Laird Connectivity LX2400 LX2400-3, LX2400-10 and LX2400-150 User Manual exb22

AeroComm Corporation LX2400-3, LX2400-10 and LX2400-150 exb22

Revised manual please remove the other

LX2400S TransceiverPRELIMINARYSpecifications Subject to ChangeHardware and SoftwareInterface SpecificationVersion 3.313256 W. 98th StreetLenexa, KS 66215(800) 492-2320Fax (913) 492-1243www.aerocomm.comwireless@aerocomm.com§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§§
Copyright Information/FCC User’s NoticeCopyright Copyright © 2000 AEROCOMM, Inc. All rights reserved.Information The information contained in this manual and the accompanyingsoftware programs are copyrighted and all rights are reserved byAEROCOMM, Inc. AEROCOMM, Inc. reserves the right to makeperiodic modifications of this product without obligation to notifyany person or entity of such revision. Copying, duplicating, selling,or otherwise distributing any part of this product without the priorconsent of an authorized representative of AEROCOMM, Inc. isprohibited.All brands and product names in this publication are registeredtrademarks or trademarks of their respective holders.AGENCY APPROVAL OVERVIEWUS/FCC CAN/IC EUR/EN** Portable Mobile FixedLX2400-3 XXXXXXLX2400-10 XXXXXXLX2400-150 X X X-30cm X-30cm** Does not include France and SpainNote: The product approvals above are with antennas specified below.FCC NOTICELABELING REQUIREMENTS WARNING: This device complies with Part 15 of the FCC Rules. Operation is subject to the following twoconditions: (1) this device may not cause harmful interference and (2) this device must accept anyinterference received, including interference that may cause undesired operation. WARNING: The Original Equipment Manufacturer (OEM) must ensure that FCC labeling requirements aremet. This includes a clearly visible label on the outside of the OEM enclosure specifying“Contains Transmitter Module FCC ID: KQL-LX2400”, as well as the FCC Notice above.
ANTENNA WARNINGAPPROVED ANTENNA LISTManufacturer Part Number Type Gain Application*LX2400-3LX2400-10LX2400-150Centurion WCP-2400-MMCX ¼ Wave Dipole 2dBi P/M/F X XMaxrad Z986 Patch 2.5dBi FXAeroComm NZH2400-MMCX (External) Microstrip 1dBi PX XAeroComm NZH2400-I (Integrated) Microstrip 1dBi PXNearson S131CL-5-RMM-2450S ¼ Wave Dipole 2dBi P/M/F X XNearson S181FL-5-RMM-2450S ¼ Wave Dipole 2dBi P/M/F X XNearson S191FL-5-RMM-2450S ¾ Wave Dipole 3dBi M/F X X*P=Portable, M=Mobile, F=Fixed/BasestationRF EXPOSURE LX2400-3 AND LX2400-10RF EXPOSURE LX2400-150 WARNING: The LX2400-3 and LX2400-10 have been tested to ensure compliance with FCC SAR exposurelimits. Any alterations to the product including use of antennas other than those specified in thetable above will require the Original Equipment Manufacturer (OEM) to ensure that this product,when integrated, meets FCC SAR exposure limits. WARNING: This device has been tested with an MMCX connector with the antennas listed below. Whenintegrated in the OEMs product, these fixed antennas require installation preventing end-users fromreplacing them with non-approved antennas. Any antenna not in the following table must be testedto comply with FCC Section 15.203 for unique antenna connectors and Section 15.247 foremissions. WARNING: The LX2400-150 is approved only for mobile and base station applications. To satisfy FCC RFexposure requirements for mobile and base station transmitting devices, a separation distance of30cm or more should be maintained between the antenna of this device and persons duringoperation. To ensure compliance, operations at closer than this distance is not recommended.The preceding statement must be included as a CAUTION statement in manualsfor OEM products to alert users on FCC RF Exposure compliance.
RF EXPOSURE OVERVIEWSARSpecificationswith BodyTissue(W/Kg)MinimumRF ExposureDistance(cm)AntennaManufacturer Part Number Type Gain Application*LX2400-3LX2400-10LX2400-150Centurion WCP-2400-MMCX ¼ WaveDipole2dBi P/M/F N/A 0.400 30Maxrad MC2400 Patch 2.5dBi FN/A N/A 30AeroComm NZH2400-MMCX (External) Microstrip 1dBi PN/A 0.308 30AeroComm NZH2400-I (Integrated) Microstrip 1dBi P0.057 N/A N/ANearson S131CL-5-RMM-2450S ¼ WaveDipole2dBi P/M/F N/A 0.265 30Nearson S181FL-5-RMM-2450S ¼ WaveDipole2dBi P/M/F N/A 0.189 30Nearson S191FL-5-RMM-2450S ¾ WaveDipole3dBi M/F N/A 0.118 30*P=Portable, M=Mobile, F=Fixed/Basestation
Revisions DescriptionVersion 1.0 Initial Release Version - 01/20/2000Version 2.0 Not ReleasedVersion 3.0 Release Version - 2/15/2000Full Document Update – major changes:1. The Transmit Sync byte has been changed2. The previous version called out RTS rather than TE for the Transmit Enable pin. This has been correctedVersion 3.1 Release Version - 5/23/20001. Corrected Serial Interface data rate to 57,600bps maximum2. Add specifications on LX2400S-10 and LX2400S-10A3. Add ordering informationVersion 3.2 Release Version - 8/1/20001. Corrected RF data rate to 144,000bps maximum2. Corrected Frequency band to 2.402GHz – 2.478GHz3. Added new column to Table 2. Now shows 3mW & 10mW defaults4. Corrected hop time from 120ms to 100ms5. Added current consumptions specifications for LX2400S-10(A)6. Changed Input Voltage tolerance from 5% to 2%7. Updated Table 2 with new Control Bit definitions8. Updated Section 3.2.6.1.5 to include Control Bit definitions9. Updated FCC section.Version 3.3 Release Version - 9/14/20001. Update approved antenna table and Agency Requirements2. Correct product and developer kit part numbersCopyright © 2000AeroComm, Inc.This material is preliminary.Information furnished by AeroComm in this specification is believed to be accurate. Devices sold byAeroComm are covered by the warranty and patent indemnification provisions appearing in its Terms ofSale only. AeroComm makes no warranty, express, statutory, and implied or by description, regarding theinformation set forth herein. AeroComm reserves the right to change specifications at any time and withoutnotice.AeroComm’s products are intended for use in normal commercial applications. Applications requiringextended temperature range or unusual environmental requirements such as military, medical life-support orlife-sustaining equipment are specifically not recommended without additional testing for such application.
CONTENTS 09/22/00 Preliminary 6TABLE OF CONTENTS1. OVERVIEW .............................................................................................................................................................72. LX2400S SPECIFICATIONS ..............................................................................................................................83. THEORY OF OPERATION..................................................................................................................................93.1 INTERFACE SIGNAL DEFINITION..................................................................................................................93.2 HOST SOFTWARE/HARDWARE INTERFACE DEFINITION.......................................................................103.2.1 Host Transmit Frame Format...........................................................................................................103.2.2 Host Receive Frame Format..............................................................................................................103.2.3 Hopping Status....................................................................................................................................103.2.4 In Range................................................................................................................................................113.2.5 RSSI.......................................................................................................................................................113.2.6 LX2400S Configuration Parameters and Commands..................................................................123.2.7 Data Rates............................................................................................................................................154. INTERFACING TO THE LX2400S...................................................................................................................184.1 OPERATING MODES ...................................................................................................................................184.1.1 RECEIVE MODE.................................................................................................................................184.1.2 TRANSMIT MODE ..............................................................................................................................184.1.3 CONFIGURATION MODE.................................................................................................................194.1.4 HOPPING MODE................................................................................................................................194.1.5 BEACON MODE..................................................................................................................................194.2 LX2400S GLOBAL TIMING PARAMETERS.................................................................................................204.3 LX2400S TRANSMIT MODE TIMING..........................................................................................................204.4 LX2400S CONFIGUATION MODE TIMING.................................................................................................214.5 LX2400S HOPPING AND BEACON TIMING.................................................................................................215. MECHANICAL OVERVIEW ..............................................................................................................................235.1 TRANSCEIVER.................................................................................................................................................235.2 ANTENNA.......................................................................................................................................................236. ORDERING INFORMATION.............................................................................................................................246.1 PRODUCT PART NUMBERS...........................................................................................................................246.2 DEVELOPER KIT PART NUMBERS..............................................................................................................24TABLESTable 1 – Connector J1 Pin Definitions......................................................................................................................9Table 2 – Configuration Parameters.........................................................................................................................12Table 3 – Baud Rate/Timeout......................................................................................................................................13Table 4 – Global Timing Parameters.........................................................................................................................20Table 5 – Transmit Mode Timing...............................................................................................................................20Table 6 – Configuration Mode Timing ......................................................................................................................21Table 7 – Hopping and Beacon Timing......................................................................................................................22
OVERVIEW 09/22/00 Preliminary 7LX2400S FEATURES• Simple 5V TTL level serial interface for fast integration• Integrated Antenna saves space and reduces cost• Frequency Hopping Spread Spectrum for security and interferencerejection• Cost Efficient for high volume applications• Low power consumption for battery powered implementations• Small size for portable and enclosed applications1. OverviewThe LX2400S is a member of AeroComm’s ConnexRF OEM transceiver family. It is designed forintegration into OEM systems operating under FCC part 15.247 regulations for the 2.4 GHz ISM band.The LX2400S is a cost-effective, high performance 2.4 GHz frequency hopping spread spectrumtransceiver. It provides an asynchronous TTL level serial interface for OEM Host communications.Communications include both system and configuration data. The Host supplies system data fortransmission to other Host(s). Configuration data is stored in an on-board EEPROM. All frequencyhopping, synchronization, and RF system data transmission/reception is performed by the LX2400S. Anon-board antenna is integrated into the transceiver in the LX2400S-3. This antenna has coverage and gainsimilar to a dipole antenna.LX2400S operate in a Point-to-Point or Point-to-Multipoint, Client/Server architecture. Onetransceiver is configured as a Server; there can be one or many Clients. To establish synchronizationbetween radios, the Server emits a beacon, upon detecting the beacon, the Client transceiver informs theClient Host and an RF link is established.There are several data rates the OEM should be aware of:• Serial Interface Data Rate – The LX2400S, when interfaced to an AeroComm RS232 interface boardin the SDK (or one provided by the OEM) can be configured at popular PC serial port baud ratesup to 19,200bps on the LX2400S-3 and 57,600bps on the LX2400S-10 and 115,200bps ont theLX2400S-150.• RF Data Rate – The LX2400S transmits data over the air at a gross rate of 144,000bps.• Effective Data Transmission Rate – The LX2400S is a highly efficient, low-latency transceiver. SeeSection 3.2.7 for more information.This document contains information about the hardware and software interface between anAeroComm LX2400S transceiver and an OEM Host. Information includes the theory of operation,specifications, interface definition, and mechanical drawing. The OEM must provide the Host hardware and software to control the radio. Certain timingconsiderations must be followed. The OEM is responsible for ensuring the final product meets all FCCand/or appropriate regulatory agency requirements before selling any product.
SPECIFICATIONS 09/22/00 Preliminary 82. LX2400S SpecificationsGENERALInterface 20 pin mini-connector, See mechanical drawing.Serial Interface Data Rate (See 3.2.6.1.3 & 3.2.6.1.4) LX2400S-3A, PC Baud rates up to 19,200bpsLX2400S-10, PC Baud rates up to 57,600bpsLX2400S-150, PC Baud rates up to 115,200bpsPower Consumption Transmit/ReceiveLX2400S-3A, 100mA/80mA typicalLX2400S-10, 115mA/115mA typicalLX2400S-150, 400mA/115mA typicalChannels (used to create independent networks) 10Security Host DefinedRADIOFrequency Band 2.402 – 2.478 GHzRadio Type Spread Spectrum Frequency HoppingOutput Power (Conducted, no antenna) LX2400S-3A, 2.5mW typicalLX2400S-10, 11.0mW typicalLX2400S-150, 147.9mW typicalEffective Radiated Isotropic Power (EIRP withHighest Gain Antenna)LX2400S-3A, 3.1mW typicalLX2400S-10, 25.1mW typicalLX2400S-150, 288.4mW typicalVoltage 5V nominal +2%, + 50mV rippleSensitivity -90dBm typicalRF Data Rate 144KbpsRange LX2400S-3A, Indoors to 100 ft., Outdoors to 500 ft.LX2400S-10, Indoors to 300 ft., Outdoors to 3000 ft.LX2400S-150, Indoors to 500 ft., Outdoors to 5000 ft.PLL Lock Time 500 us typicalENVIRONMENTALTemperature (Operating) 0 °C to +70 °CTemperature (Storage) -50 °C to +85 °CHumidity (non-condensing) 10% to 90%PHYSICALDimensions 1.65” x 2.65” x 0.20”Antenna LX2400S-3A, Integrated dipoleLX2400S-10, MMCX JackLX2400S-150, MMCX JackWeight Less than 0.5 ounce
THEORY OF OPERATION 09/22/00 Preliminary 93. Theory of Operation3.1 Interface Signal DefinitionThe LX2400S has a simple interface that allows OEM Host communications with the transceiver. Table 1shows the connector pin numbers and associated functions. The I/O direction is also shown. The directionis with regard to the transceiver. All I/O is 5Vdc TTL level signals except for RSSI. All outputs are weaklypulled high (20k – 50k ohms) when left unconnected and are driven high at reset.Table 1 – Connector J1 Pin DefinitionsPin TYPE Signal Name Function1ODCD Not Implemented2OTXD Transmitted data out of the transceiver3IRXD Data input to the transceiver4IDTR Not Implemented5GND GND Signal Ground6ODSR HOP FRAME/Data Set Ready – Active Low when the transceiver ishopping.7OCTS Clear to Send – Active Low when the transceiver is ready to accept datafor transmission. This is in response to a valid TE signal. A Client will notrespond with CTS if it is not in range of a Server.8IRTS Not Implemented9ORI Not Implemented10 PWR VCC 5V + 2%11 PWR VCC 5V + 2%12 ITST_MODE Test Mode1. When pulled low before applying power the transceiver’s serialinterface is forced to a 9600,8,N, 1 rate.2. When pulled low and the CONFIGURATION START BYTEcommand (See 3.2.6.2.1) is sent to the transceiver, ConfigurationMode is entered to read and write parameters in EEPROM13 ORSSI Received Signal Strength - An analog output giving a relative indication ofreceived signal strength while in RECEIVE MODE.14 IWR_ENA EEPROM Write Enable – When pulled low it allows the Host to write theon-board EEPROM.15 IUP_RESET RESET – Controlled by the LX2400S for power-on reset if leftunconnected. After a Stable power-on (4ms ) A 10us high pulse will resetthe LX2400S.16 GND GND Signal Ground17 ITE Transmit Enable – When pulled low, the transceiver switches to transmitmode and will respond with CTS when data can be transmitted by theHost.18 IRE Radio Enable – When the RADIO_ENABLE_ENABLED control bit is setin EEPROM the transceiver will only allow Host communications/controlwhen this line is pulled low. If the RADIO_ENABLE_ENABLED controlbit is cleared, the transceiver ignores this input.19 OPLL_LOCK Factory Use Only – NC20 OIN_RANGE In Range – Active Low when a Client radio is in range of a Server on thesame channel.I = Input to the transceiverO = Output from the transceiver
THEORY OF OPERATION 09/22/00 Preliminary 103.2 Host Software/Hardware Interface Definition3.2.1 Host Transmit Frame FormatThe LX2400S requires the following format in order to transmit a Host’s data packet over the RF link. Theframe consists of 3 bytes of preamble, 1 sync byte, a 16-bit length, and user data.Byte 0 – 055H – preambleByte 1 – 055H – preambleByte 2 – 055H – preambleByte 3 – 03AH – syncByte 4 – Length High (bits 15-8)Byte 5 – Length Low (bits 7-0)Byte 6 – First byte Host DataByte n – Last byte Host DataLength High/Length Low is a 16-bit length value that represents the length of bytes 6 through n inclusive.Both byte and packet gap times must be followed as specified in Table 4. The maximum transmit time is20ms. The maximum length depends on the Host’s Byte and Byte-Gap timing.3.2.2 Host Receive Frame FormatThe LX2400S transmits received RF data, beginning with the Length Bytes, to the Host following thereception of a valid preamble. The preamble and the sync bytes are not transmitted to the Host.Byte 0 – Length HighByte 1 – Length LowByte 2 - First byte Host DataByte n – Last byte of Host Data3.2.3 Hopping StatusIf the SW_HOP_FRAME_ENABLE bit is set in EEPROM, The LX2400S sends an XOFF character to theHost when it is ready to hop. Following the completion of the hop, the LX2400S sends an XON character toinform the Host that the hop is completed. The Host must parse these bytes and assume if transmitting apacket, the data did not reach the destination(s) and re-transmit the packet.XOFF = 0E2H Transmitted at the start of a frequency hop.XON = 0ACH Transmitted at the completion of a frequency hop.The Host can also detect hopping status by monitoring the DSR pin on the connector. The DSR pin isalways enabled.
THEORY OF OPERATION 09/22/00 Preliminary 113.2.4 In RangeThe IN_RANGE pin at the connector will be driven low when a Client radio is in range of a Server on thesame channel. If the Client cannot hear a LX2400S Server for 10 S, the LX2400S Client drives the IN_RANGEpin high and enters a search mode looking for a LX2400S Server. As soon as it detects a Server, theIN_RANGE pin will be driven low. The LX2400 Server can determine what Clients are in range by theServer’s Host software polling the LX2400S Client’s Host.3.2.5 RSSIReceived Signal Strength Indicator is used by the Host as an indication of instantaneous signal strength atthe receiver. The Host must calibrate RSSI without a signal being presented to the receiver. Figure 1 showsapproximate RSSI performance. The RSSI pin requires the Host to provide a 27kΩ pull-down to ground.Output is 1.20V to 4.50V.3.2.6 Figure 1 - RSSI Voltage vs. Received Signal Strength-100-90-80-70-60-50-40-30-20-1001.2 1.3 1.57 2.3 3.8 4.5Voltage (VDC)Signal at Receiver (dBm)
THEORY OF OPERATION 09/22/00 Preliminary 123.2.6 LX2400S Configuration Parameters and Commands3.2.6.1 Configuration ParametersThe Host can program various parameters. The data is stored in EEPROM and becomes active on the nextpower on reset of the LX2400S. Table 2 gives the locations and functions of the parameters that can be reador written by the Host. Factory default values are also shown.Note: Non-Host parameters are used in the EEPROM. The Host must only write to the locations in Table2. Any other location may cause the radio to malfunction.Table 2 – Configuration ParametersPARAMETER EEPROMADDRESS DEFAULT3mW DEFAULT10mW FUNCTIONTYPE 41H 02H 02H Determines if the transceiver is acting as a Clientor Server. 01H = Server 02H = ClientCHANNEL 40H 00H 00H Programmed channel CHANNEL = 00H to 09HBAUDH 43H 00H 00H The High Byte of the programmed baud rate.BAUDL 42H 1EH 0AHThe Low Byte of the programmed baud rateTIMEOUT 53H FEH FEH Serial Byte Gap Timeout ValueCONTROL 45H 10H 10H Radio Control Byte: Bit 7 - Not used - RESERVED (Always 0) Bit 6 – BEACON_ALWAYS 0 = Server beacons after 2.5 seconds of inactivity 1 = Server sends beacon after every hop Bit 5 - Not used - RESERVED (Always 0) Bit 4 - Not used - RESERVED (Always 1) Bit 3 – DATA_FRAME 0 = Disable packet frame 1 = Enable packet frame Bit 2 - Not used - RESERVED (Always 0) Bit 1 – RADIO_ENABLE_ENABLED 0 = Disable RE 1 = Enable RE Bit 0 – SW_HOP_FRAME_ENABLE 0 = Disable XON/XOFF 1 = Enable XONXOFF3.2.6.1.1 TYPE parameterThe TYPE byte tells the transceiver to operate in Client or Server mode. See Section 4 for more detail on theusage of this parameter.
THEORY OF OPERATION 09/22/00 Preliminary 133.2.6.1.2 CHANNEL parameterThe LX2400S can be programmed to one of ten different channels. Client mode transceivers will receive andtransmit to a Server on the same channel as programmed. Servers will receive and transmit to Clients on thesame channel as programmed. CHANNEL can be programmed with a value ranging from 0 to 9.3.2.6.1.3 BAUDRATE parameterThis two-byte value determines the baud rate used for communicating over the serial interface to theLX2400S. TABLE 3 lists values for some popular baud rates. Baud rates below 1200 are not supported.When programming a baud rate the Host must program the associated TIMEOUT value. This value is notused if the TST_MODE line on the connector is pulled low at reset. The baud rate will be forced to 9600.For Baud Rate values other than shown in Table 3, the following equations can be used:BAUD = (18.432E+06/(32*desired baud rate))BAUDH= High 8 bits of BAUD (base16)BAUDL = Low 8 bits of BAUD (base16)3.2.6.1.4 TIMEOUT parameterThe TIMEOUT value is the amount of time the LX2400S will allow between bytes when receiving serialbytes from the Host and receiving bytes on the RF link. It is equal to between two and four byte times.TIMEOUT can always be less than the value specified or calculated, but, never greater.Table 3 – Baud Rate/TimeoutBAUDRATE BAUDH BAUDL TIMEOUT57600*00H 0AH FDH38400*00H 0FH FCH28800*00H 14H FBH19200 00H 1EH F9H14400 00H 28H F7H9600 00H 3CH F3H4800 00H 78H E7H2400 00H F0H CEH1200 01H E0H 9CH* Not Available with LX2400S-3AFor Timeout values other than shown in Table 3, the following equations can be used:IBT = 10/desired baud rateTIMEOUT = (base16) High 8 bits of [2^16-(24/18.432E+06/IBT)]
THEORY OF OPERATION 09/22/00 Preliminary 143.2.6.1.5 CONTROL parameterThe individual bits in the control byte alter the operation of the LX2400S. The Bit definitions follow:Bit 0 – Controls if the LX2400S sends XON and XOFF characters to the Host, XOFF at the start ofthe HOP and XON at the end of the HOP.Bit 1 – Controls if the LX2400S uses the RE pin on the connector to enable Host communications.Bit 2 – Reserved for future use, always cleared to 0.Bit 3 – Pin 12 transitions low at the start of a packet and high at the completion of a packet.Bit 4 – Reserved for future use, always set to 1.Bit 5 – Reserved for future use, always cleared to 0.Bit 6 – Controls when the Server sends beacons for Client synchronization. This bit is configurableto send a beacon after every HOP or after 2.5 seconds has elapsed since the Server’s Hosthas sent data. This bit can used to substantially decrease the amount of time it takes Clientsto synchronize with the Server.3.2.6.2 Configuration CommandsThe configuration commands allow the Host to read and write EEPROM transceiver configurationparameters. The LX2400S looks at the first byte of a sequence from the Host. If the first byte is theCONFIGURATION START BYTE, and the TST_MODE pin is pulled low at the connector, the LX2400S willenter Configuration Mode. The Host can then read and write parameters using the EEPROM BYTE READand EEPROM BYTE WRITE commands. The command begins with Byte 0. All bytes are echoed back tothe Host as they are received. The Host must not assert TE when using this mode. To exit ConfigurationMode the Host must perform a hardware or power-on reset.3.2.6.2.1 CONFIGURATION START BYTE commandThis byte is sent once by the Host to enter Configuration Mode. After receiving this byte from the Hostwith the TST_MODE pin pulled low at the connector, EEPROM read and write commands can be sent to theHost. The length byte must be set to 01H. Only single byte reads/writes are allowed. Byte 0 = 065H3.2.6.2.2 EEPROM BYTE READ commandThe read routine includes the read command, address, and length bytes. Upon receiving this command, theLX2400S will transmit the desired data from the address requested by the Host. The length byte must be setto 01H. Only single byte reads are allowed.Byte 0 = 0C0H Read CommandByte 1 = 0xxH Address (from TABLE 2)Byte 2 = 01HLength = 01H
THEORY OF OPERATION 09/22/00 Preliminary 153.2.6.2.3 EEPROM BYTE WRITE commandThe write routine includes the write command, address, length, and data bytes. Upon receiving thiscommand, the LX2400S will write the data byte to the address specified but will not echo it back to the Hostuntil the EEPROM write cycle is complete. The write can take as long as 10ms to complete. Following thewrite cycle, the LX2400S will transmit the data byte to the Host. The WR_ENA on the connector must bepulled low to enable the write prior to issuing this command or the write will not occur. The length byte mustbe set to 01H. Only single byte writes are allowed.Byte 0 = 0C1H WRITE CommandByte 1 = 0xxH Address (from TABLE 2)Byte 2 = 01HLength = 01HByte 3 = 0xxH DataNOTE: The WR_ENA pin on the connector should only be pulled low before sending an EEPROM BYTEWRITE command and must be held low until the data byte is echoed to the Host.Data RatesVarious data rates, timings, and system architecture need to be considered when determining Overall SystemThroughput in a RF data system. The Host controls the Serial Interface Data Rate. The LX2400S has a fixedRF Data Rate. The Effective Data Transmission Rate is determined from both Host and LX2400S operation.3.2.7.1 Serial Interface Data RateThe Serial Interface Data Rate is programmable by the Host. This is the rate the Host and the LX2400Scommunicate over the Serial bus. Typical values range from 1200bps to 57,600bps. The only supportedmode is asynchronous – 8-bit, No Parity, 1 Start Bit, and 1 Stop Bit.3.2.7.2 RF Data RateThe RF Data Rate is the rate the LX2400S transmits and receives over the RF link. It is fixed at 144,000bps, 8-bit, Parity, 1 Start Bit, and 1 Stop Bit.
THEORY OF OPERATION 09/22/00 Preliminary 163.2.7.3 Effective Data Transmission RateThe maximum Effective Data Transmission Rate (EDTR) is defined as the rate of one-way continuoustransmission of data packets sent by a Host. It includes the transmitter turn-on and turn-off delays, HOPtime, Host data byte timing and the number of bytes per packet sent by the Host. Beacon timing is not usedin this calculation -- since it is only transmitted when data has not been received by the LX2400S from theHost for approximately 2.5 seconds. Data from the Host is transmitted on the RF link as it is received fromthe Host assuming the system is in sync and the RE pin is in the active state (if enabled). The followingexample illustrates the EDTR at 57,600bps assuming a 32-bit CRC is included with the Host system databytes.EXAMPLE:Example data packet:NPSL = Number of Host preamble, sync and length bytes = 6NHSD = Number of Host system data bytes = 192NHED = Number of Host error detection bytes = 4TXON* = Transmitter on delay = 1msTXOFF* = Transmitter off delay = 1msHTM* = Hop overhead in a 1 second period = 8.34msBAUDRATE = Serial Interface Baud Rate = 57,600bpsCalculations:IBT = Interface byte time = 10/BAUDRATE = 0.174msIGT = Interface Byte gap time = 0PKT = Packet time = (NPSL + NHSD + NHED) * (IBT +IGT) = 35.07msEDTR = (1-HTM) * NHSD/(TXON+TXOFF+PKT) = (1-0.00834) * 192/37.07E-03 = 5136 bytes persecond or 51360 bits per second. Efficiency = (51360 /57600)*100 = 89%*Timing is preliminary3.2.7.4 Overall System ThroughputThe maximum Overall System Throughput (OST) is related to the EDTR and the Host’s systemimplementation. Typical systems implement an acknowledgement of received data. This can take the form ofeither an immediate or delayed response (a response acknowledging many packets). In a polled system,where the Server sends a packet to the Client Host and waits for data to be returned, the Server Host usuallydoes not require separate acknowledge packets because the returned data becomes the acknowledgement.Other systems, which transmit non-critical or repeated data, may not use any form of acknowledgement.
THEORY OF OPERATION 09/22/00 Preliminary 17The following examples give OST for 3 different systems and uses the values from the previous section.Other systems are possible:1 – POSITIVE ACK SYSTEM -- An acknowledgement response packet for each packet received.Additional example data:NHRD = Number of Host system response bytes = 3 (e.g. command and two address bytes)Calculations:PKT = Packet time = (NPSL + NHSD + NHED) * (IBT + IGT) = 35.07msRSPT = Response time = (NPSL + NHRD + NHED) * (IBT + IGT) = 2.26msOST = (1-HTM) * NHSD / (TXON+ PKT + TXOFF + TXON + RSPT + TXOFF) / NHSD =(1-0.00834) * 192/41.33E-03 = 4607 bytes per second or 46070 bits per second. Efficiency = (46070 /57600) *100 = 80%2 – POLLED SYSTEM -- An acknowledgement response via returned Host data.Additional example data:NHSDServer = Number of Host system data bytes = 192NHSDClient = Number of Host system data bytes = 192Calculations:PKT = Packet time = (NPSL + NHSD + NHED) * (IBT + IGT) = 35.07msOST = (1-HTM) * (NHSDServer + NHSDClient )/((TXON+TXOFF+PKT)*2) = (1-0.00834) * 384/74.14E-03 = 5136 bytes per second or 51360 bits per second Efficiency = (51360 /57600) *100 = 89%3 – REPEATED DATA SYSTEM --No acknowledgement response.OST = EDTR = 51360 bits per secondEfficiency = (51360 /57600)*100 = 89%*Timing is preliminary
INTERFACIING TO THE LX2400 09/22/00 Preliminary 184. Interfacing to the LX2400S4.1 OPERATING MODESThe LX2400S uses an 8-bit programmable asynchronous serial interface to communicate to a Host. Theinterface uses one start bit, eight data bits, and one stop bit. Only the interface baud rate is programmableby the Host.A typical system consists of one LX2400S operating in Server Mode (LX2400S Server) communicating withone or many LX2400S(s) operating in Client Mode (LX2400S Client). In this architecture, Clientscommunicate with a single Server. Clients do not communicate with other Clients. Data transmitted by aServer is received by all of the Clients that are in-range. The Server receives the data sent by the Client. Allprotocol functions (retries, addressing, CRCs, etc.) are performed by the Host software. All frequencyhopping and synchronization is provided automatically by the LX2400S without Host intervention.The Firmware in the LX2400S is operating in one of five modes. The Host can determine through hardwareand/or software what mode the LX2400S is operating in using the DSR pin or the software XON/XOFF data.4.1.1 RECEIVE MODEThe LX2400S is in RECEIVE MODE, by default, when it is not in any other operating mode. While in thismode, the LX2400S is looking for valid preamble and sync data bytes from a transmitter. When validpreamble and sync bytes are detected, the LX2400S will transmit data received on the RF link to the Hostusing the HOST RECEIVE FRAME FORMAT. A Client LX2400S will only accept data from its Host whenit is in-range of a valid LX2400S Server.4.1.2 TRANSMIT MODEThe Host software initiates transmission of a data packet on the RF link by lowering TE, waiting for CTS togo low, followed by sending the specified preambles bytes, sync byte, data length, and data. Both maximumdata byte gaps and packet times must be adhered to. At the end of the transmission TE must return to aLogic Level High. After TE is taken high by the Host, the LX2400S will drive CTS high. This indicates theLX2400S is returning to RECEIVE MODE. The Host software must perform MAC layer functions (retries,addressing CRCs, etc.). If the Client LX2400S is not in-range of a LX2400S Server, TRANSMIT MODEwill not be entered. The Client LX2400S will not respond with CTS. The following sequence transmits a packet on the RF link:1. The Host drives the TE pin low.2. The LX2400S responds by driving CTS low.3. The Host sends serial bytes as specified in the HOST TRANSMIT FRAME FORMAT. TheLX2400S transmits the HOST TRANSMIT FRAME FORMAT on the RF link as it receives eachbyte from the Host.4. The Host drives TE high after the last byte is received by the LX2400S.5. The LX2400S responds by driving CTS high and returns to RECEIVE MODE.
INTERFACIING TO THE LX2400 09/22/00 Preliminary 194.1.3 CONFIGURATION MODEThe CONFIGURATION MODE is used to read and write the EEPROM -- allowing the Host to set channels,baud rates, etc. See TABLE 2. While in this mode the LX2400S will not receive any data over the RF link.TE and CTS are not used. The Host enters this mode with the following sequence:1. The Host pulls the TST_MODE pin low.2. The Host sends the CONFIGURATION START BYTE to the LX2400S.3. The Host pulls the WR_ENA pin low if writing.4. The Host sends the EEPROM BYTE READ or the EEPROM BYTE WRITE command.5. The Host Repeat Steps 3 and 4 until done.6. The Host drives pins TST_MODE and WR_ENA high.7. The Host resets the LX2400S.NOTE: The WR_ENA pin should not be permanently tied low as brownout conditions can corrupt EEPROMdata.4.1.4 HOPPING MODEThe HOPPING MODE is controlled by the LX2400S. The LX2400S hops approximately every 100ms . Duringthis time, the LX2400S is changing the frequency it will use to transmit and receive. The LX2400S informsthe Host of the hop by asserting the DSR pin at the connector or by using the XON/XOFF received bytes ifenabled in the EEPROM in the sequence. The DSR pin will frame the hopping procedure. When the Hostsoftware detects the hopping mode during a transmission of a packet, it can be assumed that the packet didnot reach it’s destination and the Host should re-send the packet.4.1.5 BEACON MODEBeacon mode applies to a LX2400S Server only. In order to synchronize the hopping of all LX2400Ss in asystem, the LX2400S Server will transmit beacon data consisting of system timing information at a periodicrate. This occurs by default after transceiver reset and initialization. The beacon is transmitted once perHOP time -- immediately after a HOP occurs. Beacons are not transmitted when the LX2400S Server istransmitting data from the HOST over the RF link. If the LX2400S Server does not receive data forapproximately 2.5 seconds from the Server Host, the LX2400S Server will resume transmitting Beacons. Thisprovides continuous synchronization data for the LX2400S Clients. The beacon data is not transmitted oravailable to either the Client or Server Host. The beacon takes approximately 2ms to complete. The LX2400Sindicates that it is executing a HOP with the DSR pin and a XON/XOFF sequence if enabled.The Server Host can ignore the HOP if the Host software has retry capabilities or can tolerate non-delivery of data. Empirical testing shows a 3 to 5 percent loss of data when ignoring the HOP indicators.(See “LX2400S Hopping and Beacon Timing” in Section 4.5)
INTERFACIING TO THE LX2400 09/22/00 Preliminary 204.2 LX2400S GLOBAL Timing ParametersTable 4 – Global Timing ParametersTiming is preliminary and not guaranteed for productionNAME MIN TYP Max COMMENTtRT TBD 1ms Receive to Transmit settling time – Transmit OfftTR TBD 1ms Transmit to Receive settling time – Transmit OfftTXMOD 20ms Longest amount of time to continuously send datatPackG 1ms TX Packet GaptByteG 1 byte time Maximum Byte Gap4.3 LX2400S Transmit Mode TimingTECTSRXDRE55 55 55 3A Length H Length L Host DataHost DataD0D1 D2D3D4 D5 *RE can be ignored if not enabled.Table 5 – Transmit Mode TimingNAME MIN TYP MAX COMMENTD0 20ms Timing is preliminary and not guaranteed for productionD1 1ms Timing is preliminary and not guaranteed for productionD2 10us Timing is preliminary and not guaranteed for productionD3 0Timing is preliminary and not guaranteed for productionD4 0Timing is preliminary and not guaranteed for productionD5 0Timing is preliminary and not guaranteed for production
INTERFACIING TO THE LX2400 09/22/00 Preliminary 214.4 LX2400S Configuation Mode TimingTST_MODERXDWR_ENAUP_RESET65 EEPROM R/W CommandsEEPROM R/W CommandsD0D1D2D3 D4* WR_ENA is used only when writing to EEPROMTable 6 – Configuration Mode TimingNAME MIN TYP MAX COMMENTD0 0Timing is preliminary and not guaranteed for productionD1 1ms Timing is preliminary and not guaranteed for productionD2 10ms When executing an EEPROM WRITED3 1ms Timing is preliminary and not guaranteed for productionD4 4ms Timing is preliminary and not guaranteed for production4.5 LX2400S Hopping and Beacon TimingDSRRF_TXDTECTSRXDTXDHOST TX FRAMED0D1D2D3D4D5D6XON XOFFHOP HOPXONBEACONBEACON* Beacons are only transmitted if RXD has been idle for approximately 2.5 seconds.* Diagram shows Host synchronous with the HOP.
INTERFACIING TO THE LX2400 09/22/00 Preliminary 22Table 7 – Hopping and Beacon TimingNAME MIN TYP MAX COMMENTD0 100ms Timing is preliminary and not guaranteed for productionD1 1ms Timing is preliminary and not guaranteed for productionD2 1ms Timing is preliminary and not guaranteed for productionD3 1ms Timing is preliminary and not guaranteed for productionD4 1ms Timing is preliminary and not guaranteed for productionD5 20ms Timing is preliminary and not guaranteed for productionD6 1ms Timing is preliminary and not guaranteed for production
MECHANICAL 09/22/00 Preliminary 235. Mechanical Overview5.1 TransceiverThe LX2400S measures 1.65” x 2.65”. Critical parameters are as follows:J1 – 20 pin connector (lower left edge) SAMTEC TMM-110-01-L-D-SM (4) Mounting holes are 0.100” diameter.Figure 1. Mechanical Overview of LX2400S5.2 AntennaThe LX2400S-3A and the LX2400S-10A incorporate an Aerocomm NZH antenna on the transceiver board.The NZH is a highly efficient, microstrip, center-fed dipole design with a broad pattern. The NZH ismatched to the RF circuits yielding superior performance. This is important when using low-power RFtransceivers because a poor or marginally matched antenna will drastically reduce the operating distancebetween transceivers. Special consideration must be given to the antenna placement in the OEM’s design.Materials in close proximity (up to 4 inches) can affect antenna performance. Aerocomm can assist the OEMwith fine-tuning the antenna and/or enclosure that will incorporate the transceiver. Contact your AeroCommOEM salesman or OEM customer support for assistance. The LX2400S-10 and LX2400-150 incorporate anMMCX jack (Telegartner P/N J0134A0081) allowing the OEM to select antennas with specificcharacteristics.
ORDERING INFORMATION 09/22/00 Preliminary 246. Ordering Information6.1 Product Part NumbersLX2400S-3, LX2400S with 3mW output power, interface data rates to 19,200bps, integrated antennaLX2400S-10, LX2400S with 10mW output power, interface data rates to 57,600bps, MMCX ant connectorLX2400S-150, LX2400S with 150mW output power, interface data rates to 115,200bps,6.2 Developer Kit Part NumbersSDK-LX2400S-3, Includes (2) LX2400S-3A transceivers, (2) RS232 Serial Adapter Boards, (2) 6Vdcunregulated power supplies, (2) Serial cables, configuration/testing software, Integration engineeringsupportSDK-LX2400S-10, Includes (2) LX2400S-10 transceivers, (2) RS232 Serial Adapter Boards, (2) 6Vdcunregulated power supplies, (2) Serial cables, (2) S191FL-5-RMM-2450S dipole antennas with 5” pigtailand MMCX connector, configuration/testing software, Integration engineering supportSDK-LX2400S-150, Includes (2) LX2400S-150 transceivers, (2) RS232 Serial Adapter Boards, (2) 6Vdcunregulated power supplies, (2) Serial cables, (2) S191FL-5-RMM-2450S dipole antennas with 5” pigtailand MMCX connector, configuration/testing software, Integration engineering support

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