CRESCENDO UHF HALF-DUPLEX USER MANUAL
Contents Crescendo UHF Half-Duplex User Manual DISCLAIMER © 2013 RF Innovations Pty Ltd. All rights reserved. RF Innovations reserves the right to make improvements on the product in this manual at any time without notice. No part of this manual may be produced, copied, translated, or transmitted in any form or by any means without the written permission of RF Innovations. Information provided in this manual is intended to be accurate and reliable.
Contents Contents 1. Introduction ............................................................................................................................................................................. 6 2. Installation ................................................................................................................................................................................ 7 2.1 General considerations ...........................................................................
Contents 5.6.1 5.6.2 5.6.3 5.6.4 5.6.5 6. Data Quality .............................................................................................................................................................. 31 RSSI .......................................................................................................................................................................... 31 Monitor RSSI ......................................................................................................
Contents A.2.1 Input Current ............................................................................................................................................................. 57 A.3 Connector Pin Assignment ............................................................................................................................................. 58 A.3.1 Main Serial Port............................................................................................................................
Introduction 1. Introduction Crescendo is a series of data-driven and packet-driven radio modems for high-speed data applications. This manual is specific to Crescendo UHF Half-Duplex. Some of the relevant features of this model include: UHF band operation (390 MHz - 500 MHz), with approximately 20 MHz switching bandwidth (model specific). 5 W (+ 37 dBm) maximum transmit power Wideband or narrowband channels, with software selectable frequency raster Raw air rate 19.
Installation 2. Installation 2.1 General considerations There are a number of rules to observe when installing a Crescendo. Antenna selection is vital to a good RF link. Different antennas are required depending on the application. Please contact your antenna manufacturer or RF Innovations for correct antenna selection. Antenna placement has a significant impact on RF link performance. In general, higher antenna placement results in a better communication link.
Installation 2.3 Safety and Compliance 2.3.1 Human Exposure to Emissions To limit human exposure, the following guidelines should be observed: 1. Take reasonable precautions in any installation to maintain a clearance of no less than 2 m (two metres) from the antenna to any person. 2. Do not apply power to the device unless the clearance described in 1 above has been allowed. The guidelines above apply when transmitting at maximum power, with an antenna gain of up to 13 dB.
Configuration 3. Configuration 3.1 Overview The Crescendo provides five user interfaces that allow the radio to be configured and its performance to be monitored: 1. Cruise Control management interface: All radio configuration and diagnostics parameters can be accessed using the Windows-based Cruise Control Graphical User Interface (GUI). 2. Terminal menu interface: A menu system is available on both of the Crescendo’s serial ports.
Configuration 3.2 Cruise Control The following sections briefly outline how to use Cruise Control with the Crescendo. For more information, see the Cruise Control Manual. Figure 1 below is a typical screenshot of the Cruise Control Configuration Tool. Figure 1: Cruise Control Configuration Tool 3.2.1 Installation The requirements for using the Cruise Control application are: Pentium III+ Windows based machine. At least 1 available serial port.
Configuration Changes made to the configuration or protocol mode of the serial port which Cruise Control is using do not take effect immediately. They take effect when the disconnect button in Cruise Control is pressed, or the radio is reset. The main port of the Crescendo is typically used for data, but may also be used for Cruise Control if it is configured in Hayes protocol.
Configuration 3.4 Hayes AT Command Interface The Crescendo radio supports Hayes ATtention commands. These are used to query radio configuration and performance parameters, set radio configuration, and establish communication links between radios over the air. For a port to accept AT commands it must be first in local command mode. See section 6.5.3 on page 37 for information on enabling and disabling local command mode.
Configuration 3.5 Front Panel Interface The front panel interface allows for real-time monitoring of radio parameters without external equipment. The front panel can also be used to enable the menu on the Crescendo’s auxiliary port regardless of the current serial port configuration. There are six front panel modes. To select a front panel mode, press the front panel button. The current panel mode is shown by lighting a single red LED.
Configuration Solid green when a connection is established with a remote radio. Flashes red when a point-to-point link goes from the connected to not connected state. Flashes green when the radio is operating normally. Flashes red when a fault has occurred. Faults are displayed in Cruise Control under Main -> Diagnostics -> Faults.
Configuration (3) Tx Serial Data Flashes green when serial data is transmitted from the Crescendo on either serial port. (4) Rx Serial Data Flashes green when serial data is received by the Crescendo on either serial port. Flashes red when a receive error occurs on either serial port. See section 4.4 on page 19 for serial statistics. (5) RTS Green when the RTS input is low, red when it is high. (6) CTS Green when the CTS output is low, red when it is high.
Serial Port Operation 4. Serial Port Operation 4.1 Overview The Crescendo radio has two DCE RS-232 serial ports with DB9 connectors. The serial port pin outs can be found in Appendix A.3 on page 58. The main port supports: TX, RX, and GND. RTS and DTR inputs. CTS and DCD outputs. While the auxiliary port supports: TX, RX, and GND. Both serial ports support over the air data transfer. In general, due to the presence of control lines, the main port should be used as the main data port.
Serial Port Operation 4.2 Configuration Main -> Serial Port -> Settings Both main and auxiliary serial ports support the following configuration options: 4.3 Baud rate: 300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600 or 115200. Data bits: 7 or 8 Parity: None, odd, or even Stop bits: 1 or 2 Advanced Features 4.3.
Serial Port Operation Main -> Serial Port -> Settings 4.3.2 Packetiser Timers Many protocols delimit packets of data by silence on the communications line for a set period of time. A common example of such a protocol is Modbus. Due to the framed structure over the air when the radio is in packet driven mode, packetiser timers should be used to support protocols and increase the efficiency of data transmission. Packetiser timers can be set between 0 and 10000ms.
Serial Port Operation Channel Width TX Timer Narrowband >= 25ms Wideband >= 13ms Table 8: TX packetisation timers for different channel widths Using packetiser timers will increase the latency induced by the radio system, as no part of the packet can be transmitted until it has been fully received. 4.4 Main -> Serial Port -> Settings Statistics Statistics are maintained for each serial port and these can be used to analyse and debug problems. The statistics are given in Table 9.
Serial Port Operation These statistics can be used to isolate a number of potential problems in a Crescendo system. A large number of Rx framing errors indicates that the radio serial port configuration (baud, data bits, parity, and stop bits) does not match the serial port configuration of the DTE. A large number of Rx overflow errors indicate that the DTE is supplying data faster than it can be transferred over the air.
Radio Operation 5. Radio Operation This section describes the two modes of Crescendo operation: data and packet-driven. These modes underlie the different protocols supported, described in section 6. Regardless of the mode used serial characters are assembled in small blocks for the purpose of Forward Error Correction (FEC). These blocks are then subject to error coding / interleaving, and protected by a CRC.
Radio Operation If a payload packet or ACK is lost, resulting in the base radio not receiving the ACK, the source radio retransmits the payload packet. This continues until the number of retries for the packet has been exhausted. 5.2.1 Data Path Internally, the Crescendo stores a set of payload frames that are waiting to be transmitted, and a set of payload frames that have been received but not yet processed.
Radio Operation Link quality: The quality of a link can have a substantial impact on the latency induced by the radio. The Crescendo will retry packets that become corrupted due to RF interference, configurable between 0 and 20 retries. The more retries that are required to successfully transmit a packet, the greater the latency induced. This is only applicable to packet driven mode.
Radio Operation Main -> Radio 5.3.2 Tx Power The transmit power of the Crescendo can be configured to transmit at fixed levels into a 50 load: 0dBm (1 mW) +20dBm (100 mW) +27dBm (500 mW) +30dBm (1W) +36dBm (4W) +37dBm (5W) A maximum power setting can be configured by the distributor to limit the allowable power for a given combination of radio and antenna. 5.3.
Radio Operation 9 N/C Gnd Gnd Gnd 10 N/C Gnd Gnd N/C 11 N/C Gnd N/C Gnd 12 N/C Gnd N/C N/C 13 N/C N/C Gnd Gnd 14 N/C N/C Gnd N/C 15 N/C N/C N/C Gnd 16 N/C N/C N/C N/C Table 11: Channel selection via I/O module In the table above, “Gnd” indicates that the pin should be connected to ground, and “N/C” means that the pin should not be connected. Note that channel 16 is selected by default when no pins are connected and “I/O Selects Channel” is enabled.
Radio Operation Repeaters in Network: The maximum number of repeaters through which a packet must go before reaching its destination. Note that depending on network topology, this may be less than the total number of repeaters in the network. This parameter should be set the same for all units in the network. The repeaters in network setting can be configured between 0 and 65535. Max Packet Size: This is the maximum number of bytes of payload a packet will have.
Radio Operation When allocating radio addresses, a recommended convention is to reserve the first two decimal digits as the subnet number, and the last three digits for individual radios residing within the subnet. For example, consider the scenario shown in Figure 5, and the address allocation given in Table 12.
Radio Operation Network A Remote 1A Base 1A Remote 2A Remote 1B Base 1B Remote 2B Network B Figure 6: Co-located networks When co-locating Crescendo networks it is important to observe the following: If the co-located networks operate on different Tx and Rx frequencies, RF interference will not occur. This is the ideal situation. If the co-located networks share Tx or Rx frequencies, the networks must have different network addresses.
Radio Operation When setting up a network with store-and-forward repeaters, it may be necessary to adjust the following parameters on units in the network: Repeaters in Network. Wait for Carrier. Routing Tables Routing traffic to take advantage of store-and-forward repeaters is covered in section 5.5 on page 29. 5.
Radio Operation Main -> Radio -> Network -> Routing Table 5.5.2 Routing Table Complete control can be maintained over the routing of data through a Crescendo network by configuring the routing table. The routing table consists of 16 entries on each unit which specify rules to apply for data with destination addresses within a particular range. The destination of point-to-point data is simply the point-to-point destination address (see section 6.3 on page 35).
Radio Operation 5.6 Diagnostics 5.6.1 Data Quality Main -> Link Control The Crescendo continually measures the ‘quality’ of the received signal by comparing the received waveform against an internally generated ‘ideal’ baseband signal. The result is a value from 0-255 that is indicative of the quality of the data. In general, a data quality of greater than 100 is good, and less then 50 is poor. The following data quality values are kept: Data Quality: The most recent data quality measurement.
Radio Operation BASEBAND STATISTICS Name Number Description Tx Sync 0 The total number of symbol/frame synchronisations sent for the start of a packet transmission. Tx ReSync 1 The total number symbol/frame resynchronisations. Rx Sync 2 The total number of symbol/frame synchronisations received for the start of a packet. Rx ReSync 3 The total number of symbol/frame resynchronisations received.
Radio Operation PACKET DRIVEN MAC STATISTICS Name Number Description Tx Bytes 0 The number of bytes that have been transmitted. Rx Bytes 1 The number of bytes that have been received and processed. Tx Packets 3 The total number of packets transmitted correctly. Rx Good Packets 4 The total number packets that have been received correctly.
Protocol Operation 6. Protocol Operation 6.1 Overview Both of the Crescendo’s serial ports can be independently configured with different protocol modes. Protocol modes serve two purposes: Provide methods for configuring the radio for operation, and for interrogating it in order to determine current operational status. Allow the Crescendo radio to determine how data received on its serial ports is to be converted into RF packets.
Protocol Operation 6.3 Point-to-point Protocol Main -> Protocol The point-to-point protocol establishes a connection between two end points. Both end points must have the point-to-point protocol selected on the same serial port, and have the point-to-point destination set to the remote radio modem address. There are two operational modes configurable for the point-to-point protocol: Connection Based: This mode of operation provides a connection oriented link.
Protocol Operation 6.4.2 Local Mode Both point-to-point and point-to-multipoint protocol modes allow local command mode to be entered using the escape sequence (section 6.5.3 on page 37), or by using the DTR line on the main port (section 6.5.5). Returning to online mode is achieved using the online command (ATO). The protocol can also be configured to start in local command mode when power is applied. For data to be transferred between two end units, both units must be online, not in local command mode.
Protocol Operation 6.5.2 Answering The Crescendo provides two options for answering dial-up calls: Auto-answer: In auto-answer mode, when a connection request is made the Crescendo will output a configurable number of RING responses on the destination, then automatically connect. Manual answer: When in manual answer mode, the Crescendo will output a RING response on the destination once per second until the ATA command is received, at which point the connection is established.
Protocol Operation 6.5.5 DTR Modes In addition to the AT commands that are used to control the dial-up connection, DTR may be configured to provide similar functionality. Only the main port supports DTR, so the setting for DTR mode on the auxiliary port Hayes protocol is not used. There are four available DTR modes: Ignore DTR: DTR is not used to control the Hayes communications settings. Hangup on DTR Low: If DTR is low then the radio will hang-up the current connection.
Protocol Operation 6.6 Modbus RTU Protocol Main -> Protocol -> Modbus When using the Modbus RTU protocol, the Crescendo expects Modbus RTU packets on the serial port in the following format. Start T1-T2-T3-T4 Address (1 byte) Function (1 byte) Data (0…251 bytes) CRC (2 bytes) Figure 8: Datagram protocol packet format The fields of a Modbus packet are: Start: A silent interval of at least 3.5 character times. Address (8-bit): The address of the slave unit in the Modbus transaction.
Protocol Operation 6.7 Main -> Protocol -> DNP Distributed Network Protocol (DNP) The Crescendo supports the Distributed Network Protocol (DNP) as defined by the DNP Users Group (http://www.dnp.org/). The packet structure for a DNP packet expected on the serial port is shown below. Start 0x0564 Len (8) Ctrl (8) Destination (16) Source (16) CRC (16) Data (0…16) … CRC (16) Figure 9: DNP packet format Start (16-bit): A fixed start of packet marker, always 0x0564.
Protocol Operation DP (2-bit): The destination serial port. This can be either 00 for the main port or 01 for the auxiliary port. SP (2-bit): The source serial port. When sending a packet to a radio, this field does not need to be set. The value will automatically be set to the serial port the packet was inserted on. Res (4-bit): Reserved for future use. This field should be set to all zeros. Data: The data to be transmitted.
Protocol Operation Hayes dial-up Connection established Connected if a path exists between the local and remote device. Not Connected if there is no communications path. No connection established Not Connected Datagram N/A Table 17: RF link status for different protocol modes Whenever the protocol mode on a serial port is temporarily disabled (such as when the menu is enabled on the port, or when the Cruise Control application has been started), the RF Link Status will be displayed as N/A. 6.
Protocol Operation *** Protocol Mapping Menu *** |Type |First Addr |Last Addr |Radio Addr | |-------------------|-------------------|-------------------|-------------------| (0) |Single | 1| 0| 1001| (1) |Unused | 2| 0| 1002| (2) |Single | 3| 0| 1003| (3) |Mapped | 4| 10| 1004| (4) |Grouped | 11| 20| 1011| (5) |Unused | 0| 0| 0| (6) |Unused | 0| 0| 0| (7) |Unused | 0| 0| 0| (8) |Unused | 0| 0| 0| (9) |Unused | 0| 0| 0| (A) |Unused | 0| 0| 0| (B) |Unused | 0| 0| 0| (C) |Unused | 0| 0| 0| (D) |Unused | 0| 0|
Applications 7. Applications This section presents typical Crescendo usage scenarios. The aim of these scenarios is to illustrate radio configuration. 7.1 Point-to-point Networks 7.1.1 Basic Point-to-point Network A basic point-to-point network consists of two units configured such that the point-to-point destination of one unit is the address of the other. This scenario is shown in Figure 13.
Applications 7.1.2 Multiple Port Point-to-point Network Two point-to-point destinations can be used by configuring the point-to-point protocol on both serial ports of base unit, and then having two remotes each connected to a different port. This scenario is shown in Figure 15.
Applications 7.1.3 Multiple Destination Point-to-point Network Multiple destinations can be used by configuring any number of remote units and then changing the destination address of the base unit using local command mode. This scenario is shown in Figure 15.
Applications 7.1.4 Point-to-point Network with Repeater Repeaters can be used to extend the range of a point-to-point network, as shown in Figure 20.
Applications 7.2 Point-to-multipoint Networks 7.2.1 Basic Point-to-multipoint Network A basic point-to-multipoint network is shown in Figure 17.
Applications 7.2.2 Point-to-multipoint Network with Roaming Remote In some applications the remote unit may be mobile, and needs to ‘roam’ between areas of coverage. A point-to-multipoint network configured for this purpose is shown in Figure 18.
Applications 7.3 Hayes Dial-up Networks 7.3.1 Basic Hayes Dial-up Network A basic Hayes dial-up network is given in Figure 19.
Applications 7.3.2 Hayes Dial-up Network with Repeaters Repeaters can be used to extend the range of a Hayes dial-up network, as shown in Figure 20.
Applications 7.4 Modbus/DNP Networks 7.4.1 Basic Modbus RTU Network with Repeater A Modbus network with repeater is shown in Figure 21.
Applications 7.4.
Applications 7.4.3 DNP Network with Repeater A DNP network with repeater is shown in Figure 23.
Applications 7.5 Datagram Networks 7.5.1 Basic Datagram Network A basic datagram network is shown in Figure 24.
Appendix A Technical Specifications Appendix A Technical Specifications A.1 Type Approvals Australia/ New Zealand AS 4295 -1995 Australian Supplier ID: N161 FCC CFR 47 Part 15 and Part 90 FCC ID: P5MRFI450H Industry Canada RSS-GEN, RSS-102, RSS-119 IC: 10592A-RFI450H ETSI (planned) ETS 300 113 Table 18: Type approvals A.
Appendix A Technical Specifications Digital Inputs 0 - 5 V (internal 5 kiloohm pull-up) Input Voltage 9 V to 16 V DC (negative ground) Environmental Specifications Temperature: -10 ºC to +60 ºC Humidity (max): 95% non-condensing at 50 ºC Connectors: Power: Phoenix PH1776508 Main Serial Port: DB9 RS-232 Female Auxiliary Serial Port: DB9 RS-232 Female I/O Module Connector (where present): 5-way terminal block (35mm, screw flange, Phoenix part number 1843826) RF: BNC Female (50 ohm nominal) Table 19: Ra
Appendix A Technical Specifications A.3 Connector Pin Assignment A.3.1 Main Serial Port Pin Function Direction 1 DCD Output 2 RxD Output 3 TxD Input 4 DTR Input 5 GND 6 N/A 7 RTS Input 8 CTS Output 9 N/A Table 21: Main connector pin assignment A.3.
Appendix A Technical Specifications A.3.
Appendix A Technical Specifications Length 188 mm Width 101.6 mm Height 45.
Appendix A Technical Specifications A.3.
Appendix B Management Reference Appendix B Management Reference B.1 Main Configuration Main Page AT Product String The product string. I0 Manufacture Date The date of manufacture. I5 Serial number The serial number of the unit. I6 B.2 Radio Configuration Radio Page AT Address Sets the radio local address, 0-61439 23 S51 Tx Power The output power. 24 S45 RSSI Trip Set the RF signal level for RF data.
Appendix B Management Reference Raster Sets the raster to be used. 24 S57 Current Channel Sets the current channel and corresponding Tx/Rx frequencies to be used. 24 S54 I/O Selects Channel Determines whether active channel can be selected by digital inputs. 24 S180 Channel Tx Frequency Transmit frequency for a channel. 24 S55 Channel Rx Frequency Receiving frequency for a channel.
Appendix B Management Reference B.3 Link Control Configuration and Diagnostics Link Control Page AT Data Quality Shows the current data quality (0-255) 31 I60 Lowest Data Quality Shows lowest data quality received so far (0255) 31 I61 Temperature The temperature of the unit. Average Noise The average RSSI level where no valid carrier is present on the receive channel. 31 I12 Average RSSI The average RSSI level while data is being received.
Appendix B Management Reference B.5 Protocol Mode Configuration and Diagnostics Protocol Page AT Modbus Query Enables configuration and diagnostic parameters to be accessed by Modbus commands. 39 Modbus Address The Modbus address of the radio. 39 Lead-in Count The number of lead-in bytes the radio will discard and not transmit over the air. 34 S73 Data timeout The period of serial silence the radio will wait before it stops transmitting.
Appendix B Management Reference B.6 Diagnostics Diagnostics Page AT I15 Fault The last fault that was reported. Startup Reason Indicates if the radio started normally or due to a watchdog reset. EEPROM Status The state of the EEPROM at start-up. R10 Build Date The date that the firmware was built. R9 Monitor RSSI Puts the radio in a mode when it continuously outputs the RSSI on the current channel (can only be used in menu). Factory Reset Resets all settings to factory defaults.
Appendix C Hayes Reference Appendix C Hayes Reference C.1 General Commands Command ATE Name Echo Notes Returns 1 if Hayes echo is enabled, or 0 if echo is disabled. ATE0 Disables Hayes echo. ATE1 Enables Hayes echo. ATQ Responses Returns 1 if Hayes responses are enabled, or 0 if responses are disabled. ATQ0 Disables Hayes responses. ATQ1 Enables Hayes responses. ATV Verbal Responses Returns 1 if verbal responses are enabled, or 0 if verbal responses are disabled.
Appendix C Hayes Reference AT&T9 Hard Reset Restart system for programming. AT&V View All Registers Outputs the value in all I and S registers. AT&V1 View All I Registers AT&V2 View All S Registers AT&W Save Configuration AT? Enable Menu AT%30 Enable Cruise Control Saves the current configuration to EEPROM. Enables the Cruise Control on the serial port. Wait for 10 seconds after executing with no further data input to return to normal Hayes mode. Table 31: Hayes general commands C.
Appendix C Hayes Reference ATI16[1] Returns the RF link status for the auxiliary port. ATI20[p, s] Serial Port Statistics ATI25[s] Get Baseband Statistic ATI26[s] Get Data Driven MAC Statistic ATI27[s] Get Packet Driven MAC Statistic ATI50 Channel Width Table 33: Hayes I-register commands C.4 S-Registers All serial port configuration and status commands can be executed on either the main port or auxiliary port.
Appendix C Hayes Reference Command Name Notes ATS50 Network Address ATS51 Radio Address ATS52 Point-to-point Destination Address ATS53 RSSI Trip ATS54 Current Channel First channel number is 1, unless Legacy Channel Numbering is enabled, in which case first channel is 0. ATS55[c] Channel Tx Frequency c is the channel number. Frequency in MHz. First channel number is 1, unless Legacy Channel Numbering is enabled, in which case first channel is 0.
Appendix C Hayes Reference Command ATS91 Name Main Port CTS Mode Notes Note that this command cannot have a [p] port specifier. 0: Always High 1: Always Low 2: Mirrors DTR 3: Mirrors RTS 4: Follows Rx Carrier 5: Follows Tx Enable 6: Follows Online ATS92 Get Main Port DTR Note that this command cannot have a [p] port specifier. 0: Line is not asserted. 1: Line is asserted. ATS93 Get Main Port RTS Mode Note that this command cannot have a [p] port specifier. 0: Line is not asserted.
Appendix C Hayes Reference Command Name Notes 0: None 2: Hardware (RTS / CTS) ATS140 Datagram Footer Mode ATS151[a] Routing Table Entry First Address ATS152[a] Routing Table Entry Last Address ATS153[a] Routing Table Hop Address ATS160 Repeaters in Network ATS170 Max RF Packet Size ATS180 I/O Selects Channel 0: Fixed 1: CRC-32 0: Disabled 1: Enabled Table 34: Hayes S-register commands C.
Appendix D Factory Defaults Appendix D Factory Defaults Group Radio Network Channel Parameter Default Value Address 1000 Tx Power 30 dBm RSSI Trip -110 Network Address 0 Store and Forward Repeater Disabled Repeaters in Network 0 Max Packet Size 1024 bytes Broadcast Retransmissions 5 Singlecast Retries 5 Routing Table Current Channel 1 Channels (Tx and Rx) 1-16: As set by factory (not reset with factory reset) I/O Selects Channel Disabled Main Flow Control None Main
Appendix D Factory Defaults Datagram Hayes Dial-up Start In Local Mode Main: Disabled Aux: Enabled Point-to-point Mode Connection Based Receive Addressing Strict Footer Mode CRC-32 Wait for Carrier 10 seconds Auto-Answer On Rings Before Answer 3 DTR Mode Ignore Echo On Response On Verbal Responses On Escape Guard Time 1000 ms Escape Guard Character + Lead-in Count 0 Data Timeout 2 ms Level Information Data Driven Event Log Table 36: Factory defaults Crescendo UHF Half-Du
Appendix E Product Identification Table Appendix E Product Identification Table Table 37 shows the Crescendo product identification. The green shaded items are the available configuration. This table should be used when ordering a Crescendo radio modem.
Appendix F Glossary Appendix F Glossary ACK Acknowledgement ARQ Automatic Repeat Request BNC British Naval Connector CRC Cyclic Redundancy Check CTS Clear To Send DCD Data Carrier Detect DCE Data Communications Equipment (radio modem) DTE Data Terminal Equipment (computer device) DTR Data Terminal Ready RF Radio Frequency RSSI Received Signal Strength Indicator RTS Request To Send Rx Receive Tx Transmit UHF Ultra High Frequency VHF Very High Frequency FER Frame Error Rate T
Index Index Addressing.......................................................................... 23 Answering .......................................................................... 37 Applications ....................................................................... 44 AT Commands ................................................................... 12 Auto-answer ....................................................................... 37 Broadcast retransmissions .......................................
Index Wait for Carrier ............................................................. 65 Manual answer ................................................................... 37 Max Packet Size ................................................................. 26 Menu .................................................................................. 11 Mode 1 ............................................................................... 13 Mode 2 ..................................................................
