Integrator’s Guide RIM 902M OEM Radio Modem
RIM 902M OEM Radio Modem Integrator’s Guide Last Updated: January 11, 1999 Model No. R902M-2-O © 1999, RESEARCH IN MOTION LIMITED Research 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.
FCC Compliance Statement (USA) FCC Class B Part 15 This device complies with Part 15 of FCC Rules. Operation is subject to the following two conditions: 1. This device may not cause harmful interference, and 2. This device must accept any interference received, including interference that may cause undesired operation. Warning Changes or modifications to this unit not expressly approved by the party responsible for compliance could void the user’s authority to operate this equipment.
Industry Canada Certification This device complies with Industry Canada RSS 119, under certification number TBD. IC Class B compliance This device complies with the Class B limits for radio noise emissions as set out in the interference-causing equipment standard entitled “Digital Apparatus,” ICES-003 of Industry Canada.
Contents FCC Compliance Statement (USA) .......................................... i Industry Canada Certification ................................................. ii About this guide....................................................................... v 1. Introduction ................................................................. 1 Radio performance ......................................................................... 1 Mobitex network technology ................................................
Introduction to antenna terminology............................................. 46 Positioning the antenna................................................................. 48 Shielding....................................................................................... 49 Specifications ......................................................................... 51 Glossary of terms................................................................... 53 Index .................................................
About this guide This document is a guide to integrating the RIM 902M OEM radio modem into a variety of devices such as laptop computers, handhelds, vending machines, point-of-sale terminals, vehicle-based mobile terminals, and alarm system.
1 1. Introduction With the introduction of the RIM 902M, Research In Motion (RIM) has set a new standard for radio modem performance. The RIM 902M is unrivalled in the key areas of receiver sensitivity, output efficiency, noise immunity, and power consumption. Its small size and weight make it suitable for virtually any wireless data application, including handheld devices and mobile terminals.
2 Introduction – Radio performance Receiver sensitivity Receiver sensitivity is a measure of how well a radio modem can “hear” a network base station. This figure is important when a device will be used in areas where signal strength is weak, such as inside buildings and in locations that are not close to a base station. A radio modem with good receiver sensitivity can be used in more places than a radio modem with poor sensitivity. The RIM 902M has a receiver sensitivity of –118 dBm, or 0.0016 picowatts.
Introduction – Radio performance 3 Low power requirements If you are planning to integrate the RIM 902M into a handheld or portable device, battery life is a critical issue: your customers will insist on long lasting devices without heavy battery packs. The RIM 902M sets a new power consumption standard for Mobitex radio modems. This ensures efficiency and maximizes battery life. Transmitting data: 1.7 amps or less (at 4.
4 Introduction – Mobitex network technology Mobitex network technology The Mobitex wireless network technology, developed by Eritel in 1984 for Swedish Telecom, has become an international data communication standard. Now managed by the Mobitex Operators Association (MOA), which controls the specifications for this open standard, Mobitex is a secure, reliable, wireless packet switching network specifically designed for wide-area wireless data communications. Mobitex networks are deployed around the world.
Introduction – FCC radio frequency exposure rules 5 forwards it to the mobile. This prevents data loss, and increases the reliability of transmission. Mobitex is optimized for data communication. It uses a packet switching technique to provide the greatest flexibility in data transmission.
6 Introduction – FCC radio frequency exposure rules RF 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 end products such as hand-held and body-worn devices to comply with FCC RF radiation requirements with respect to SAR limit.
Introduction – FCC radio frequency exposure rules 7 wrists, feet and ankles. The 1.6 W/kg limit applies for most of RIM OEM integrators. The limit for MPE is 0.6 mW/cm2 at 900 MHz. Guidelines RF exposure distance is based on normal operating proximity to the user’s or nearby persons’ bodies. This distance is measured from any part of a radiating structure, which is generally the antenna to the closest body part.
Compliance with respect to SAR limits which satisfy MPE limits, would not require warning labels, however, an RF radiation warning label can be used to alert the user or nearby persons about abnormal usage conditions. Warning to Integrators and Users To meet the FCC RF exposure requirement for mobile transmitter end products using the Larsen NMO 3E 900B, 3 dBd antenna, ensure that the antenna is at least 23 cm away from the user or nearby persons when transmitting.
10 Getting started – Test board overview e-mail: rim902m@rim.net phone: +1 (519) 888-7465 fax: +1 (519) 888-7884 web: www.rim.net Test board overview The RIM test board provides a standard RS-232 serial interface between a PC and the radio modem. It is designed to help you quickly interface the RIM 902M to a standard PC (through a COM port) or a terminal device with an RS-232 serial port.
Getting started – How to connect the test board 11 On/off switch With the switch in the ON position, the radio will turn on whenever power is applied to the test board. When the switch is moved to the OFF position, the radio will shut down. Power supply The RIM 902M must be provided with a clean, high-current power source. In this case, we use a standard plug-pack to provide the current necessary to operate the radio.
12 Getting started – How to connect the test board 1. Flat serial cable (test board to radio) The flat serial interface cable carries data between the test board and the RIM 902M. Control and status signals such as TURNON are also carried on this cable. Use this cable to connect the RIM 902M’s serial connector to the test board. This cable also carries clean, regulated power to the RIM 902M.
Getting started – The MENU diagnostics tool 13 5. Turn the system on The power switch on the test board is connected to the TURNON line of the RIM 902M radio modem. To determine whether the radio is on, look at the LED marked ONI. It is lit when the radio is on. The MENU diagnostics tool Now that you have successfully connected your RIM 902M radio modem to your PC, you are ready to send a test packet through the Mobitex network.
14 Getting started – The MENU diagnostics tool Type 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 reenter menu until the radio modem responds. The word “menu” itself will probably 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 and connected to the PC, and that all cables are securely connected.
Getting started – The MENU diagnostics tool 15 The Battery indicator shows the level of supplied voltage. The battery level is updated once every thirty seconds, or whenever you press D. Network tells you which network you are currently using. The example shows RMDUS (BellSouth Wireless Data, formerly RAM Mobile Data, operates a Mobitex network in the United States) and CANTEL (Cantel AT&T operates a Mobitex network in Canada).
16 Getting started – The MENU diagnostics tool geographic area often share an Area address. Contact your network operator if you want to know the location of network base stations. Status describes the current state of the radio. Other documentation may also refer to the Status value as the radio’s internal fault bits. The following table shows the interpretation of the Status bits.
Getting started – The MENU diagnostics tool 17 How to change to a different network The RIM 902M radio may be used on different Mobitex networks operating on different channels in the 900 MHz range. Up to 16 network channel lists may be programmed by RIM into each radio. If the network shown is not the correct one, you can choose another from the list of networks available. Press N and the MENU utility will present an additional prompt for selecting the network, as shown below.
18 Getting started – The MENU diagnostics tool RIM 902M Firmware Version 1.0.0 (c) 1999 Research In Motion Limited Radio Setup Radio Serial Number = 031/11/066300 Command Key ----------Q Description ----------Quit and reset the radio. N P Set the current network. Ping: Send a Status MPAK to yourself. Networks Available: ------------------1. RMDUS (B433/B433) 2.
Getting started – The MENU diagnostics tool 19 RIM 902M Firmware Version 1.0.0 (c) 1999 Research In Motion Limited Radio Setup Radio Serial Number = 031/11/066383 Command Key ----------Q Description ----------Quit and reset the radio. N P Set the current network. Ping: Send a Status MPAK to yourself. Networks Available: ------------------1. RMDUS (B433/B433) 2.
3 3. Mechanical integration This chapter provides information about the RIM 902M that will be useful in determining the physical positioning of the radio modem within an application. Environmental properties and testing, physical properties, mounting methods, and connector information are presented. Environmental properties During environmental testing, RIM takes samples of its radio modems and subjects them to a variety of harsh conditions.
22 Mechanical integration: Physical properties Storage temperature The RIM 902M OEM radio modem may be stored at a temperature from -40°C to +85°C (-40°F to +185°F). Operating temperature The 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 occur past this point, especially when packets are transmitted frequently.
Mechanical integration: Physical properties 23 RIM 902M OEM Radio Modem – Integrator’s Guide
24 Mechanical integration: Mounting methods Mounting methods The RIM 902M OEM radio modem may be securely fastened using a variety of methods. The operating environment must be carefully considered when choosing a mounting option. For example, extreme temperature or heavy vibration may require a special mounting solution. It is important to ensure that the RIM 902M remains securely attached in the environment where it will be used.
Mechanical integration: Mounting methods 25 Tie wraps Tie wraps can be used to as a secure but non-permanent means of attaching the RIM 902M to a surface.
26 Mechanical integration: Mounting methods into the surface on either side of the RIM 902M. This allows the radio to be attached 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 the radio case while tightening the tie wraps pushes down on the edge of the radio case.
Mechanical integration: Cables and connectors 27 Cables and connectors There are two connectors on the RIM 902M radio modem. These connectors allow interfacing from the radio modem to a serial computing device, a power supply, and an antenna. Serial cable and connector The RIM 902M serial communication and control signals are carried on a flat 22-conductor 0.30 mm (0.012”) thick flexible printed circuit (FPC) cable in 1.00 mm centerline spacing, which can plug into a matching connector.
28 Mechanical integration: Cables and connectors This cable can plug into a matching 22-position 1.0 [0.039] horizontal FPC connector. A variety of connectors are manufactured by Molex. More information about each connector, including mechanical drawings, is available from the manufacturer’s web site (www.molex.com), or you can contact RIM (rim902m@rim.net) for help with selecting an appropriate connector for your application.
Mechanical integration: Cables and connectors 11MMCX-50-2-1C/111 16MMCX-50-2-1C/111 25SMA-50-2-25/111 EZ Flex 405 133REEZ4-12-S2/1216 133REEZ4-12-S2/1699 29 Straight MMCX connector Right-angle MMCX connector SMA connector Low-loss matching (50 Ω) cable 8” cable, straight MMCX to SMA 8” cable, right-angle MMCX to SMA The following cable is included with the RIM 902M Developer’s Kit: Contact: Huber & Suhner Essex Junction, VT, USA tel: (802) 878-0555 fax: (802) 878-9880 www.hubersuhnerinc.
3 4. Power requirements The RIM 902M radio modem must be provided with a clean power source capable of delivering bursts of high current. This can be provided by a plug-in power supply unit, a rechargeable battery pack, or single use batteries. RIM has conducted extensive research and has developed guidelines for integrators to follow when designing the power supply system for the RIM 902M.
32 Power requirements: Batteries Radio load profile (at 4.5V) Transmitter ON at 2.00 W to antenna worst-case peak instantaneous (due to extreme temperature, poorly matched antenna, etc.) 1.7 A 2.2 A Receiver ON In EXPRESS mode, the receiver is always ON. In POWERSAVE mode, the receiver is typically ON for 0.15 s then OFF for 9.85 s 57 mA Standby (transmitter and receiver are both OFF) Standby mode occurs for 9.85 s out of 10 s if in POWERSAVE mode and no activity has taken place for previous 10 s 0.
Power requirements: Batteries 33 team can help you determine whether a particular battery is suitable for your application. 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 efficient as another when the radio transmitter is turned on.
34 Power requirements: Plug-in supplies Plug-in supplies A plug-in supply converts normal AC power (usually 110 volts or 220 volts) into a steady DC source that can be used instead of batteries. The plug-in supply must be designed to ensure voltage spikes, lightning, and other power fluctuations cannot damage the radio modem. Transient voltage protection zener diodes, or other spike arrestor circuits, may be added to keep the inputs within the limits given in the RIM 902M load specifications.
4 5. Interface specification The asynchronous serial interface on the RIM 902M operates at 3.0V. It is similar 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 a UART to a microprocessor data bus.
36 Interface specification: MASC and RAP link-layer protocols designed to be extremely robust and redundant, and should be used when the serial 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 links are short enough to make bit errors extremely unlikely. This is especially true for smaller devices such as laptops and PDAs.
Interface specification: Pin descriptions 37 influence on the speed or reliability of communication between the radio and the Mobitex network. The RIM engineering development team (e-mail: rim900@rim.net) can help you select the protocol most suited to your needs. Pin descriptions All input and output lines are 3.0 volt logic; however, they will also be able to drive 3.3 volt systems. Further, all input lines to the serial port are 5.0 volt tolerant and outputs will be capable of driving 5.
38 Pin 6 Interface specification: Pin descriptions ~COV ~Coverage This is an output from the radio. The active state of this line is low, and indicates that the radio is in network coverage, 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 Ground This line should be tied to the system ground of the host unit to ensure proper operation.
Interface specification: Pin descriptions 39 This output from the radio that is asserted while the RIM 900 is transmitting a packet to the network base station. TRI can be used to provide real-time visual feedback 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 Indicate This is an output from the radio.
40 Interface specification: Pin descriptions device to the RIM 900 may be lost. This is a flow control mechanism that is normally 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 modem with an impedance of at least 20 kΩ. Pin 16 ~RTS ~Request To Send This line is an input to the radio. Its active (request to send) state of this line is low. All MASC implementations require this line.
Interface specification: Pin descriptions Pin 19 ~DTR 41 ~Data Terminal Ready This line is an input to the radio. The active (data terminal ready) state of this line is low, and indicates that the computing device is ready to receive data from the RIM 900. De-asserting this line high will turn communication off; the RIM 900 would not attempt to deliver data to the computing device until ~DTR is again asserted low.
42 Interface specification: How to turn the radio on and off Pin 21 RX Receive This 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 be connected to the host terminal’s Receive Data input. This line carries data at 9600 bits per second. MASC parameters are 7 bits, Even parity, 1 stop bit. RAP parameters are 8 bits, No parity, 1 stop bit.
Interface specification: Interface to an RS-232 device 43 Shutdown will normally require several seconds to complete, and the radio should not be disturbed while it is shutting down. Attempting to communicate with the radio during shutdown may extend the time taken to perform shutdown operations. The ONI signal will be de-asserted (low) when the radio has shut down. All serial inputs to the radio should be low when the radio is turned off.
44 Interface specification: Interface to microprocessor Integrator’s Guide – RIM 902M OEM Radio Modem
5 6. Antenna selection The antenna is one of the most important components of a wireless communication system. The right antenna will maximize the coverage area of the RIM 902M. The antenna that you choose should complement the needs of your specific project. There are many different antenna types and options that will meet your engineering and user requirements while remaining within budget constraints.
46 Antenna selection: Introduction to antenna terminology Antenna requirements The following are the minimum requirements of the antenna system used with the RIM 902M. Impedance: 50 Ω Center frequency: 913.5 MHz, ±5 MHz (λ=32.8 cm, ±0.2 cm) this is deliberately biased toward transmit in order to help balance the two-way link between the radio modem and the network base station Frequencies of operation: 896 to 902M MHz (transmit) 935 to 941 MHz (receive) Acceptable return loss: VSWR < 2.
Interfacing and Controlling the RIM 902MAntenna selection: Introduction to antenna terminology 47 The power output of the RIM 902M is 62 mW to 2.0 W at the antenna port, and the 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, the ERP is 2.0 × 10^(2.3÷10) = 3.
48 Antenna selection: Positioning the antenna VSWR = 1 or RL = −∞ dB is a perfect match. In practice, there will always be imperfections, which means that VSWR will be greater than 1 and RL will be a negative number. VSWR and RL normally vary as a function of frequency. The RIM 902M’s frequency range includes 896 to 902M MHz (transmit) and 935 to 941 MHz (receive). The minimum acceptable match across this range must be VSWR < 2.0 or RL < −10 dB.
Interfacing and Controlling the RIM 902MAntenna selection: Shielding 49 may be convenient to design the unit in such a way that the antenna folds out of the way when not in use. The antenna should be located as far from the active electronics of the computing device as possible. In general, metal construction in the case of the computing device and its internal components may attenuate the signal in certain directions.
50 Antenna selection: Shielding The antenna must be positioned in such a way that the radiated energy is directed away from the computing device. If this is not possible, then RF shielding may be required between the antenna and the computing device. Note that circuits with a high impedance, and sensitive analog circuits, are especially vulnerable to nearby radio frequency emissions, and may need to be shielded. Typically affected circuits include CRTs and LCD display drivers.
Specifications The following is a summary of the RIM 902M OEM radio modem specifications. 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.
52 Specifications: Shielding Other features • A simple-to-use firmware utility displays serial number, MAN, RSSI level, battery strength, and network parameters. It can also select different Mobitex networks or "ping" the network to test the radio modem.
Glossary of terms Term: 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 disk drives of a PC. FPC Flexible Printed Circuit. The serial communication cable on the RIM 902M is made using this type of flat multiconductor wiring. Gain In this document, refers to increase/decrease in radiated power. MAN Mobitex Access Number. Each Mobitex radio modem has one unique MAN.
54 Glossary of terms: Shielding Term: Meaning: OEM Original Equipment Manufacturer. Usually implies that the “OEM product” is re-labelled with another manufacturer’s name. The RIM 902M is designed to be embedded in OEM terminals, PCs and data gathering equipment, and as such the equipment it is embedded in will not normally carry RIM’s name. OSI The Open Systems Interconnection model allows different systems, following the applicable standards, to communicate openly with each another.
Index A Antenna efficiency • 48 gain • 46 gain, maximizing • 48 physical location • 49 return loss • 47, 54 shielding • 49 SMA connector • 54 VSWR • 47, 54 C Cables serial • 27, 53 MASC • 53 MOA • 4 Mobitex • 53 overview • 4 packet switching • 5 Mounting permanent • 26 requirements • 24 MPAKs • 5 N Noise FCC compliance statement • i, ii noise immunity • 2 shielding • 49 O E OEM • 54 Embedded system • 53 P I Industry Canada Certification • ii Interface about • 35 connecting to • 27 connecting to an RS
56 Index: Shielding controlling • 43 features • 1 output power • 2 physical size • 3, 22 RS232 • 54 S Schematics Integrator’s Guide – RIM 902M OEM Radio Modem 8250 serial interface • 44 Shutdown • 42 Startup turning the radio on • 42 TURNON • 38 T Temperature range • 22
