. In determining the proper position, the designer must carefully considerthe environment in which the device will be used. Physical devices can varysignificantly, and incorporating the antenna is an integral part of a successfuldesign.The Mobitex network is based on vertically polarized radio-frequencytransmission. Therefore, the antenna should ideally be oriented so that itprovides vertical polarization. This is achieved by positioning the antennavertically upward when the RIM 902M is in use. In small, hand-held devices, it
Interfacing and Controlling the RIM 902MAntenna selection: Shielding 49RIM 902M OEM Radio Modem – Integrator’s Guidemay be convenient to design the unit in such a way that the antenna folds out ofthe way when not in use.The antenna should be located as far from the active electronics of thecomputing device as possible. In general, metal construction in the case of thecomputing device and its internal components may attenuate the signal in certaindirections. This is not desirable, as it would reduce the sensitivity and transmitperformance of the radio modem when the computing device is held orpositioned in certain orientations. However, the judicious use of metal in theconstruction of a ground plane for an antenna can significantly improve theantenna gain and the coverage area of the system.If the computing device is designed to sit on a surface, then the antenna shouldbe as far from the bottom of the device as possible. This will reduce RFreflections whenever the device is placed on a metal surface.When the computing device is hand-held or is worn next to the body of the user,the antenna should be positioned to radiate away from the body. Otherwise, thebody will absorb the radiated energy and the effective coverage area of the radiowill be reduced.For best results, the antenna should be connected directly to the antenna cable. Ifan extension cable is required, it should be low loss, as short as possible, andhave an impedance of 50 Ω. It is important that a proper matching connector beused, as each connector in the signal path introduces a return loss and reducesperformance.ShieldingThe electrical design of the RIM 902M provides high immunity to RF noise. Themetal casing also acts as a shield to help minimize the effect of RF interferenceoriginating from the computing device to which it is attached, and to prevent theRIM 902M from emitting RF energy into the computing device and disruptingthe computing device’s operation.Consequently, you do not need to provide any additional RF shielding betweenthe RIM 902M and a computing device. In fact, it would be more important forthe power supply to the RIM 902M to be free of high-frequency electrical noise,than to provide additional RF shielding.!
50 Antenna selection: ShieldingIntegrator’s Guide – RIM 902M OEM Radio ModemThe antenna must be positioned in such a way that the radiated energy is directedaway from the computing device. If this is not possible, then RF shielding maybe required between the antenna and the computing device.Note that circuits with a high impedance, and sensitive analog circuits, areespecially vulnerable to nearby radio frequency emissions, and may need to beshielded. Typically affected circuits include CRTs and LCD display drivers.
SpecificationsThe following is a summary of the RIM 902M OEM radio modemspecifications.Power supply & typical current usage• Single power supply; operating range: 4.1 to 4.75V DC• Single 3.0V logic line to turn on/off• Typical off current consumption: less than 10µA• Battery save stand-by mode: 0.2 mA (at 4.5V)• Receive / express stand-by mode: 57 mA (at 4.5V)• Transmit mode: up to 1.7A (at 4.5V, output 2.0W)• Average current usage: 20 mA (at 4.5V, based upon 94% standby, 5% receive, 1%transmit)RF properties• Transmit frequency: 896 to 902M MHz• 2.0 W nominal maximum transmit power at antenna port• Transmitter can reduce output power to 0.06 Watts (-15 dB) when it is close to thebase station, to balance radio link• Receive frequency: 935 to 941 MHz• Receive sensitivity: -118 dBm at 0.01 bit error rate (BER)• 8000 bps 0.3 BT GMSK• FCC Parts 15 & 90• Industry Canada RSS 122Serial communications• 3.0V asynchronous serial port• 7 bit with parity (MASC) or 8 with no parity (RAP)• Link speed: 9600 bps• Link level protocols:♦ Radio Access Protocol (RAP)♦ Mobitex Asynchronous Communication (MASC)
52 Specifications: ShieldingIntegrator’s Guide – RIM 902M OEM Radio ModemOther features• A simple-to-use firmware utility displays serial number, MAN, RSSI level, batterystrength, and network parameters. It can also select different Mobitex networks or"ping" the network to test the radio modem.• Software can activate radio• Hardware flow control• Radio parameters stored at power down• Terminal devices may power-down while radio-modem remains operational• Certified by RAM Mobile Data to meet Mobitex Interface Specifications (MIS)including the following features:♦ Personal subscriptions♦ ESN verification♦ Switching between different Mobitex networks♦ Frame and continuous modesMechanical & environmental properties• Weight: 1.2 oz (35 g), including case• Footprint: 42 by 69.5 mm• Thickness: 8.4 mm• 3.0V serial connector: 22 pin FPC (Flexible Printed Circuit) connector• Antenna cable connector: MMCX• Tested to IEC 68-2-6 Part 2 for vibration• Metal case, available in a variety of materials• Operating temperature tested to: -30°C to +70°C (at 5-95% relative humidity, non-condensing)• Storage temperature: -40°C to +85°C
Glossary of termsTerm: Meaning:c The speed of light.dB decibel. A measure of power, based on a logarithmic scale.Embedded System A computer without the normal display, keyboard, and diskdrives of a PC.FPC Flexible Printed Circuit. The serial communication cableon the RIM 902M is made using this type of flat multi-conductor wiring.Gain In this document, refers to increase/decrease in radiatedpower.MAN Mobitex Access Number. Each Mobitex radio modem hasone unique MAN. A MAN is a 24-bit number. The networkoperator will assign a MAN to each radio modem whenthey authorize its use on their Mobitex network.MASC Mobitex Asynchronous Serial Communications. The linklayer protocol exchanged via an asynchronous full-duplexserial channel between a data terminal or computing deviceand the RIM 902M OEM Radio Modem.MMCX The connector on the RIM 902M to which an antenna cableis connected.Mobitex A radio network and its communication protocols, createdby Ericsson and the Swedish TelecommunicationsAdministration.MPAK Mobitex Data Packet. A parcel of data transferred betweenthe Mobitex network and the radio modem.Network Operator The corporation or agency which installs, maintains andauthorises use of a Mobitex network in a given area,usually within one country.Noise Refers to undesired, random interference combining withthe signal. If the device is not immune to noise, theinterference must be overcome with a stronger signalstrength. Noise can be produced by electronic components.
54 Glossary of terms: ShieldingIntegrator’s Guide – RIM 902M OEM Radio ModemTerm: Meaning:OEM Original Equipment Manufacturer. Usually implies that the“OEM product” is re-labelled with another manufacturer’sname. The RIM 902M is designed to be embedded in OEMterminals, PCs and data gathering equipment, and as suchthe equipment it is embedded in will not normally carryRIM’s name.OSI The Open Systems Interconnection model allows differentsystems, following the applicable standards, tocommunicate openly with each another.Polarity Direction of current flow. Connecting some cables with thewrong polarity (i.e. backward) may damage the device.Radio Modem A device which provides modulation and demodulation fora radio frequency communications system.Radiation In this document, “radiation” refers to the emission ofelectromagnetic energy in the radio frequency (RF) band.Do not confuse this with radioactive particle emissionscaused by nuclear reactions.RAP Radio Access Protocol. An alternative to the MASCprotocol, found on the RIM 902M. Provides simplerimplementation and faster, reliable operation.Return Loss A measure of antenna matching.RF Radio Frequency.RS-232 The standard asynchronous serial communications interfaceused by most existing personal computers and mini-computers. Usually refers to both the communicationsprotocol and the electrical interface.SMA An RF connector type.TTL Transistor-Transistor Logic. Used in digital circuits. Low(0) is represented by ~0 V and High (1) is ~5 V.Type Approvals These approvals are required by most governments beforeradio transmitters and equipment containing radiotransmitters can be used. In the USA, a device must betested and certified by an independent lab which isrecognized by the FCC.UART Universal Asynchronous Receiver/Transmitter. Used as aninterface between a microprocessor and a serial port.VSWR Voltage Standing Wave Ratio. A measure of antennamatching. See Chapter 5, Antenna Integration.
IndexAAntennaefficiency • 48gain • 46gain, maximizing • 48physical location • 49return loss • 47, 54shielding • 49SMA connector • 54VSWR • 47, 54CCablesserial • 27, 53EEmbedded system • 53IIndustry Canada Certification • iiInterfaceabout • 35connecting to • 27connecting to an RS232 device • 43pin descriptions • 37UART • 54Interface and Test BoardLED indicators • 11MMAN • 53MASC • 53MOA • 4Mobitex • 53overview • 4packet switching • 5Mountingpermanent • 26requirements • 24MPAKs • 5NNoiseFCC compliance statement • i, iinoise immunity • 2shielding • 49OOEM • 54PPower supplyabout • 31alkaline batteries • 33automotive supplies • 34load specifications • 31plug-in supply • 34rechargeable batteries • 32RReliabilitynoise immunity • 2RIM 900battery life • 3
56 Index: ShieldingIntegrator’s Guide – RIM 902M OEM Radio Modemcontrolling • 43features • 1output power • 2physical size • 3, 22RS232 • 54SSchematics8250 serial interface • 44Shutdown • 42Startupturning the radio on • 42TURNON • 38TTemperature range • 22

Navigation menu