User Manual 905U-D Radio Modem ELPRO Technologies Pty Ltd, 9/12 Billabong Street, Stafford Q 4053, Australia. Tel: +61 7 33528600 Fax: +61 7 33528677 Email: sales@elprotech.com Web: www.elprotech.
905U-D Radio Modem User Manual Thank you for your selection of the 905U-D radio modem. We trust it will give you many years of valuable service. ATTENTION! Incorrect termination of supply wires may cause internal damage and will void warranty. To ensure your 905U-D enjoys a long life, double check ALL your connections with the user’s manual before turning the power on. Caution! For continued protection against risk of fire, replace the internal module fuse only with the same type and rating.
Important Notices FCC Notice: This user’s manual is for the ELPRO 905U-D radio telemetry module. This device complies with Part 15.247 of the 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.
905U-D Radio Modem User Manual Important Notice ELPRO products are designed to be used in industrial environments, by experienced industrial engineering personnel with adequate knowledge of safety design considerations. ELPRO radio products are used on unprotected license-free radio bands with radio noise and interference.
Important Notices How to Use This Manual To receive the maximum benefit from your 905U-D product, please read the Introduction, Installation and Operation chapters of this manual thoroughly before putting the 905U-D to work. Chapter Four Configuration details the configurations available and explains the diverse operation of the product in detail. Chapter Five Specifications details the features of the product and lists the standards to which the product is approved.
905U-D Radio Modem User Manual 3.6.1 Auto-Connect Controlled Mode ................................................................................. 26 3.6.2 Low Power Auto-Connect Mode ............................................................................... 26 3.6.3 Single-Connect Controlled Mode .............................................................................. 26 3.6.4 Fast Operation Controlled Mode ............................................................................... 27 3.
Chapter One Introduction Chapter One INTRODUCTION 1.1 General The 905U-D radio modem module has been designed to provide flexible and reliable radio modem functions, at an economical price. Radio modems transmit serial data over a long distance via radio. The serial data is not changed - the output data is the same as the input data. Although the 905U-D is intended to be simple in its application, it also provides many sophisticated features.
905U-D Radio Modem User Manual The operation of the 905U-D radio modem is relatively simple. As data is received at the serial port, the data is transmitted on the radio channel. Up to 530 bytes of data can be transmitted in one transmission. The radio transmission commences when the first data byte is received, and ends when there are no more data bytes in the input buffer, or when the number of bytes transmitted equals the maximum message length (user configurable - default 530 bytes).
Chapter One Introduction PLC 905U-D PLC PLC 905U-D PLC RS485 905U-D Transparent mode is “point-to-multipoint” communications, suitable for a host device which is able to communicate on a multi-drop “bus” type network. An example of an application is the use of radio modems to extend a PLC RS485 network. The serial messages from the PLC’s already include PLC addressing and error detection/correction to control the flow of data. 1.
905U-D Radio Modem User Manual to set destination addresses would be a central computer polling data loggers for periodic information. 1.4 Repeater Units A 905U-D unit may be used as a repeater to re-transmit radio messages. The purpose of a repeater unit is to extend radio range. In transparent mode, there can be an unlimited number of repeaters, however with some conditions (refer to Section 3.5). The repeater in transparent mode will repeat every transmission it receives.
Chapter Two Installation Chapter Two 2.1 INSTALLATION General The 905U-D module is housed in an rugged aluminum case, suitable for DIN-rail mounting. Terminals will accept wires up to 12 gauge (2.5 sqmm) in size. All connections to the module must be SELV. Normal 110-240V mains supply should not be connected to any terminal of the 905U-D module. Refer to Section 2.3 Power Supply. Before installing a new system, it is preferable to bench test the complete system.
905U-D Radio Modem User Manual tolerated for shorter distances. For very short distances, it is possible to mount the antennas inside buildings. An obstructed path requires testing to determine if the path will be reliable refer the section 6 of this manual. Where it is not possible to achieve reliable communications between two 905U modules, then a third 905U module may be used to receive the message and re-transmit it. This module is referred to as a repeater.
Chapter Two Installation Where antennas are mounted on elevated masts, the masts should be effectively earthed to avoid lightning surges. For high lightning risk areas, surge suppression devices between the module and the antenna are recommended. If the antenna is not already shielded from lightning strike by an adjacent earthed structure, a lightning rod may be installed above the antenna to provide shielding. 2.2.1 Dipole and Collinear antennas.
905U-D Radio Modem User Manual horizontal and must be pointed exactly in the direction of transmission to benefit from the gain of the antenna. The Yagi antennas may be installed with the elements in a vertical plane (vertically polarised) or in a horizontal plane (horizontally polarised). For a two station installation, with both modules using Yagi antennas, horizontal polarisation is recommended.
Chapter Two Installation 2.3 Power Supply The 905U-D module is powered by a 10 - 30VDC or 13 – 24VAC supply. The power supply should be rated at 1 Amp and be CSA Certified Class 2. For DC supplies, the negative side of the supply is connected to "COM" and may be connected to “ground”. The supply negative is connected to the “GND” terminal internally. The positive side of the supply must not be connected to earth. The DC supply may be a floating supply or negatively grounded.
905U-D Radio Modem User Manual Example cable drawings for connection to a DTE host (a PC) or another DCE host (or modem) are detailed above.
Chapter Two Installation HOST 905U-D HOST RS485 CONNECTIONS HOST 905U-D HOST 120Ω DIP SWITCH FOR 120Ω SUPPLY RS485 RS232 - - 120 + + + RS485 CONNECTION USING TERMINATING RESISTOR Page 17 © January 2011
905U-D Radio Modem User Manual Chapter Three OPERATION 3.1 Power-up and Normal Operation When power is initially connected to the 905U-D module, the module will perform internal diagnostics to check its functions. The following table details the status of the indicating LEDs on the front panel under normal operating conditions.
Chapter Three Operation When the 905U-D unit detects data in the input buffer, it initiates a radio message. The radio message will end when the number of transmitted bytes reaches the maximum message length (configurable by the user), or if the input buffer becomes empty. If the configured serial data rate is the same or more than the radio data rate, then data is transmitted as soon as it enters the input buffer - data “streams” from the input buffer to the radio port.
905U-D Radio Modem 3.2.2 User Manual Serial Data Rate The communications baud rates supported on both the RS232 serial port and the RS485 serial port are 1200, 2400, 4800, 9600, 14400, 19200, 28800, 31250, 38400, 57600, 76800 and 115200 baud the user selects one of these rates during the configuration of the modem. 3.2.3 Radio Data Rate The data is transmitted by radio as direct modulated synchronous data at 19200, 57600 or 115200 bits/second.
Chapter Three Operation 3.3 Addressing A 905U-D network comprises modules with the same "system" address. Only modules with the same system address will communicate with each other. This feature allows more than one system to operate in the same area on the same radio channel. We recommend that you select a random number for the system address. In transparent mode, each module is also configured with a “group” address. A system may comprise several groups or sub-systems.
905U-D Radio Modem lead-in User Manual system/group addr data error check (if configured) |---------------|-----------------|------------------------------------------|--------------| 30msec 2 bytes 1 ms @19.2Kb 0.5ms per byte @ 19.2Kb 2 bytes 1ms @ 19.2Kb If error checking is not configured at the receiving unit, data will start to be output approximately 1 msec after the system address has been received.
Chapter Three Operation Module S and T are configured with group address 1 (only one group address as it is not configured as a repeater). When S transmits a message, T and A will receive it and output the data. If module X can hear the message, it will not output it as module X is configured with group address 2. Repeater A will re-transmit the radio message, but on group address 2. Module S and T will receive the re-transmitted message, but will not output the message as the group address is now wrong.
905U-D Radio Modem User Manual To establish a link, the master will transmit a special “connect” message. This initial message will not include any data. If the “slave” unit receives the initial message, and is not already connected to another 905U-D unit, it will return an acknowledgment message. Both units will activate their DCD LED, and also activate their DCD signal. If the master unit does not receive the acknowledgment, the DCD output will reset.
Chapter Three Operation Successful Communications Source Module • • • • • Destination Module Serial data is received Serial RX LED flashes Listen to ensure channel is clear If clear, transmit message Radio TX LED flashes --------> <-------• Radio RX LED flashes • Acknowledgment received okay - communication complete Unsuccessful Communications Source Module • Listen to ensure channel is clear • If clear, transmit message • TX LED flashes • • • • • Receive message Radio RX LED flashes Check system an
905U-D Radio Modem User Manual There is a special configuration of controlled mode which provides a 5msec lead-in time for fast operation (see below). With the fast operation, the time to transmit 20 bytes at 19200 baud is less than 20 msec. There are several configurations for controlled mode: 3.6.1 Auto-Connect Controlled Mode Auto-connect mode is similar to “fixed line” modem operation. The master unit wants to connect to only one slave address. Normally the slave address is preconfigured.
Chapter Three Operation Up to five repeater addresses may be configured as part of the remote address. That is, up to 5 intermediate modules can act as repeaters between the master and slave modules. The RS232 DTR signal can be configured to act as a disconnect signal. If so configured, the DTR signal will force a hang-up (DCD reset) if the host device resets the DTR signal. 3.6.4 Fast Operation Controlled Mode This configuration does not allow the use of repeater addresses.
905U-D Radio Modem User Manual Repeater Communications Successful Unit A Unit B Unit C Unit D Source Repeater Repeater Destination • Transmit message ---> • Receive message • Re-transmit message ---> • Receive message • Re-transmit message • Receive ACK • Re-transmit ACK Receive ACK <--- • Receive ACK • Re-transmit ACK <--- ---> <--- • Receive message • Transmit ACK • Output data Repeater units may also act as destination addresses for some transmissions and output
Chapter Three Operation We recommend that units in the same system have the same error-check configuration, however it is possible for users to configure the units differently. If a unit without error-check configured receives a message which includes an error-check, then the unit will treat the additional two bytes as data and output them to the host device.
905U-D Radio Modem User Manual same channel is small, and if this does occur, the probability of sharing the same channel on a re-transmission is extremely small. There is a higher chance of interference from other 905U-D systems. Because 905U-D are designed to operate in a peer-to-peer network, without a “master module” directing the communications, each 905U-D will scan the radio band looking for other 905U-D messages.
Chapter Three Operation If a system gives poor performance after it is installed, check the adequacy of the radio path refer to the Diagnostics Section 6. Interference will only cause a problem if the amplitude of the interference is comparable to the radio signal from the 905U-D units. If the interference level is relatively small, then it will not affect the performance of the system.
905U-D Radio Modem Chapter Four User Manual CONFIGURATION 4.1 Before Configuring Configuration comprises selecting parameter values for the operation of the 905U-D unit. Four pre-set configurations may be achieved using the four DIP switches. These configurations cover most applications - refer section 4.7. Before you start configuration, parameter settings must be decided. The main parameters are:• Addressing - system address, group address, unit address. • Character type.
Chapter Four 4.2 Configuration Addressing A 905U-D network comprises modules with the same "system" address. The system address is a 8 bit value (values 0 to 255). Only modules with the same system address will communicate with each other. If you are adding another module to an existing system, use the same value as the existing modules. If you are starting a new system, select random values and use the same value for each module. In transparent mode, a group address also needs to be configured.
905U-D Radio Modem User Manual Reading and Configuring a module You will need a connection cable between the PC and the 905U-D. The cable should have straightthrough connections as per section 2.4.1 of this manual. If your PC only has USB serial connections with no RS232 port, you will need to purchase a USB to RS232 converter cable. Select the communications port that you will be using on the PC - make sure that no other program is using this com port.
Chapter Four Configuration Modifying an existing configuration If you read a configuration from a module or a saved file, the program will display the configuration parameters. You can change these parameters, and then program the module and/or save the file. 4.4.1 Transparent Mode The default setting of the program is transparent mode.
905U-D Radio Modem User Manual This should be a unique address for that module (1 – 127). Auto-Connect Master In auto-connect mode, the “master” will automatically attempt to connect to the slave address. Once connected, the link can transfer data in either direction, with error-checking, acknowledgement messages, and automatic re-transmissions if necessary. If the link connection fails (indicated by the DCD led), then the master unit will automatically try to reconnect to the slave.
Chapter Four Configuration however it can also be used for single-connect. In fast operation mode, the master and slave modules continually communicate with each other (even if there is no data) to minimize radio synchronizing time when data is to be transmitted. You cannot use repeaters when using the option. Unit address should be less than 15.
905U-D Radio Modem 4.4.3 User Manual Other Parameters Radio Data Rate Select the radio data rate which you want to use. Note that modules will only communicate with each other if they have the same radio data rate. If you select a rate which is faster than the serial rate, the 905U-D will automatically set transmission delay parameters in registers S18 and S19 (refer section 3.8). To disable this, deselect the “PLC Mode” box in the Serial configuration window.
Chapter Four Configuration The number of Data Bits can be selected as 7 or 8. The number of stop bits can be 1 or 2. Parity can be none, even or odd. Flow Control “Flow control” affects the use of the CTS and RTS signals on the RS232 port. These signals can be used to prevent overflow of the input buffer or output buffer of the 905U-D. The settings should be selected to match the host device.
905U-D Radio Modem User Manual “Always On” - the 905U-D sets the DCD to be always on “Only High When Connected” - the DCD signal will be on when the link is connected and off when the link is reset “Pulse Low on Disconnect” - the DCD signal will be normally on but will switch off momentarily (for 0.1 sec) when the link is reset. Advanced Settings These settings may be adjusted if the host device is using AT commands - refer to Appendix A for an explanation of the different parameters.
Chapter Four Configuration Response from 905U-D OK Save configuration AT&W Exit command mode ATO Note that some commands will automatically exit command mode. Several commands can be run together, for example, ATB2&WO is the same as ATB2 and AT&W and ATO Prior to Configuration Before configuring a module initially, force the module to its factory default configuration either by using the DIP switches (refer section 4.3), or by using the AT&F command.
905U-D Radio Modem User Manual For example, AT&B9 will be 7 data bits, 2 stop bits, odd parity. The character type does not need to be the same for all modules in a system. Transparent mode If you have forced the module to factory default configuration, this configuration will not be necessary. The following commands can be used to change the configuration to transparent mode.
Chapter Four Configuration The module starts up in command mode and waits for a command from the host device. An ATD command will initiate a connect command to another module. HOS T 905U-D #5 905U-D #8 HOS T For example, ATD8 to module #5 will initiate a connect command to be sent to module #8. Module #5 will respond with RINGING to its host. If #8 is not already connected to another module, it will connect (set DCD) and respond to #5.
905U-D Radio Modem User Manual Controlled Mode Link Check and Reset times If the master module has not sent or received a radio message within a preset time, it will send a check message to make sure that the link is still active. If it does not receive a response from the slave unit, it will disconnect the link and reset DCD. The check time can be configured using the ATS6 command. For example, ATS6=10 sets the check time to 10 sec.
Chapter Four Configuration &V10 Display the Stored / Non-volatile Configuration. &V11 Display the elements of the stored configuration which differ from factory default. The 905U-D has two sets of configuration parameters - a set stored in non-volatile memory and an active set in RAM memory. Normally on start-up, the configuration is read from the stored memory to the active memory. Changes can be made on-line to the active configuration which are not stored.
905U-D Radio Modem Set the serial data rate to 38400 User Manual ATC6 Set the radio data rate to 19200 Set the character type to 7,1,2,even not necessary (default) AT&B13 Exit and save the configuration AT&W ATO The operating mode will already be in transparent mode from the factory default settings. The other default values for the other parameters will likely be OK.
Chapter Four Configuration Controlled Mode Source Repeater Repeater Destination #1 ----------------> #2 -----------------> #100 --------------------> #3 #101 Apart from being a repeater in the 1 - 3 link, 100 is also in a separate link to 101 Auto-connect link with repeaters Assume that default settings are used for data rates and character types. The only configuration required is addressing.
905U-D Radio Modem User Manual Exit and save the configuration ATO AT&W Module #100 Note that #100 is the master unit for a link between #100 and #101, It is also acting as repeater in the #1 to #3 link. The system address for #100 and #101 must be the same as the other modules so that #100 can act as a repeater.
Chapter Four Configuration Switch Function 0000 Normal Operation – no change 0100 Restore Factory Defaults. Equivalent Hayes Command at start-up. AT&F Baud rates 1100 Perform Transmit BER Test AT&T0 (for use with AT&T1 at other module - see section 6.2.1) Serial Radio 0010 Transparent Mode. AT&M0B0C4&L1 9600 19200 1010 “ AT&M0B1C6&L1 19200 57600 0110 “ AT&M0B1C9&L1 38400 57600 1110 “ AT&M0B2C10&L1 57600 115200 0001 Fast Controlled Mode, Autoconnect master.
905U-D Radio Modem User Manual Chapter Five SPECIFICATIONS General EMC specification FCC Part 15 EN 300 683 89/336/EEC AS 3548 Radio specification Housing FCC Part 15.427 902 – 928MHz, 1W AS 4268.2 915 – 928MHz, 1W RFS29 NZ 920 – 928MHz, 1W 110 x 185 x 30mm Powder-coated, extruded aluminium DIN rail mount Terminal blocks Removable Suitable for 12 gauge (2.
Chapter Five Specifications Expected line-of-sight range Antenna Connector USA / Canada 20+ miles Australia / NZ 20+ km Range based on 19200 baud. At 57600 baud, expected range is 60%, at 115200 baud, expected range is 30%. depending on local conditions Range may be extended using intermediate modules as repeaters Female SMA coaxial Serial Ports RS232 Port DB9 female DCE RTS/CTS/DTR/DCD hardware signals provided RS485 Port 2 pin terminal block Max distance 4000’ / 1.
905U-D Radio Modem User Manual Chapter Six TROUBLESHOOTING 6.
Chapter Six Troubleshooting &T2 Transmit & Receive BER Test. Used with a second module configured as a transparent repeater. &T3 RSSI Measurement. Monitors the received signal strength, and displays in dBm. Most radio tests are carried out using the AT&T2 test as this is the easiest to accomplish. AT&T3 - Received Signal Strength Display This option provides for testing the radio path between two 905U-D units.
905U-D Radio Modem Test 109 Errors 0 User Manual Extra 0 Level TotErr -77dBm 3 TotMissed 0 TotTest 109 kbit Test - the sequence number of the last received frame Errors - the number of bit errors in the last received frame Extra - any extra characters at the end of the frame (negative numbers indicate frame dropped out early) Level - the RSSI level when the frame was received. TotErr - The total errors received during this test.
Appendix A Hayes Commands Appendix A Hayes Commands The following details all of the Hayes commands supported by the 905U-D. Default settings are shown by a “dot”, • Command Function ATA Answer Incoming Connection message in controlled mode – the module can also be set to answer incoming connections immediately or after a certain number of attempts (see S-Register S0) - the default for S0 is 1, meaning that the module will normally automatically answer on the first connection attempt.
905U-D Radio Modem User Manual ATSn? Read value from S-Register n, see description of S registers later in this section ATSn=xx Set value of S-Register n to xx ATV Verbal/Numeric Response Codes V0 Numeric response codes V1• Verbose response codes ATX Extended Response Codes. Allows more detailed response codes, including connection speed.
Appendix A Hayes Commands &E1 Enable CRC Error Checking AT&F Restore Factory Defaults. This function is also available from the DIP Switches. AT&G Set module’s Group Address Range 0-255. Default 0. AT&K Flow Control Configuration. &K0 Flow Control Disabled. CTS Always high. Module ignores RTS. &K1 not used &K2 not used &K3 CTS/RTS Flow Control. CTS Reflects the state of the local buffer. Module only transmits serial data when RTS is high. &K4• RS-485 Control.
905U-D Radio Modem &N1• User Manual If a key is hit or a character input while attempting to connect, abort the connection attempt and return to command mode. AT&S Set module’s System Address Range 0-255. AT&T Self Tests. Allows in-field diagnostics, and factory testing. &T0 Transmit Bit Error Rate Test. Generates pseudo random data and sends out radio. &T1 Receive Bit Error Rate Test. Receives data from &T0 module, and records BER statistics. &T2 Transmit & Receive BER Test.
Appendix A Hayes Commands (ASCII code) S3 0-127 Carriage Return Character Normally 13 = S4 0-127 Line Feed Character Normally 10 = S5 0-127 Back Space Character Normally 8 = S6 0-255 Link Check Timer Units Seconds. 0 disables. How frequently to send a “Link Check” message. Usually set less than the timeout set by the AT\Tcommand. Default 0. S7 1-255 Number of Connection attempts How many times to attempt a connection after an ATD command. Default 5.
905U-D Radio Modem User Manual S16 0-255 Transmit Hold-off Time In msec (default = 0) S17 0-255 Receive Hold-off Time In msec (default = 0) S18 0-255 Input buffer delay Radio will not transmit until the number of characters in the input buffer = 2 x S18 value - see below S19 0-255 Input buffer delay override Override time in msec to override S18 delay - see below.
Appendix A Hayes Commands Response Codes Response codes display the status of the module in response to user commands. The response code displayed depends on the ATV setting, the ATX setting and the ATQ setting. ATV0 selects numeric response codes. ATV1 selects verbal response codes. The ATXn command selects extended response codes. ATQ0 disables all response messages. ATQ1 enables response messages. The following table describes the messages.
