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LAWNII Users Manual - East Bay Radio Controllers

1. 4 8 5 Chapter 24 Making RS 232 Cables for LAWNII Plus 77 Chapter 25 485 Option LAWNII Plus with 485 option The pins of the circular connectors are different when the 485 option is installed The pin out for the LAWNII Plus with the 485 option is as follows Pin Description In In Out Out Gnd NC NC NC Vcc 8V input OON AU BWHN gt gt OCI supports the 485 option by installing a special version of firmware that enables the Push To Talk function to the CTS output at the serial port This CTS signal is used as the transmitter enable for the 485 port driver Both the input and output pins of the 485 ports are not terminated so that an external termination resistor will be needed if it is required 485 Option for the regular LAWNII For the regular LAWNII model the 485 option is available with a plug in 232 485 converter module outside the unit This 232 485 convert is designed specifically to convert the RS 232 port of the LAWNII to an RS 485 port The termination resistors for the 485 port are included in the converter module They can be activated by simply applying a drop of solder to bridge the connecting pads The bias resisters for the RS 485 data bus are also included These bias resistors set the quiet bus voltage to 2 5V for optimal noise immunity These resistors can be activated by the
2. sssese 23 Changing the LAWNII Serial Settings neueren deren enini nnns 23 Checking LAW NII SEO S iii O EE RO UO ne Reli dE ac uerius 23 Using the TemmialEmuletot s a dietro eite a ita 24 USING tme LOOM back Test aaa oa 24 USING the LAWN Wiza A i seti nomeo ia a 25 Chapter 3 Oveirvie We cnica ava qu Ts A CE OKGR YEA Un RU du Gu Ux E ERR Gv uiv ww V VE YRT aii 26 Chapter 4 Operation Modes vuicxccncainoainacianananconias cuaUa duos eEUVxx CERRO vae ad Vasa ids sudor nnana 27 COMMANA Modena ss 27 Man nparent Mod e 28 Retum to command mode from transparent mode seen 28 Penpheral device Mode contadas 28 Default Contriec topelfdtioi i eco odia 29 Datagram Mode dieis EE 29 Chapter 5 Operation requirements ss sssssssnnnsssnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn nnmnnn nnna 30 Na ME errun 30 SS Mm NUM E e 30 A 30 Radio chac aos 31 Hardware testi A 31 pe 232 Interface ie ropes art SPP TOR m been adt Sar RS SER ET OR RO ER PEON AA 31 Chapter 6 Commands the User Can Modify mcccococnccccconnanccconananoconanannncrnnnanaranannanerzznaaa 32 AA AS RS RES DA SEARS 32 AUTOLE SN ORB arar adria doses dedo aud de esas as 32 AWGEN SS A AS Eade ah ay 32 BEACON EVERY N BEACON AFTER N a ooa TB ERR Scd caes s 32 BREA AS EE IES ARO quida 33 BREAKDN T e a dead od da dv as 33 CHEN 10 9 8 84 E A Seno Oe See ds See
3. Description of the Rear Panel of the LAWNII Above The rear panel of the LAWNII 1 Reset A momentary push button that causes the LAWNII to return to the power up reset condition 2 RS 232 Data A female 25 pin RS 232 connector 3 Power Accepting AC 10V or DC 12V input Depends upon the models Chapter 1 Rules and Descriptions 17 Installing the OEM board The OEM board can be mounted in two ways either with the radio board on top or the processor board on top The advantage to mount the radio on top of the processor board is that it will reduce the chance of damaging the component during assembly and it will also allow more room when screwing the SMA connector of the cable to the board However it will be difficult to check the status LEDs since they will be at the bottom If the processor board is installed on top of the radio board there is a chance that the production operator might damage the components during assembly especially when power tools are used The components of the processor board are not shielded and the components can be damaged by force if something hard like a tool hits the components by accident In contrast the radio board is completely shielded and no components are exposed As a result it is safer to handle the boards from this side during assembly You must also allow some room for the connectors There are three connectors on the board an SMA connector for the antennas a DB9 for the
4. Performance Improvement by Parallel Repeating The performance improvement by multiple transmission with parallel repeaters can be calculated as follows Omnispread Communications Inc 86 Suppose the success rate of transmission is p then the packet will have a failure probability of 1 p For example the success rate is 90 then 10 will be lost or the failure rate will be 0 1 If the message is sent twice then the chance that both packets are failed is equal to 1 p Using the same success rate of 90 then the failure rate will be 0 01 which is 1 The failure rate can be less than 0 1 with triple transmission From these numbers the success rate is greatly improved by multiple transmission However the system must ignore multiple request and send out only one response per request to minimize the collision Chapter 26 Using Repeaters for the Broadcast Mode 87
5. Property Option and dick the Settings Click the Terminal for the Function arrow and Ctrl key act as Click the VT100 for the terminal type Click the Configure option to select the right serial port specs which is 9600 N 8 1 for a new LAWNII from the factory Now the Windows 95 will work like a terminal After setting up the terminal you should exit the hyperterminal and reboot the computer before using the Hyperterminal to talk to LAWN II Some computer will not change the serial port set tings without doing so especially if the default serial setting of the computer is not 9600 N 8 1 Using LAWNII Configuration Program 3 0 with Terminal Emulator The LAWNII Configuration Program 3 0 is a Windows based configuration program designed for Windows 95 98 98 SE and 2000 Professional to help customers configure the LAWNII in a familiar graphical user interface system The program eases the configuration of the LAWNII by handling most of the routine commands with an easy to use graphical interface Version 3 0 is an improved version of version 2 1 with a faster communications setting search supporti for the new LAWNII firmware and a new loop back test function Version 3 0 retains many of the powerful features of version 2 1 such as the terminal emulator which automatically switches the settings of the local communications port as the LAWNII s com munications port settings are changed This eases the programmi
6. Before you start you need to remove the plastic backing of the tape A sharp object like a utility knife can greatly help you pick up a corner of the plastic backing so that you can peel it off easily The proper way to apply the cold shrink tape is to start from about 1 below the end of the heat shrink tape on the cable s connector and winding the cold shrink tape upward until the connector is covered and them downward until the tape is used up Every new layer of the tape must cover at least 50 over the previous layer You must also stretch the tape so that the width of the tape is reduced by 30 when winding the tape The tape will be fused together under the tension and form a permanent protection for the connector Please also visually inspect the cable to make sure that the black PVC cover of the cable is not Chapter 22 Installing the LAWNII Plus System 69 punctured or cut through The PVC must be free from holes and cuts that can let the moisture get inside the cable and connector and cause problems in the future If there are holes and cuts you must use some sealing tape to fix them Please also prevent from pulling the cable too hard The connectors on the cable are either crimped or clamped to the cable Excessive pulling force can damage the connector s connection permanently Please use some cable ties cables clamps or tape to secure the cable run so that the long cable itself will not become a load for the connectors
7. FORMANCE OF THE PRODUCTS ARE ASSUMED BY YOU IF THE PRODUCTS ARE DEFEC TIVE OTHER THAN AS SPECIFICALLY WARRANTED ABOVE YOU AND NOT OCI OR ITS DEALERS DISTRIBUTORS AGENTS OR EMPLOYEES ASSUME ALL LIABILITY AND EX PENSE INCURRED AS A RESULT THEREOF IN NO EVENT WILL OCI OR ANYONE ELSE INVOLVED IN THE CREATION PRODUCTION OR DELIVERY OF THE PRODUCTS BE LIABLE FOR ANY DIRECT INDIRECT SPECIAL INCI DENTAL OR CONSEQUENTIAL DAMAGES INCLUDING BUT NOT LIMITED TO DAMAGES FOR LOSS OF PROFITS INTERRUPTION OF USE LOSS OF DATA ARISING OUT OF THE USE OR INABILITY TO USE THE PRODUCTS EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGES Some states don t allow the exclusion or limitation of implied warranties or limitation of liability for incidental or consequential damages so the above limitation or exclusion may not apply to you Foreword Xi Chapter 1 Rules and Descriptions Description of the Bottom Panel of the LAWNII Plus Q T Transmit Q C Connected Q R Received Q P Power Above RS 232 Circular Connector P Power A red LED that indicates the LAWNII Plus is powered up R Received A red LED that indicates the presence of radio carriers It is also called the Traffic LED in some occasions C Connected A red LED that indicates the LAWNII Plus is virtually connected to its destination and it is not available to other LAWNII Plus s T ransmit A red LED that indicates the LAWNII Plus
8. No acknowledg ment is required and no retry is attempted The Datagram mode is only available for LAWNIIs operated in the transparent mode Only unconnected packets are monitored by a Datagram LAWNII This prevents the Datagram LAWNIIs from monitoring other LAWNII s traffic The Datagram mode is enabled by the UNPROTO LCALLS LAWNGRAM and TRANSGRA commands The Datagram mode is designed to replace RS 485 multidrop net work The user must have a polling software with error detection and resend mechanism to ensure the data integrity Chapter 4 Operation Modes 29 Chapter 5 Operation requirements Name The name as defined by the MYCALL command consists of up to 6 characters Each LAWNII needs to have an unique name except when they are used in the Datagram mode The name may be extended with a I to 9 Names may include all alphanumeric characters and other char acters including 1 lt gt Examples of valid names are STEVE 3 JOHN JOSEPH 9 MASTER SLAVE Each packet sent from one LAWNII to another has both the source name and the destination name in it Please be advised not to use 1 suffix for your LAWNII The 1 suffix is reserved for a LAWNII used with a printer that is operated differently than a standard LAWNII System number A number between 0 to 32672 Is included in the address of every packet Both the system num ber and destination name must match for a LAWNII to accept the packet
9. Peripheral device mode If the MYCALL name and the DFCNAME name are the same then the LAWNII is assumed to be driving a printer or something similar and is in the peripheral mode The peripheral mode makes the LAWNII as transparent as possible to the equipment it is attached to While in the peripheral mode the LAWNII does not return to the command mode after a discon nect The LAWNII can only be brought to the command mode by the wake up sequence The ASYNC break does not return the LAWNII to the command mode This prevents unintentional break conditions such as the power up or power down of the attached equipment from causing the LAWNII s to return from the peripheral mode to the command mode While in the peripheral Omnispread Communications Inc 28 mode a LAWNII will not send any messages to the connected peripheral such as the firmware s check sum revision and OCI trademark informations during the power up self check Default Connect operation If the LAWNII is not in a state of virtual connection and has the default connect mode DFC enabled then the LAWNII will initiate a connection to the destination LAWNII which is named by the DFCNAME command automatically when the data enters the serial port The data will then be sent after the virtual connection is established The LAWNIIs will remain connected until all the data are sent The virtual connection will be dropped when the serial port becomes quiet for some ti
10. as following MASTER RSLAVE MYC M1 SL1 DFCN M1 SL1 LCALL M1 SL1 UN SL1 M1 LAWNG ON ON TRANSG ON ON Parallel repeater set RMASTER M2 M2 M2 SL2 ON ON SLAVE SL2 SL2 SL2 M2 ON ON The parallel repeater set can increase the coverage area of your system by sending multiple broad cast messages The parallel repeater set system can be illustrated as follows 7 Above Master to slave path SW gt RMASTER Chapter 26 Using Repeaters for the Broadcast Mode 83 om Above Slave to master path Please note that there is no connection between the RMASTER and RSLAVE and the RXD and TXD of the RMASTER and RSLAVE are tied together so that the data will automatically rebroad casted as soon as it is received by RMASTER or RSLAVE You will need to program the radios as follows MASTER RMASTER RSLAVE SLAVE MYCALL M1 M2 S2 S1 DFCN M1 M2 S2 S1 LCALL M1 M2 M1 S1 S1 S2 UNPROTO S1 M2 S2 M1 LAWNG ON ON ON ON TRANSG ON ON ON ON By this way the MASTER will receive the packet addressed to either M1 or M2 The M1 packet will come from the SLAVE while the M2 packet is from RMASTER By the same token the SLAVE will receive the packet addressed to either S1 or S2 The S1 packet comes from the MASTER directly while the S2 packet comes from the RSLAVE When the MASTER broadcast a message to the SLAVE the message can be directly received by the SLAVE Since the RSLAVE can also receive the same da
11. communications Each of the flow control inbound or outbound software or hardware can be programmed inde pendently Chapter 11 Application Notes 47 Packet formation The packet formation determines how fast and how quickly the data is sent over the LAWNIIs The packet formation just like the baud rate of the two ends of a link needs not be the same The user should find out the system s requirement and uses the optimal packet size for the system For example for a scale that is constantly sending out 20 bytes of data to the indicators the packet size should be exactly 20 Or for a data collector that sends 5 bytes of data to the computer and receives 2 bytes of acknowledge from the computer should have 5 bytes as the packet size for the LAWNII with the data collector and 2 bytes for the LAWNII with the computer Please note that the packet size must be 1 for the LAWNII plus used with a terminal The packet size of 1 will ensure that the keystroke is sent to the computer as soon as the user hits the key board Timing When switching from the command mode to the transparent mode be aware that the switching may take up to 50 msec Since separate data queues are maintained for the command mode and the transparent mode the data could end up in the wrong queue if insufficient delay is inserted Conok off busy message When conok is off no LAWNII can connect to your LAWNII however each connect attempt by another LAWNII is
12. computer Each MHEARD command must be followed by aMHCLEAR com mand for this approach to function properly MHCLEAR Clears the MHEARD list in the LAWNII MYCALL name Default JPRNTR Sets a new name for the attached LAWNII The LAWNII will return its name if the MYCALL Chapter 6 Commands the User Can Modify 35 command is entered without a name For example MY STEVE will set the LAWNII to a new name STEVE MY will ask the LAWNII to return its name for example the LAWNII will return MYCALL IS STEVE PACLEN n Default O Sets the packet length used between LAWNII n can vary between 1 and 256 which is also represented by O Longer packets are more efficient in throughput for a busy network Shorter packets are more efficient in time and is more suitable for most real time system For example in a terminal network application an entry at the terminal usually requires immediate response from the terminal server to download a lot of data to the terminal So the LAWNII that is connected to the terminal should have a minimum packet size of 1 and the LAWNII that is connected to the terminal server should have a maximum packet size of 256 Please note that a packet has approximately 20 bytes of overhead and a packet also requires 20 bytes of keyup time for the transmitter as a result small packet size is not efficient to send data PACTIME AFTER N and PACTIME EVERY N Default After 10 EVERY sets PACTIME t
13. enter the terminal tab the LAWNII Configura tion Program will try to get the LAWNII into command mode and turn echo and automatic linefeed on for you so that it is ready to communicate with you The other unique feature that makes the LAWNII Configuration Program s terminal emulator so useful is that it handles the changes in the serial settings of the LAWNII automatically For example if the LAWNII is currently set to 9600 n 8 1 and you issue PARITY 1 odd parity to the LAWNII the LAWN Configura tion Program will send the new command to the LAWNII take note of this new change and it will change your local serial settings to the new settings after you issue the SAVE and RESTART commands If you issue AB 2400 to change the baud rate of the LAWNII the program will send the new baud rate command to the LAWNII and change the terminal s baud rate to the new settings so that you can continue to communicate with the LAWNII without any interruption Please remember to issue the SAVE command to store the new settings to the LAWNII It is your responsibility to do that The program will not do that automatically for you during the terminal mode Using the Loop back Test A new feature of the LAWNII Configuration Program is the Loop back test that allows you to test the RF link between two LAWNII s During the loop back test the unit being tested will connect to itself via a remote unit so that any character sent to unit under
14. follow the procedures as outlined in Chapter 2 Programming the LAWNII to set up the terminal to communicate with the LAWNII Plus You then follow the examples as in Chapter 4 Operation Modes to configure the LAWNII Plus into the operating mode you need After both LAWNII Plus are programmed you need to perform the connect test to make sure that the system settings are correct and also the loop back test or actual data test by using two termi nals to make sure that the interface settings are correct This test confirms that the two LAWNII Plus are in a good shape and are ready for installation Installation After the bench functional test now you are ready to install the LAWNII Plus system Plan your installation procedure carefully and completely before you start Successful installation is largely a matter of coordination and preparation You should first decide whether to install the radio indoor or outdoor with the antenna It is recommended that you install the radio indoor so that the status LED of the radio can give you an instant feedback when you are sending data or doing alignment or test Besides without the effect of the elements the radio s enclosure will last forever The radio itself is packaged in a weather proofed NEMA 4X enclosure and it can survive the outdoor environment Nevertheless the sealer around the cover will eventually give up over the years if the radio is exposed to the weather all the time If you need
15. from Windows 95 for instructions 2 If you are using LAWNII Plus plug the cable with the circular connector supplied by OCI to the LAWNII Plus and plug the power cube to the wall outlet and the DB9 plug to the terminal If you are using LAWN plug the male DB25 plug that is labeled LAWN to the LAWNII and plug the other end of the cable the is labeled as COMPUTER to the terminal There are two female plugs on this end a DB9 and a DB25 Please use only one of the plug Plug the power cube to the wall and the power plug to the LAWNII 3 The Power LED of the LAWNN should come ON immediately and the Connect and Transmit LEDs should blink once Please refer to Chapter One Rules and Descriptions for the locations of these LEDs This indicates that the LAWNII has passed the initial power up self check success fully 4 Type lt Ctrl gt C three times with one second of silence before and after the three lt Ctrl gt C to switch the radio to command mode For example wait one second without typing any key and then hold down the Ctrl key and quickly hit C key three times and let go both keys and wait for one second In the command mode LAWNII is not case sensitive It will convert all character inputs to upper case 5 Upon the receipt of three lt CtriC the LAWN should return a cmd to the terminal This indicates that the LAWNII has switched to the command mode successfully and is ready to accept more commands
16. from you Once the LAWNII is in the command mode you can start programming the LAWNII by following the examples in Chapter Ten Examples Once the LAWNI is programmed as the examples as a peripheral device in the transparent mode or in DFC mode it will be ready to send or receive data for you whenever it is powered up again You do not need to program it until you want to change the programming again 6 The command mode is the mode that you communicate with the LAW N s firmware For example you can change the name of the LAWNII the radio channel the system number the baud rate the parity or the word length etc Or you can configure the radio into the right operat ing mode for example into the master slave broadcast mode one to one DeFault Connect DFC or manual connect mode You can also perform some network functional tests for example to tell this LAW N to establish a Omnispread Communications Inc 20 virtual connection with the other radio directly or through repeaters or to disconnect an estab lished virtual connection If your radio is virtually connected to another radio these two radios will then work together like the two ends of a cable You can check the network status of the radio For example you can ask the radio how many retry occurred since the last restart If there are lots of retries the link could be weak or the air traffic could be too congested You can also ask the radio about the Heal
17. or any other obstruction of any kind between the two antennas The effec tive coverage range can be severely reduced if LOS is lost Normally the LAWN II Plus is mounted together with the antenna on the mast so that the cable loss is minimum If the range is short and a moderate cable loss is acceptable you may install the LAWN II Plus inside a building and run a low loss cable such as an RG 8 cable to connect it to the antenna You may purchase the cable from OCI or build it yourself Unless the cable run is short please do not use RG 58 cable To build the cable you will need to get a pair of N female and male connector and swap the contact pin and socket Please note that the reverse N connectors used by OCI are nonstandard Extra attention is required to make sure that your connector mate with the OCI s connectors without mechanical interference Improper mating could damage the connectors permanently It is strongly recommended that the customer buys at least one cable from OCI as the reference before making his own cable Antenna Height Requirement for long range applications more than 5 miles In order to maintain a LOS condition the antenna should be always mounted at the possible highest location such as a tower the roof of a tall building or mountain ridge Since the earth is round the higher the antenna is mounted the longer the LOS distance it can cover The following is a table showing the distance of horizon vs the antenn
18. same manner as the termination resistors In the half duplex mode the CTS signal from the 232 port is used as the transmit enable of the 485 output driver This control signal is generated automatically by the LAWNII s microcontroller so that the serial port is completely transparent to the user The converter can be powered directly from the LAWNII It can be also powered by an external power supply if it is used with other devices The interface to the 232 485 converter can be illustrated as follows Omnispread Communications Inc 78 pin 485 port Description 1 Vout 9Vdc output from the LAWNII 2 Gnd ground 3 O Positive output 4 O Negative output 5 Negative input 6 Positive input 7 Vin External power supply input 7 10V 8 Gnd ground pin 232 port Description 2 RXD Data to the LAWNII 3 TXD Data from the LAWNII 5 CTS Transmitter enable for half duplex mode 7 Gnd Ground 13 Vin 5V in from LAWNII 14 Vout 9V out from LAWNII connected directly to pin 1 of the 485 port OCI supports the 485 option by installing a special version of firmware that enables the Push To Talk function to the CTS output at the serial port This CTS signal is used as the transmitter enable for the 485 port driver The LAWNII with the 485 option is called LAWNII 485 model 200 485 You need to order this way so that it will come with the special firmware The normal firmware will not work with the 232 485 converter LAWNII
19. state is FRMR in progress This will occur if two or more LAWNIIs with the same name are used in a network and one of them has had a packet error Be careful about the use of LAWNIIs out of the box with the name JPRNTR already connected This message is received if you try to connect to LAWNII while another connection exists Other messages retry count exceeded This occurs if the destination LAWNII did not respond in RETRIES attempts A disconnect occurs lt name gt busy This appears if the destination LAWNII is busy This could be because it is connected to another LAWNII or because its CONOK is OFF Omnispread Communications Inc 42 Chapter 10 Examples The following examples show you how to use the LAWNII to send and receive data for your application The first two examples are for sending and receiving data manually and the last two examples are for most real world applications that using LAWNII to replace RS 232 and RS 485 cables Send data sequence Screen cmd MYC TEST cmd CONNECT STEVE ACES CAC cmd DISCONNECT Receive data sequence Screen cmd TRANSPARENT C C C cmd Loopback test Screen cmd MYC TEST cmd CO TEST VIA STEVE Comment name the LAWNII connect to destination called STEVE go to transparent mode put data here can be binary If STEVE is connected to a terminal the data should show up on the terminal get back to comman
20. test will be automatically echoed back right away through the remote unit Before you can start the loop back test you need to make sure that both units are programmed to use the same channel and system number You also need to know the name MYCalh of the remote unit It is usually a good practice to write the name of each unit on a yellow self stick note and affixe it on each unit so that you can easily identify the unit To start the loop back test you need to enter the name of the remote unit that you wish to test with Please note that if you have a multidrop network you must test each remote slave unit in the network one unit at a time All the other slaves that are not being tested must be turned off completely Omnispread Communications Inc 24 After entering the mycall name of the remote unit you can press the Start button and the LAWNII configuration program will establish a connection to itself via the remote unit and the connected LED of the unit under test will be ON Then the computer will continuously send The quick brown fox jumped over the lazy dogs back where represents the number of times the message has been sent to the unit under test The messages sent will be shown in the transmit box If you have a good RF path between the two test units you will see the same message arriving to the receive box quickly The LAWN configuration program will also calculate the data throughput for you Si
21. the name of IPRNTR and stay in the peripheral mode RESTART The RESTART command is the same as a power up or hardware reset RETRY n Default 15 Sets the number of retries to use when a packet fails to be received correctly SAVE This is a new command for the models that use EEPROM to keep the settings Without the SAVE command the new settings will not be stored into the EEPROM and be lost upon the removal of power the RESTART command or a hardware restart This command is not needed for the original LAWNII using battery as memory backup STATUS Returns a message with the number of packets left to be transmitted The zero value is the only reliable number and tells the user that all packets have been sent If no high level protocol is used between computers then a disconnect should not be issued until the status command returns O packets outstanding Otherwise data will be lost OCI s experience indicates that if STATUS is continuously requested packets remaining will not be transmitted Issue the STATUS command approximately every half second for proper opera tion Chapter 6 Commands the User Can Modify 437 SYSNUM n Default O Allows setting of system number which may be O through 65535 SYSNUM is preserved through RESTART a hardware reset or power on All units in the same system must have the same system number TIMEOUT n Default 15 Sets the time out for the default connections If there is no actio
22. used with LAWNII which is a DCE device If you are using the converter with a DTE device such as computer terminal or printer you will need to cross the pin 2 and pin 3 on the RS 232 port D The converter can be powered by an external power supply The input voltage range can be from 7 to 12 V The current consumption is about 30 mA Chapter 25 485 Option 81 Chapter 26 Using Repeaters for the Broadcast Mode There are two ways to implement the repeater set for a multidrop broadcast network One way is to extend the coverage distance by using the serial repeater set and the other way is to gain the coverage area by using the parallel repeater set You may choose either way that best suitable for your application The indoor coverage distance of the LAWN system is normally up to 300 The distance might be less if there is severe multipath signals in your building The typical symptom of multipath is that the link becomes sporadic and it goes from good communications to bad and from bad to good communications without apparent reason This problem becomes more severe especially at the limit of the coverage range The only way to reduce the impact of multipath is either to strengthen the link by reducing the coverage distance or to do multiple broadcast so that the probability of getting the data through is improved If you choose to strength the link you need to implement the serial repeater set If your system is mobile you probably
23. 32 port are commands which are not sent to the air The user can change the settings and operation of the LAWNII by sending new commands to it Or the user can ask the status of firmware by issuing commands For example the user can find out how many other LAWNII are active in the area by sending the MHeard command The LAWNII will return a list of the users that recently sent packets to the air Or if the user would like to find out the robustness of a connected link he can issue a RESend 0 command to dear the resend counter before sending the data At the end of transmission he can issue a RESend command to see how many resends had occurred during the transmission This will indicate how robust the link is The command mode can be activated whenever the user needs to communicate with the firm ware In the transparent mode all the input and output of the serial port either data to be sent to the air or data received from the air are data This is the normal operating mode for data communica tions Command mode The command mode is the normal mode for communication between the user and the LAWNII s firmware The command mode is noted by the presence of the cmd prompt from the LAWNII after it receives a command The normal operation for the command mode is for the user to send a command to the LAWNII the LAWNII will return the prior state for that command and then the LAWNII will execute the command and return a
24. Ds Ground 5 6 DSR i 6 Jesse BIS eee 7 8 CTS e 8 Dista Power 9 Power Connector Chapter 15 Description of the Circular Connector on the LAWNII Plus 53 Chapter 16 LAWNII Plus Specifications Interface RS 232 Serial port Flow Control software amp hardware RF Channels 3 Transmit Power 13dbm max Sensitivity 97dbm typ 94dbm typ for OEM model Frequency channel 1 90745 MHz channel 2 914 81 MHz channel 3 921 10 MHz Modulation FSK spread spectrum Antenna one external No of chip per bit 16 Bit rate raw 76 8 Kb sec Throughput 38 4 Kb sec Protocol AX 25 Contention CSMA CD Range 300 feet typical indoors w monopole antenna For outdoor unobstructed point to point applications and using same antenna on both ends 0 8 mile typical w unity gain antenna 1 6 miles typical w 3 db gain antenna 3 2 miles typical w 6 db gain antenna 6 4 mile typical w 9 db gain antenna 12 8 mile typical w 12 db gain antenna 14 miles typical w 13 db gain antenna Dimension 4 5 x3 5 x2 5 LxWxH Omnispread Communications Inc 54 Chapter 17 Installation of the LAWNII Plus Introduction to LAWN II Plus installation LAWN II Plus is operated in the 915Mhz band which requires a Line Of Sight LOS condition for a reliable communications just like radars The LOS restriction means that there should be no tree no truck no building
25. Pike C6 P O Box 248 Spring House PA 19477 Type of Equipment Wireless RS 232 Radio Modem Model Number LAWNII Plus OEM model 211 Year of Manufacture September 10 1998 the undersigned hereby declare that the equipment specified above conforms to the above standard Wen T Lin President Omnispread Communications Inc Test Facility Washington Laboratories Ltd 7560 Lindbergh Dr Gaithersburg MD 20879 NVLAP 200066 0 Omnispread Communications Inc viii LAWNII Users Manual For Model Name LAWNII Plus LAWNII Plus OEM and LAWNII FCC ID LTALAWNII LTALAWNIIP LTALAWNIIPO This device complies with Part 15 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 WARNING It is the responsibility of the installer to ensure that this device is properly installed to comply with the FCC adopted Radio frequency exposure limits The 12 and 13 db Yagi antennas should be mounted with minimal separation distance of 7 5 cm from all persons in order to avoid RF expo sures that may exceed the allowed limits All Yagi antennas should be mounted with their main beam away from any persons Foreword ix Notices Omnispread Communications Inc OCI has written this manual for use by OCI customers The information conta
26. Plus OEM board with the 485 option Since a DB9 connector is used for the LAWNII Plus OEM board the 232 485 converter which has a DB25 plug for the RS 232 port can t be directly plug into the OEM board Instead a special cable is needed to solve the interfacing problem You need to order this special cable along with the converter to convert the OEM board to 485 option Chapter 25 485 Option 79 422 option The 232 485 converter can be changed to a 232 422 converter easily To change the mode of operation the user needs to open the cover of the converter and set the dip switch to the proper settings The dip switch for the mode selection is illustrated as follows for the 485 option please choose the settings for half duplex and for the 422 option please use the full duplex settings 485 Port RS 232 Port Half Duplex 1 20N 3 4 OFF Full Duplex 1 2 OFF 3 4 ON Termination and Bias The termination resistors for the 485 port are included inside the converter These resistors how ever are normally not connected to the 485 port until they are needed and activated by the user Please refer to the following diagram for the locations of the activation pads Applying a drop of solder to bridge the pads of out and in will connect a 120 ohm resistor to the output and input of the 485 port respectively 485 Port RS 232 Port Solder Side View Omnispread Communications Inc 80 In the Half duplex mode the bus is no
27. R LIFE Site Selection Before attempting to install your mast think where can you place your mast for safety and best performance To determine a safe distance from wires power lines and trees 1 Measure the height of the mast 2 Add this height to the height of your tower if any and then 3 Double this total for the minimum recommended safe distance If you are unable to maintain this safe distance STOP AND GET PROFESSIONAL HELP Do Not Install Here 4 Chapter 17 Installation of the LAWNII Plus 57 Suppose the power line is 50 from the mast then the mast must be shorter than 25 If the mast is mounted on a chimney you must deduct the height of chimney that is above the roof top For example if the mast is mounted on a chimney that is 10 above the roof The mast then must be shorter than 25 10 15 15 to maintain a safe distance from the power line Generally speaking the higher the antenna the better it performs However please bear in mind the FCC limits your antenna height to 60 feet The following two diagrams show you how to choose a better antenna location when you install the antenna on the roof The Yagi antenna is directional and the front to back ratio is usually greater than 10 In other words the antenna receives most of its signal from the front along the wave guiding ribs than from the back So a good location for the antenna must 1 have no metallic object near the front The meta
28. RUM ONES E TRE qoos cae d AAA ES o 39 OE yal rs DT rae aa td suus a at is S 3 9 TRANSGRA AONO ORB pirado bebes be p Sb De Ve mud arty d fa Se 39 UNERQGTO names penega e ue RU LUCR SUUS RULES ats DE a ae AI ite NULLI US 39 Chapter 8 485 Option Command ee anne OD NS ies erasa a a aie quta ien qua c ata Rao S Roca ddr epa ee he Seta UR E 39 Chapter 9 Messages from the LAWNII ee eeeeee nennen nennen AO Command mode MESSAGES cooocccccncnoccccnnonononnncnnonannnnnnonononnnnoncon nnne naar nne EEEn EEEE 40 Command mode eror messages ssssssssseeeeeeeeen nnne nennen nennen nnns 40 Link status Me SSA GOS nada adidas 41 OMeniMessa Ges mer 42 Chapter 10 Examples science nina RARA aabt 43 Seriddata SEQUE AC E A any cab Ai 43 Receive data sequence acidi oe a a 43 Herr dicic A dali iia ev nal eda ise Aart ieee ey 43 Master lave NEW Kosta aa 44 RS 232 cable replacing ONe tO 0N8 ccccconnnccooonononnnnncnonononanononnnonnnnnnnnnnonanan no nnnnnnnnnos 46 Chapter 11 Application Note ssssnnusnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn nnmnnn nanna 47 Radio propagation investigation oonooccccnnnnncccncnonnoannnccnonnonononnan nro nnnnnnr rn nnne 47 Using repeater set to extend coverage range in the broadcast mode 47 EM COMO ati 47 Packet Tormmaliony a cd Eo 48 A temet UNT I 48 Conok off busy mesage anda 48 A cio aM A E E E E AA E 48 Data
29. S2 Y Abvoe Master to slave path Chapter 26 Using Repeaters for the Broadcast Mode 85 A Above Slave to master path The parallel repeater set can be used as many as needed until the air traffic is too congested and cause collision problems This problem is caused by two radios trying to transmit the signal at the same time and unfortunately one or both of the signals will be lost when it happens In order to reduce the possibility of packet collision you must reduce the number of transmission as much as possible One way to achieve that in a parallel repeater set is to hold the MASTER and SLAVE unit from responding too quickly For example in the above system with two repeater sets the SLAVE will receive a total of 3 requests from the MASTER unit Supposed it take 100 msec for the SLAVE to receive the packet from the MASTER directly then it will take 200msec from the first repeater set and 300msec from the second repeater set To minimize the possibility of collision the SLAVE should not respond right away when it receives the direct packet from the MASTER instead it should wait for 200 or more msec to make sure that all the repeaters should have been off the air and then return the response to the MASTER The SLAVE may or may not receive all the packets from the repeater set but as long as it waits for a another 200 msec after receiving a good packet before returning a response the probability of collision will be greatly reduced
30. Table of Contents a A ENEE v Declaration Of GOnDnfo ty ud a vi Declaration OT C OMPONTILY a dns viii WARNING Oda ix DUOC er x UMEO WARRANT cance Ea eduardo ant ect esc dedo ub poda ar senden xi Chapter 1 Rules and Descriptions eee ner 12 Description of the Bottom Panel of the LAWNII Plus eene 12 Description of the Top Panel of the LAWNII Plus eeeeeennnnnnn 13 Description of the Interface Connectors of the LAWNII Plus OEM Board 14 Installation of LAWNII Plus OEM itai dida 15 Description of the Front Panel of the LAWNII eeeeeeeeennnnnnnn 16 Description of the Rear Panel of the LAWNII sese 17 Installing the OEM DO al it 18 FCC Rules for Customers Using LAWN II Plus OEM Board eeeeeeee 19 Chapter 2 Programming the LAWN ll oonnnccccooccnccccconnancconnnnnncccnnnnnnrnnnnnnn one nnnm nnn 20 Using a Terminal or MS DOS Terminal Simulator esee 20 Using the Terminal Simulation Program from Windows 3 1 seeees 21 Using the Terminal Simulation Program from Windows 95 esee 22 Using LAWNII Configuration Program 3 0 with Terminal Emulator 22 Installing the LAWNII 3 0 Configuration Program eere 23 Getting Started with the LAWNII Configuration Program 3 0
31. The RF cable is a very important part of the signal path Please handle the cable with care Installation Tips and Warnings When installing the system remember do not use a metal ladder Do not work on a wet or windy day Do dress properly shoes with rubber soles and heels rubber gloves long sleeve shirt or jacket If the antenna or other parts start to drop get away from it and let it fall Remember the antenna mast guy wires and cable are all conductors for electricity current Even a slightest touch on any of these parts to a power line can kill you If any part of the system should come in contact with a power line DO NOT TOUCH IT OR TRY TO REMOVE IT YOURSELF Call your local power company They know how to do that safely Before you climb up the ladder to install the LAWNII Plus system you should assemble the system on the ground of the installation site First clamp the antenna to the mast then use the adjustable clamp to mount the radio right under the antenna if you need to install the radio outdoor with the antenna The radio should be mounted with the metallic antenna connector pointing to antenna Connect the pig tail cable from the antenna directly to the radio After you selected the site and the mast you are now ready to install the LAWNII PLUS system Plan your installation procedure carefully and completely before you start Successful installation is largely a matter of coordination and preparation When instal
32. The system number is set by the SYstem command The default of the SYSNUM is O Via LAWNIIs may route their messages through other LAWNIls that are used as the repeaters before reaching the final destination This is accomplished by naming the repeater path in the connect command as follows CONNECT JOHN VIA APRIL BOB CECIL DAVID The LAWNII supports up to seven vias Please be aware that each via adds more delay to the data path A LAWNII can connect to itself through vias This feature allows the user perform a loopback echo test easily For example CONNECT JOHN VIA JILL JACK JILL This command will connect JOHN to itself through two other LAWNIIs assuming the LAWNII initiating the connection is JOHN After the connection is established ever character the user send to JOHN will be echoed back through the radio chain immediately This feature is great for the diagnostic and debugging purpose It provides a round about way of sending data to yourself through the same mechanism that data is sent to others Omnispread Communications Inc 30 Baud rate The LAWNII supports baud rates from 300 to 38400 baud The baud rates are software select able The baud rate is set by the ABaud command The default is 9600 baud Radio channel The LAWNII has 3 channels of operation The three radio channels provide isolation for different systems and also provide a way to prevent inte
33. WNII at its last known configuration settings If this is the first time it is run then it will default to Comm 1 9600 n 8 1 If the program fails to communicate with the LAWNII it will prompt you to go to the Serial Port Settings tab to find the correct communications port and communications settings This is recommended because until this is done the LAWNII Configuration Program may not be able to communicate with the LAWNII After switching to the Serial Port Setting tab you should dlick on the Find Port button to find which communications port the LAWNII is connected to Follow the instructions as shown in the message box to find the port Be prepared to press the reset button or cycle the power supply to the LAWNII during the search After finding the communications port it is recommended that you then find the serial settings of the LAWNII To do so press Find Serial Port Settings button it is found below and to the right of the Find Port button By clicking the Find Serial Port Settings button the LAWNII Configura tion Program will begin to search the settings of the LAWNII This process may take up to two minutes but in most cases it will only take about one minute After finding the communications serial port and the serial settings you may now use the other features of the LAWNII Configuration Program Changing the LAWNII Serial Settings After finding the serial settings of the LAWNII you can change the LAWNII se
34. a height Although the radio wave will bend a little below the horizon it is recommended that you operate the radio only within the horizon for a real LOS condition Distance of horizon miles Height Required in feet 5 16 5 6 24 7 32 8 42 9 53 10 66 11 80 12 95 13 111 14 130 Chapter 17 Installation of the LAWNII Plus 55 As you can see the height requirement increase much faster than the distance The above table is just for the calculation of the distance of horizon In the real word there probably will have some obstructions like trees or houses on the way so that you need to add their height to the antenna height requirement Additionally the antenna needs to be mounted on a mast at least 10 tall so that there is some room against the multipath reflections from the ground As a result the antenna height require ment can be calculated as follows Total height of the antenna support Antenna height at the distance of horizon the height of the trees and other obstructions between the path For example if you are installing the radios at 10 miles apart the height requirement for a 10 miles horizon is 66 If one end is installed on the roof of a three story building and the roof is 40 tall and the other end is installed on a tower and you need to find out the height requirement for the tower You also notice that there are some trees about 30 tall between the two nodes You can find out the height re
35. accompanied by a message indicating that another LAWNII attempted to connect to your LAWNII NCACAC This may return three cmd or one cmd depending on the state of the LAWNII Datagram and beaconing To prevent unwanted characters in the receive data stream beaconing should be turned off for all Datagram LAWNII s in the system Datagram LAWNII s should not use UNPROTO CQ or use CQ in LCALLS if regular LAWNII s may be nearby Beaconing normally sends a space character in a Datagram packet Latency time Assuming that a LAWNII Plus is running at 9600 baud with the packet length of 256 bytes and the fastest packet time out PACTime A 1 the data will be sent in 8 msec to 20 msec after the last data enters the RS 232 port The LAWNII Plus will take up to 25 msec to process the raw data from the time that the radio receives the data to the time that the data shows up at the RS 232 port The total latency time of the system is under 50 msec which is from the time the data enters the RS 232 port of the transmitter to the time that the data appears on the RS 232 port of the re ceiver Omnispread Communications Inc 48 Chapter 12 LAWNII Error Counters The LAWNII maintains several counters with statistics of the LAWNII performance Each of the counters increments when a specific event occurs Several counters may be affected by one event The counters are reset to O by a RESTART The counts are observed with the DISPLAY command Each c
36. art of the radio wave will reach the destination At any rate an unobstructed path will improve the radio performance but it is not a necessity LAWNII employs an internal antenna inside the plastic housing Due to its physical limitation the internal antenna radiates most of its energy to the ceiling As a result LAWNII uses the ceiling or light fixtures above it as the main reflector to communicate with the other LAWNIIs To achieve the optimum network performance each LAWNII needs to have as much free space above it as possible The internal antenna is an excellent antenna for indoor applications The internal antenna is safe and will not break Each antenna is optimally tuned to match the input circuit and the antenna is not affected by the outside environment that might otherwise severely de tune the antenna in some applications As a result the radio s performance is very reliable and is always optimized The LAWNII is designed for indoor applications only If you need to send data outside a building you should use the LAWNII Plus product instead The LAWNII Plus is packaged in a NEMA 4X enclosure and has an option to use all kinds of antenna The Yagi antenna is normally used for point to point application it gives the user a great control over the signal path and also boost up both the transmitted and received signals The path control and signal gain from the antenna guarantees a great customer satisfaction for the years to c
37. board Connect test The connect test verifies the system settings of the LAWNII Plus The system settings include name channel and system number Please follow the example in Chapter 10 Examples to perform a connect test If you have done the Connect test on the bench you are still recom mended to do the test again to test the installation If the installation is successful the connection between the two radios should be established immediately as soon as the connection command is entered A slow or failed connection indicates installation problems Data test You may perform the Data test to verify the success of the installation of the LAWNII Plus system To perform the data test you will need to connect the two LAWNII Plus to two terminals and set the terminal s setting to match with the LAWNII Plus s setting You then follow the examples in Chapter 10 Examples to send characters from one terminal to the other and vice versa More on the antenna alignment If during the FCC test mode the receive LED remains solid for some time and then goes off quickly and then comes back on solid again This symptom is called fading which is normal espe cially for long range communications As long as the fade out period is brief say once every 10 seconds The path is still considered solid The LAWNII Plus should have no problem to catch up from the brief loss of path If you observe fading in a short range link under 2 miles y
38. contains the same information without the OCI logo and phone number Your label must have the same FCC ID number and warning message as the OCI s label However you may use a different model number and model name for the radio product if you wish to 2 Connector requirement The FCC requires that all unlicensed radios use a special connector for the antenna so that the end user can not change the antenna to a more powerful antenna off the shelf OCI satisfied this requirement by providing a short RF cable to convert the SMA connector on the board to a reverse N connector that is mounted on the outside case of the OEM final product As the OEM customer of the LAWNII Plus product you must make sure that the reverse N connector is the only connector that the end users have an access to by using some glue such as Locktite 404 to seal the SMA connector before shipping your product to the customer Chapter 1 Rules and Descriptions 19 Chapter 2 Programming the LAWN Using a Terminal or MS DOS Terminal Simulator 1 Set the terminal to 9600 n 8 1 Select the Wyse 50 or a similar terminal Set the terminal to HDX and choose NO flow control for handshaking If you do not have a terminal you may use a PC with a DOS based simulator program such as PROCOMM PCPLUS or Carbon Copy If you are using Windows please refer to the sections titled Using the Terminal Simulation Program from Windows 3 1 or Using the Terminal Simulation Program
39. ct a LAWNII Plusto a modem DCE emen 76 Connect a LAWNII Plusto a terminal eeseeeeeneeeeennnn nnns 77 Chapter 25 485 Option iii cad Anas aaO EUR CES 78 LAWNII Plus with 485 option coocccccocconcccnconononnconccnannnncncnorononnnnconronnnnonanon nc nr naar nn nnanos 78 485 Option forthe regular LAWNI eese nnne nennen nnn 78 LAWNII Plus OEM board with the 485 option eseeeeennnnnn 79 222 0DBOTI oun seb EU bte eno ee ctu erue a een uo ural ce Coma datas quud Debe e ea 80 T rtniniatioriarid Blas mois atada ara 80 Chapter 26 Using Repeaters for the Broadcast Mode 82 Seal repeater Seb ioter resisto S eoi clas tiara Mora a che eh Geek edna tae paisa 82 Parallel repeater SOE roo oceans a SNP SLE Casu ER rdc RE EN E 83 Performance Improvement by Parallel Repeating eeeeeeeeeeee 86 This equipment has been tested and found to comply with the limits for a Class B digital device pursuant to Part 15 of the FCC rules These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a residential installation This equipment generates uses and can radiate radio frequency energy and if not installed and used in accordance with the instruction manual may cause harmful inter ference to radio communications However there is no guarantee that harm
40. d has been issued not enough Not enough arguments were given for the command Omnispread Communications Inc AQ not while connected MYCALL can not be changed while the LAWNII is connected Other parameters such as the channel and system number are also not changeable while connected range An argument is too large too long The command line entered is too long too many Too many arguments were given on the command line VIA More than one name was issued for the connect command without a via valid baud rates are 38400 19200 9600 4800 2400 1200 600 300 This message appears if a valid baud rate is not used valid channel numbers are 1 2 3 4 This message is used if a invalid channel is specified cannot change Many parameters in the LAWNII are locked in the firmware and cannot be adjusted by the user This message appears if one of those commands is issued with a value Link status messages Link status messages are returned by the connect command with no arguments Link state is CONNECTED to NAME This will occur if the LAWNII is connected to NAME Chapter 9 Messages from the LAWNII 41 Link state is DISCONNECTED This will occur if the LAWNII is not connected Link state is CONNECT in progress This will occur if the LAWNII is attempting to connect to another LAWNII Link state is DISCONNECT in progress This will occur if the LAWNII is attempting to disconnect from another LAWNII Link
41. d have been locked to the user These commands will be listed with the DISPLAY command but are not available to the user The LAWNII command processor requires only partial commands to distinguish among its command set The required letters are underlined in the command description ABAUD n Default 9600 Sets the serial port baud rate Valid baud rates are 38400 19200 9600 4800 2400 1200 600 300 This command is an immediate command Upon the receipt of this command the LAWNII will switch to the new baud rate immediately The user will have to change the computer s or terminal s baud rate immediately after issuing the new baud rate command if the user wants to send more commands to the LAWNII Example AB 38400 will set the LAWNII s baud rate to 38400 immediately AUTOLF ON OFF Default Off If ON a line feed is added after each carriage return is entered in the command mode If OFF all characters are passed as received This command is very useful when the user is communicating with the LAWNII through a terminal Without the auto line feed all the conversations between the LAWNII and user are displayed on one line Example AU ON will turn on the auto line feed AWLEN 7 8 Default 8 Defines the word length used by the serial port The value can be either 7 or 8 The LAWNII will not change to the new word length immediately The new word length will be in effect after the reset either software or hardware or power on of
42. d mode disconnect from STEVE Comment put the LAWNII in transparent mode and wait for the connection to be established by the other LAWNII read the other LAWNII s sent data here send CTRL C to get back to command mode return to command mode after disconnect Comment name the LAWNII establish a loopback connection the connect light of STEVE should be off the connect light of TEST should be on type any key here and it should be echoed right back through STEVE Chapter 10 Examples 43 Master slave network An example of how to setup a master slave network to replace RS 485 or similar networks follows All of the data from the master will be sent to all slaves The data from all slaves will be heard only by the master There is no limit for the number of slaves in a system The master slave broadcast network can move data faster because the data is broadcasted and no acknowledgment from the receiving unit is required As a result the latency time of a broadcast network is only half of the latency time of a connection oriented network The broadcast network however does not guarantee the delivery of data If the data got lost it is lost The LAWNII will not resend the bad packet The user has to deal with the possibility of losing data in the user s proto col The master slave network is also called a multidrop network This LAWNII master slave network can replace a typical RS 485 wired multidrop network
43. data and a power jack The power jack and the DB9 are right next to each other Normally the DB9 male plug can be longer than 1 so you should allow room with 2 of clearance for the side with the DB9 connector You also need to allow 1 of clearance for the side with the SMA connector Since the status LEDs are on the same side as the SMA connector you should always make this side easily visible Left Radio on top Right Processor on top Omnispread Communications Inc 18 FCC Rules for Customers Using LAWN II Plus OEM Board Since the LAWNII Plus OEM board is unlicensed you as the OEM user are responsible for complying with the FCC s labeling and connector requirements 1 Labeling requirement It is required by FCC that every part 15 radio product must have a warning label about interfer ences on the outside surface of the product The warning label should also include the FCC ID of the radio To comply with this rule OCI supplies a warning label with every LAWNII Plus OEM board You as the OEM customer must apply this label to the outside surface of your product so that the end user can read the warning messages and the FCC officers can identify the radio without opening the enclosure when they are investigating an interference problem The label provided by OCI contains the OCI logo and an 800 technical support phone number If you do not want your end user know about this information you may print your own label that
44. e RS 232 cable by using the DFC mode In this mode the virtual connection between the LAWNIIs will be established automatically as soon as the data enters the serial port of either LAWNII The connection may be kept on until power up reset occurs or after the disconnect time out expired Program the two LAWNIIs as follows Commands for Host Commands for Remote AUTO ON AUTO ON MYC HOST MYC REMOTE DFCN REMOTE DFCN HOST DFC ON DFC ON Ger SCA CAG SAVE SAVE The RS 232 port and packet specifications of the two ends need not be the same For example if you are connecting a terminal to a computer by using LAWNII s the packet size of the LAWNII that is connected to the terminal should be set to 1 and the packet size should be 256 for the LAWNII that is connected to the computer This is because that the input from terminal is key stroke and the computer should respond to it right away by quickly updating the terminal screen whenever the user hits the keyboard of the terminal By using packet size of 1 the keystroke will be sent immediately whenever it occurs This will minimize the latency time for the user And the computer will quickly send a lot of information back to the terminal by using a large packet size for maximum data throughput The baud rate of the LAWNII attached to the terminal can be 300 baud while it can be 38400 baud for the LAWNII connected to the computer All LAWNIIs use the same 76 8Kb data rate over the air so that the
45. e best location for the antenna The reflections from the water tank is usually determined by the shape of the water tank Assum ing that the remote end of the system is at a lower altitude than the water tank for example as shown in the figures below on the left the antenna on the top of the tank will pickup more reflec tion than the antenna at the bottom of the tank due to the descending slope of the tank and the condition is reversed if the slope is ascending as shown in the figure on the right More reflection Less reflection from the tank from the tank main main signal 1 o signal MM P NC reflected signal a signal Mumain alma main Less reflection main signal More reflec hon sional from the tank Es from the tank j 10 Ez reflected signal Chapter 18 Support Selection 61 The user can mount the antenna directly on the guard rail however an U bracket about one foot wide is recommended The U bracket will keep the most part of the antenna away from the structure of the guard rail and reduce the effect of guard rail to the minimum Guard rail 1 wide U bracket Tues It is not a good practice to install the antenna under the shade of the water tank If it is the only place available you will need a large U bracket to keep the antenna out of the shade of the water tank as shown in the figure at left The side of the water tank is the best place to mount the antenna si
46. easily The LAWNII works transparently to the users protocol The only modification that might be required to the users polling software is that the host computer must allow for a longer response time from the remote drops since the LAWNII needs time to process the data packet The latency time of the LAWNII can be from 25msec to 50msec one way depending upon how the data packet is built Program the master as follows Command Comment AUTO ON so you can see the conversation easily MYC MASTER name the master DFCN MASTER put into peripheral mode SYS 0 use default system number CHA 2 pick a channel PACTIME A 1 send after 3 ms of no characters BE E 0 turn off beacons UNPROTO SLAVE send data to LAWNIIs with LCALLS SLAVE LAWNGRAM ON prevent addresses TRANSGRA ON allow monitoring in transparent mode LCALLS MASTER listen only for packets to master SAVE save settings to LAWN TRANS go to transparent mode Omnispread Communications Inc 44 Program all the slaves as follows Command Comment AUTO ON so you can see the conversation easily MYC SLAVE name the SLAVE DFCN SLAVE put into peripheral mode SYS 0 use default system number CHA 2 use same channel as MASTER PACTIME A 1 send after 3 ms of no characters BE E 0 turn off beacons UNPROTO MASTER send data to LAWNIIs with LCALLS MASTER LAWNGRAM ON prevent addresses TRANSGRAM ON allow monitoring in transparen
47. er tests To check the antenna alignment you will need to send the FCC command to one of the radio to turn on the transmitter and go to the remote end and observe the Received status LED If the antenna is aligned properly the Received LED should stay solidly on If the LED is flickering it indicates that the alignment could have problems or the installation site is not good the path between the antenna is obstructed or problems with the radios Omnispread Communications Inc 272 Then check the receiver s antenna alignment you will need to rotate the receiver s antenna from 90 degree to 90degree from the direction to the transmitter If the antenna path is good you should see the Received LED comes solidly on for a continuous span around the direction to the transmitter You then fix the antenna to the middle of the continuous span The angle of the continuous span can vary from 10 degrees to 60 degrees If the angle is less than 10 degrees the signal strength might be too weak If the LED only comes on sporadically then the multipath will severely deteriorate the radio s performance You should either raise the height of the mast or relocate the antenna to a better location After adjusting the receiver s antenna you will need to repeat the same test by sending the FCC command to the receiver and checking the Received LED on the transmitter You can exit the FCC mode by simply typing any character on the key
48. f cycle occurs Example AW 7 will set the word length to 7 bits at the next restart if the SAVE command is issued after it BEACON EVERY N BEACON AFTER N Default E 12 The purpose of beaconing is to let other LAWNII users know the presence of your LAWNII so that Omnispread Communications Inc 32 your LAWNII s name will show up in the other LAWNII s user list The BEACON command sets the time interval to send a beacon in 3 3 sec increments O turns off beaconing completely The EVERY parameter sets the beacon to occur at every Nx3 3 seconds The AFTER parameter sets the beacon to occur after INx3 3 seconds of no packet activity However only one beacon is sent Example BE E 99 will send out a beacon every 5 minutes and 26 seconds BREAK Causes a break to be sent to the RS 232 port of the remotely connected LAWNII This is intended to support a remote modem where breaks may be required at the remote computer BREAKLN n Default 2 Length of break to be sent to async port of the remote connected LAWNII in 33 3 msec incre ments CHAN 1 2 3 4 Default 2 Sets the LAWNIIs channel of operation The frequencies for the channels are CHA 1 90745 MHz CHA2 914 81 MHz CHA3 92110 MHz CHA4 914 814 MHz CMDTIME n Default 1 Sets the delay required before the C C C sequence to get back to the command mode Measured in 1 second increments CONNECT name If no name is specified then this command returns the
49. ful interference will not occur in a particular installation If this equipment does cause harmful interference to radio or television reception which can be determined by turning the equipment on off and on the user is encouraged to try to correct the interference by one or more of the following measures Reorient or relocate the receiving antenna Increase the separation between the equipment and the receiver Connect the equipment into an outlet on a circuit different from that to which the receiver is connected Consult the dealer or an experienced radio TV technician for help Omnispread Communications Inc LAWNII Plus Tested To Comply with FCC Standards FOR HOME OR OFFICE USE Declaration Of Conformity In accordance with FCC Rules and Regulations Code of Federal Regulations 47 part 15 Tested To Comply With FCC Standards FCC Rule Part 15 for Digital Devices Manufacturer s Name Omnispread Communications Inc 809 N Bethlehem Pike C6 P O Box 248 Spring House PA 19477 Type of Equipment Wireless RS 232 Radio Modem Model Number LAWNII Plus model 210 Year of Manufacture 1997 October 30 1997 the undersigned hereby declare that the equipment specified above conforms to the above standard Wen T Lin President Omnispread Communications Inc Test Facility Washington Laboratories Ltd 7560 Lindbergh Dr Gaithersburg MD 20879 NVLAP 200066 0 This equipment has been tested and fou
50. gram and Deacon 2 1 itt ii 48 E A dudes b poesi act ada tE adaa a iaiia 48 Chapter 12 LAWNII Error Counters cmcccccococonnnnnccccononannnnnn narran 49 Chapter 13 Tips to Using the LAWNII for Indoor Applications 50 Chapter ME DUO is iiic csviadsasisedececasvaadedasswadavevasnduascncnadocduusavanatuuecaueussveasusanecasoumasdcnds 51 Internal Battery Option for LAWNII BAT cc cccsccssseeeessssteeeessseereeesessneeeeeesenaneeeees 51 Atenas AS 51 Chapter 15 Description of the Circular Connector on the LAWNII Plus 52 Wiring Diagram of the Circular to RS 232 Cable seen 53 Chapter 16 LAWNII Plus Spec ific ations eeeeeee eere eee eee ne nnns 54 Chapter 17 Installation of the LAWNII Plus 1e enne eer 55 Introduction to LAWN II Plus installation 55 Antenna Height Requirement for long range applications more than 5 miles 55 lasta latio N oorr Gee e Oen tab A da Fas he ed rre De eden T Ra pu De Dapur s 57 Site Selecto Mr a aa 57 Chapter 18 Support selection sscasmimaniononcani nnne conan an aa nsi o ERRREN Kan UR i cR C EEERRRR VAN RR oC CER RN n 60 ROOM gio PR ec 60 Telescoping Md Sb ies a c pula 60 Side OT House MOULE sa aid 61 Watertank guard rail PrYo bib ios eoi ener papa avi due ee uta rea neve Ue ecran 61 Ower rersigudese mL 63 Chimney MOLDE sod riot id bes 63 Chapter 19 Polarization
51. he ground rod via a twisted pair of 10 copper wires so that it becomes the lightning rod for your system A proper grounding will protect the system from lightning strikes The ground rod itself must be buried into the earth for at least ten feet Please only use noncorrosive hardware for the grounding system If you have difficulties to install the ground rod you may connect the ground wire to the sewer or water line instead A ten feet ground rod is usually sufficient for most area in this country to reach a stable ground water level which provides the conductive ground for the electric system The effectiveness of the ground rod totally depends upon the moisture contents in the soil A dry earth will greatly degrade the perfor mance of the lightning rod If this is the case you will need to bury the ground rod deeper until it reaches the ground water level or connect the ground system to the sewer or water line Chapter 21 The Mast Selection 67 Chapter 22 Installing the LAWNII Plus system Bench functional check Before you install the LAWNII Plus system you need to first set them up and test them on the bench You do not need to connect the LAWN II Plus to the antenna for the bench functional test although it will always work better with the antenna connected Simply connect the serial cable from your PC or laptop to the LAWNII Plus and plug the power cube to the outlet Only the Power LED will remain solid ON at this moment You then
52. he user can connect the LAWNII Plus to a terminal or PC directly The pin arrangement of the circular connector is almost the same as a normal DB9 connector except that the pin 9 is used as the power supply input for the radio The pin assignments and functions of the circular connector are as follows Pin Name Dir Description 1 DCD Out Indicates the LAWNII Plus is connected 2 TXD Out Transmit data from LAWNII Plus 3 RXD In Receive data to LAWNII Plus 4 DIR In Hardware handshake to hold data from LAWNII Plus 5 GND 6 DSR Out Indicated that LAWNII Plus is powered 7 RTS In Hardware handshake to hold data from LAWNII Plus 8 CTS Out Hardware handshake to hold data from computer 9 PWR In Power supply to the LAWNII Plus Pin 4 or 7 may be used for flow control of data from LAWN lI Plus The LAWN IlI Plus includes pull up resistors on its flow control input lines lt can operate with only 3 wires RXD TXD and GND if flow control is not required or if software flow control XON XOFP is used DCD indicates that LAWN II Plus has a virtual connection between itself and another Omnispread Communications Inc 352 Wiring Diagram of the Circular to RS 232 Cable 00000 0 O Above The circular connector Top Right The RS 232 Connector Bottom Right The power connector Circular Connector RS 232 Connector 209 6 0 1 DCD 1 Zo TXD e 2 3 RXD 3 4 DTR 4
53. her is one year The following is the procedure to install the aluminum raincoat 1 Connect the low loss RF cable to the LAWNII 2 Slightly push the top lid open so that the cable can be run through the gap between the top lid and the side lid The cable can be run through either the right gap or left gap Please be careful when running the cable through the gap The black PVC cover of the cable prevents the mois ture from coming inside the cable and causing corrosion problem You have to make a final visual inspection of the cable at the end of LL gt installation to make sure that there is no cut or Z Y puncture hole on the black PVC cover If there is 7 lame Lid a cut or puncture hole then you have to seal it with a cold shrink tape right away Right Lid 3 Position the LAWNII so that the LAWNII can be installed to the aluminum raincoat through the four mounting screws If you decide to install the radio indoors and use a low loss RF cable to connect the radio to the antenna on the roof top you must use the cold shrink tape as provided by OCI to seal the con nectors of the antenna and cable to protect them from the weather Installing the Cold Shrink Tape OCI now supplies a three foot long cold shrink tape with each low loss RF cable You must use this cold shrink tape to seal the metallic part of the connectors on the cable and antenna to protect the connectors from the weather after they are connected together
54. ill be broadcasted and the sending LAWNII will be heard by all other LAWNIIs However no LAWNII will be able to extract the data The Traffic LED will indicate that data was received While in the transparent mode the data received by a LAWNII is sent to that LAWNII s serial port There is no protocol between the LAWNII and the device that it is connected to The data is sent unsolicited from the LAWNII to your devices except when your device s buffer is full and enables the brake by asserting the flow control signal to the LAWNII Data may be received by a LAWNII that is in the command mode from another LAWNII that is in the transparent mode However that data will be stored in the LAWNII until the LAWNII enters the transparent mode If the receiving LAWNII fills its buffer then the transmitting LAWNII will hold off the sending computer through the handshake until the receiver has space for more data Return to command mode from transparent mode The LAWNII will return to the command mode from the transparent mode if it receives a BREAK on its async input The LAWNII will also return to the command mode if it receives the following wake up sequence on the async port one second of no activitylL CIL CI Cllone second of no activity If the LAWNII is in the peripheral mode as described below then the asynchronous break does not return the LAWNII to the command mode The power up or down cycle of many peripherals looks like an async BREAK
55. ined in this manual and associated software shall not be reproduced in whole or in part without prior written approval of OCI OCI reserves the right to make changes in specifications and other information contained in this manual without prior notice The reader shall in all cases consult OCI to determine whether any such changes have been made LAWNII User s Manual rev D 08 2003 Copyright O 2003 Omnispread Communications Inc Omnispread Communications Inc 809 N Bethlehem Pike C6 P O Box 248 Spring House PA 19477 All rights reserved Trademark Information LAWN is a registered trademark of Omnispread Communications Inc The LAWN logo OCI and the OCI logo are trademarks of Omnispread Communications Inc Other Information The LAWNII Plus system hardware is proprietary to Omnispread Communications Inc Patented in the United States of America and other countries LAWNII Plus User Software Copyright O 1997 Omnispread Communications Inc All rights reserved Omnispread Communications Inc X LIMITED WARRANTY Omnispread Communications Inc COCI warrants to the original purchaser that the LAWNII will operate substantially in accordance with the description provided in the accompanying docu mentation the Documentation OCI also warrants the hardware will be free from defects in materials and workmanship under normal use This warranty does not cover the Datagram LAWNII with Ni Cd battery
56. is sending signals to the air Omnispread Communications Inc 12 Description of the Top Panel of the LAWNII Plus Above The LAWNII Plus antenna connector Chapter 1 Rules and Descriptions 13 Description of the Interface Connectors of the LAWNII Plus OEM Board Left The LAWNII Plus OEM board interfaces front 1 Left to Right Power Traffic Connect Transmit 2 DB9 female connector 3 Power Jack 2 1 mm center positive Left The LAWNII Plus OEM board interfaces back 1 SMA Connector Omnispread Communications Inc 14 Installation of LAWNII Plus OEM 3 177 Right Location of the mounting holes on the LAWNII Plus OEM board The holes are 1 in diam TUE 3 090 eter 2 675 1 000 Left Antenna connector 7 1 0 1 000 s mounting hole locations Below Antenna connector L cable 110 Dia ETE g 375 Dia 8 00 SMA Plug Reverse N Female Chapter 1 Rules and Descriptions 15 Description of the Front Panel of the LAWNII Above The front panel of the LAWNII Power A red LED that indicates the LAWNII is powered up Traffic A green LED that indicates the presence of radio carriers Connected A green LED that indicates the LAWNII is virtually connected to its destination and it is not available to other LAWNIIs Transmit A green LED that indicates the LAWNII is sending signals to the air Omnispread Communications Inc 16
57. le it is charging It will only take a little bit longer to fully charge the battery if you operate and charge it at the same time Never charge LAWNII BAT with other chargers They might cause permanent damage to the charging circuit and battery inside The battery of LAWNII BAT should last for 300 charging discharging cycles if the battery is oper ated according to the above guidelines with a normal charger Antenna The LAWNII Plus can be used with high gain up to 13dbd Yagi or omnidirectional antennas to increase the coverage range The Yagi antenna is normally used for fixed line of sight applications while the omnidirectional antenna is mainly used for mobile applications or the host computer of the wireless network The mast of the antenna needs to be grounded properly to prevent the damage caused by light ning The proper way of grounding is to connect the mast to the ground rod by using a twisted pair of 10 copper The ground rod should be buried deep enough to reach a stable ground water level Please refer to the LAWNII Plus installation guide for the antenna installation Chapter 14 Options 51 Chapter 15 Description of the Circular Connector on the LAWNII Plus A weatherproofed circular connector instead of a standard DB9 connector is used for the LAWNII Plus product so that it can be operated outdoors OCI also supplies an interface cable that convert the circular connector to a standard DB9 connector so that t
58. ling the system remember do not use a metal ladder Do not work on a wet or windy day Do dress properly shoes with rubber soles and heels rubber gloves long sleeve shirt or jacket If the antenna or other parts start to drop get away from it and let it fall Remember the antenna mast guy wires and cable are all conductors for electricity current Even a slightest touch on any of these parts to a power line can kill you If any part of the system should come in contact with a power line DO NOT TOUCH IT OR TRY TO REMOVE IT YOURSELF Call your local power company They know how to do that safely Omnispread Communications Inc 70 Adjust the location of the radio so that the pig tail antenna cable will follow the backbone of the antenna and then along the mast to the radio Rotate the mounting bracket of the radio so that the mounting plate is in parallel to the antenna as shown in the figure below Please use some electrical insulation tape to hold the antenna pig tail cable to the mast and the backbone of the antenna so that it will not hang loose Connect the serial cable to the radio If the cable will enter the building through a hole make sure that the hole is larger than the circular connector Since the circular connector is the smaller end of the cable you must first pass the end of cable with the circular connector from inside of the building out to the antenna Please use electrical tape cable ties or clamps
59. llic objects at the back of antenna will not affect the antenna as much 2 be located as high as possible You must always choose your antenna site following the above rules For example in the next figure the antenna location marked as best without doubt is the one on the top of the building with a tall mast If a tall mast is not available the better location will be the one on the front of the building because there is no metallic reflector in the front The location on the roof top with a short mast although it is higher is not the better location because there are more reflectors from the roof and siding The antenna location at the rear end of the house will have a range problem because the siding reflects most of the signal away Best Omnispread Communications Inc 58 In the above figure since all antennas are pointing away from the house and roof all these locations are acceptable and the one with a tall mast is the most desirable location Good B a d The omnidirectional antenna should always be mounted at the tallest point of the building Chapter 17 Installation of the LAWNII Plus 59 Chapter 18 Support selection After you have determined where to install the mast now is the time to determine how to support the mast and antenna The following are a few common installation methods for your reference Roof mounting Using a tripod mounting bracket or a swivel universal roof mounti
60. me longer than the user defined time out When new data arrives the whole process will repeat The DFC Mode is most useful for one to one communication that requires 100 data integrity The data will be re sent automatically if the receiving unit does not send back a positive acknowl edge to the sending unit The data is guaranteed to be delivered with 10096 accuracy The user can simply treat the LAWNII as a smart cable that guarantees the data delivery The LAWNII exerts flow control to handle any delay in establishing the connection The LAWNII remains in the transparent mode If there is no activity on the RS 232 port for a user defined time out period default 45 seconds then the LAWNII initiates a disconnection from the destination LAWNII The LAWN remains in the transparent mode afterward without sending any message to the device it is connected to The LAWNII will enter the DFC mode when it receives the DFC ON command This will cause the LAWNII to go into the transparent mode immediately Power up or reset also cause the LAWNII to enter the transparent mode if the DFC is on Datagram mode The Datagram mode provides unconnected data communications between two or more LAWNII s The data is sent as unconnected packets without protocol The data between LAWNII s is checked for errors and only correct packets are sent to the RS 232 port The Datagram mode provides a method for a user to send a message to a specific user or to all users
61. n on the RS 232 port for the length of the time out the connection is disconnected The unit of Time out is 3 3 seconds A setting of O prevents time out disconnect only a hardware reset power on off cycle or the DIS CONNECT command can disconnect the link TRANSPARENT Causes the LAWNII to switch from the command mode to the transparent mode In the transpar ent mode all data entering the LAWNII is sent over the air through the packetizing mechanism If no connection exists then the data is sent to CQ a universal address However no LAWNIIs can receive this data and send it out to the serial port After switching to transparent mode the user should wait for at least 50 msec before sending characters to the LAWNII TRFLOW ON OFF Default OFF Enables software flow control XON XOFF handshake on RX line TRIES Returns the number of retries of the current packet if not yet acknowledged or the number of retires required for the last packet if it has been acknowledged TXFLOW ON OFF Default OFF Enables software flow control XON XOFF handshake on TX line XFLOW ON OFF Default OFF Omnispread Communications Inc 38 Master switch for XON XOFF handshake Overrides TRFLOW and TXFLOW commands Chapter 7 Datagram Commands LAWNGRAM ON OFF Default OFF If ON the LAWNIIsuppresses the source and destination name and formatting of the monitored packets If OFF the source and destination are displayed along with o
62. nce the antenna can see the Use a large U bracket tO most free space at this location If you have to keep the antenna away mount the antenna on the top of the water tank from the shade of the water tank you should use a tall mast so that the height of the mast is taller than the distance between the antenna and the edge of the water tank Water tower is also a very popular place to mount the antenna for the cellular and pager system Since these systems are allowed to transmit a lot more power than the LAWN II system you should mount the LAWN II s antenna away from the other antenna as far as possible and also install a notch filter with the LAWN II s antenna to keep the pager and cellular s signal from affecting the LAWN II system Please call OCI to order the notch filter Omnispread Communications Inc 62 You should also keep the LAWN II s antenna away from the parabolic dish antenna since it is a perfect reflector with gain The LAWN II s antenna should always be installed behind the parabolic dish not before above or below If you have to mount the LAWN II s antenna with a parabolic antenna on the same mast you will need to space the two antenna so that the reflections from the dish will not reach the LAWN II s antenna as shown below good good no good No good Tower Mount To survive the wind loading a tower must be build upon a solid foundation of concrete or a tower mounting plate The tower also m
63. nce this is a loop back test the data throughput will be twice faster if you send the data only one way Using the LAWN Wizard The LAWN wizard is designed to ease the installation of the most common network designs for the LAWNII system the master slave networks and one to one networks To start the LAWN Wizard click View LAWN Wizard in the menu of the LAWNII Configuration Program Then you can follow the onscreen directions and the wizard will quickly finish the installation process for you Chapter 2 Programming the LAWNII 25 Chapter 3 Overview The LAWNII provides a method for two devices with RS 232 interfaces to communicate with each other by using a connection oriented service The LAWNII can also support an unconnected broadcast network to replace the wired RS 485 multidrop network In the connection oriented service the LAWNII operates by establishing a virtual connection between one computer and another computer or printer etc The connection must be estab lished before the data transfer begins The connection can be established manually by sending a command to the LAWNII or automatically by send any data to a LAWN II that is operated in the DFC mode After all the data has been sent to the destination LAWNII the connection can be terminated manually by sending another command to the LAWNII or automatically after the connection time out expired in the DFC mode Each LAWNII may have only one active connec
64. nd to comply with the limits for a Class B digital device pursuant to Part 15 of the FCC rules These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a residential installation This equipment generates uses and can radiate radio frequency energy and if not installed and used in accordance with the instruction manual may cause harmful inter ference to radio communications However there is no guarantee that harmful interference will not occur in a particular installation If this equipment does cause harmful interference to radio or television reception which can be determined by turning the equipment on off and on the user is encouraged to try to correct the interference by one or more of the following measures Reorient or relocate the receiving antenna Increase the separation between the equipment and the receiver Connect the equipment into an outlet on a circuit different from that to which the receiver is connected Consult the dealer or an experienced radio TV technician for help Omnispread Communications Inc LAWNII Plus OEM Tested To Comply with FCC Standards FOR HOME OR OFFICE USE Declaration Of Conformity In accordance with FCC Rules and Regulations Code of Federal Regulations 47 part 15 Tested To Comply With FCC Standards FCC Rule Part 15 for Digital Devices Manufacturer s Name Omnispread Communications Inc 809 N Bethlehem
65. new cmd prompt to the user for the next command The LAWNII has separate queues for the input and output Therefore it is not necessary to wait for the response from one command before issuing another command Flow control on the serial port will prevent overrunning the input buffer Normally the LAWNII will be set to the transparent mode as a peripheral device so that it can send or receive the data for you transparently That s why you bought it Once the LAWNII is set as a peripheral device in the transparent mode it will always be powered up in the transparent mode If you set the LAWNII to the command mode to change the settings and did not return to the Chapter 4 Operation Modes 27 transparent mode before turning the power off the LAWNII will be in the command mode when it s powered up again unless it is programed as either a peripheral device mode or the DFC mode as described below In this case you will need to send the Transparent command to the LAWNII before it can send or receive data for you Transparent mode The transparent mode is the normal mode for the communication between two LAWNII s In the transparent mode all the serial port input or output are treated as data Transparent mode is entered via the Trans command In the transparent mode all data passed to the LAWNII is transmitted to another LAWNII If no virtual connection is currently in effect and the LAWNII is not in the broadcast mode the data w
66. ng bracket to support the mast on the roof Guy wires are needed for the swivel universal mounting bracket Place three or four guy wires equally spaced around the mast and anchored to the roof Apply roofing compound around the base of bracket to seal the roof To Ground Rod Signal Data I O Telescoping Mast Guy wires should be equally spaced in at least three directions around the mast Use at least three guy wires for each ten feet section of mast For example if the mast is 35 three sets of guy wires each set includes three guy wires that hold the mast at 10 20 30 above the ground will be needed So a total of 9 guy wires are needed Omnispread Communications Inc 60 Side of House Mount The side of house is a very convenient place to mount the mast Position two brackets over studs that are at least two or three feet apart To Ground Rod Water tank guard rail mount Signal Data I O The water tank is the best place to install the antenna since it is usually high above the surround ings and provides a great line of sight condition for the antenna The guard rail around the water tank is usually a good place to mount the antenna Since the antenna on the water tank is so high above the ground it does not pick up much reflec tions from the earth Nevertheless the water tank itself can produce some undesired reflections to the antenna The user should follow the guidelines below to carefully select th
67. ng of the LAWNII by removing the hassle of manually changing the communications port settings when using a program such as Hyperterminal or other terminal emulators The Find Comm Port function is also retained as well as an improved version of Find Comm Port Settings There are four tabs in the main LAWN 3 0 program menu They are 1 Serial Port Settings 2 LAWN Settings 3 Terminal and 4 Loop back test The Serial Port Settings tab is used to find or change the serial settings of the LAWNII The LAWN Settings tab is used to find or change some of the basic LAWNII s settings The Terminal tab is a terminal emulator that is designed specifically for the LAWNII The Loop back test tab is used to test the basic performance of the RF link Omnispread Communications Inc 222 Installing the LAWNII 3 0 Configuration Program 1 Insert the CD ROM titled LAWNII Configuration Program and Users Manual into your CD ROM drive 2 If the setup program does not start automatically click on Start gt Run and type D Setup setup exe where the D corresponds to the letter of your CD ROM drive 3 Click OK 4 Follow the onscreen directions of the setup program Getting Started with the LAWNII Configuration Program 3 0 Launch the program by selecting the icon under the Omnispread Communications folder from the Start menu When the LAWNII Configuration Program 3 0 loads up it will attempt to com municate with the LA
68. o be a timed interval of every Nx3 3 milliseconds AFTER sets the pack ets to be sent after Nx3 3 milliseconds of no activity on the async port Packets are sent when PACLEN data bytes have been received on the async port or the PACTIME has expired For example the following two commands PACT A 1 P0 will send the packet with packet size of 256 bytes after a continuous 256 bytes are received from the serial port If the 256 bytes coming from the serial port has a pause of 4 msec between the 1st byte and 2nd byte then the 256 bytes will be sent as two packets one containing only one byte and the other containing 255 bytes PARITY n Default O Sets the parity on the async port Data is always sent on the RF link in 8 bit mode If the data length is set to 7 bits then the parity bit or stop bit is sent to the destination LAWNII Omnispread Communications Inc 36 O no parity 1 odd parity 2 no parity 3 even parity RESENDS n Returns the number of retransmissions of packets Reset to O by using parameter O This com mand is useful to evaluate the robustness of the radio path A robust link should not need to resend any packet For example before you send the data enter the RESEND 0 command to dear the resend counter After you finish the data transfer enter the RESEND commend and the radio will return the number of resend packets to you RESET Resets LAWNII to the factory default values The LAWNII will have
69. o the ground and theoretically save your equipment If you install LAWN II Plus on the mast with the antenna then there is no such problem of speed difference because the cable that comes down to your equipment is an un shielded 9 conductor RS 232 cable Your best bet to survive a lightning strike is to prevent it in the first place You can do it by providing a good ground for the mast It is hard to survive the lightning strike after you get hit even if you install the best lightning protector All the energy from the lightning strike must go somewhere Even if you install the best lightning protector in the world you still have to make sure that you have an effective ground system that will bypass the lightning to the earth If you do not have a good ground system the energy from the lightning will still hurt you A good ground is the only thing that you can count on to prevent a lightning strike Omnispread Communications Inc 66 Chapter 21 The Mast Selection Since the LAWNII Plus system is very light a mast with 1 to 2 O D will be sufficient to hold the antenna and the radio The height of the mast depends upon the location that it is mounted to Do not mount other antenna or anything that is metallic on the same mast with the LAWNII Plus If you have to mount the other antenna on the same mast you must space them out and use different polarity for the antenna to reduce cross coupling The mast itself must be connected to t
70. ome The do s and don ts of using LAWNII indoors are shown here Please follow these guidelines for the best results Don t ZZ f Omnispread Communications Inc 50 Chapter 14 Options Internal Battery Option for LAWNII BAT The charging time of the battery is about 2 hours with a fast charger or 12 hours with the normal charger The operating time of a fully charge battery is about 7 hours The life of the battery is primarily determined by the cycles of charging and discharging The degree of charging and discharging also plays an important role Please do not let the battery drained out completely Plug the LAWNII BAT to its charger immediately when the low voltage warning buzzer sounds The buzzer sounds at least 5 minutes before the battery is running too low so that you have plenty of time to prepare for the shutdown The running time you have after the buzzer sounds the first beep may vary from 5 to 30 minutes depending upon the charging conditions of the battery Since the battery monitor will consume current regardless of the operat ing condition of the LAWNII BAT please keep the LAWNII BAT plugged to its charger and with the power switch in the OFF position when it is not in use This will prevent the battery from discharging But if you do not plan to use the LAWN BAT for a while please disconnect it from the charger to prevent maintenance charging and extend the battery life You may operate the LAWNII BAT whi
71. ote that the DISPLAY command is not available to a LAWNII that is in the peripheral mode Omnispread Communications Inc 34 ECHO ON OFF Default ON Sets LAWNII to echo data from the async port if in the command mode FCC Sets the LAWNII to the FCC test mode This command locks the LAWNII s transmitter on and transmits all ones A lt CR gt turns the FCC test mode off No communication on the selected chan nel is possible by other LAWNII if any LAWNII is in FCC mode This FCC mode is useful for setting up and aiming the antennas of LAWNII Plus in outdoor communications The user can lock on the transmitting LAWNII Plus and observe the traffic light of the receiving LAWNII Plus while aligning the receiver s antenna A solid traffic light indicates a solid radio link HF ON OFF Default OFF The command to turn on off the hardware flow control MHEARD Displays the name of users of this system The LAWNII will store up to 18 names LAWNIIs that are heard through a via path have a appended to their name Changing the channel or the system number does not affect the mheard list immediately There fore the mheard list may have invalid data after either of these parameters is changed To prevent this problem the MHEARD list should be cleared with a MHCLEAR command after changing the channel and system number User may extend the length of the MHEARD list by polling the LAWNII every few seconds and building a list in the
72. ou will probably have to raise the antenna height or find a better location for the antenna The fading is most likely caused by the reflections from the earth When you use a taller mast for the antenna you can increase the path difference between the direct wave and reflected wave from the earth and thus decrease the depth of fading It you have raised the antenna to the maximum height you possibly can get and the multipath or fading problems are still there you may try a different polarity for the antenna Normally vertical polarization is preferred in order to minimize the effect of ice and snow during the winter How ever if the multipath is giving you a problem you then have no other choice but to use the hori Chapter 23 System Check and Functional Test 73 zontal polarization for the antenna The horizontal polarization usually has less multipath signals due to its narrower beamwidth If you run out of choices the last thing you can do is to tilt the antenna upward to the sky by 10 to 30 degrees instead of aiming at the same level as shown in the following figure The reason that tilting the antenna can solve the multipath problem is due to the fact that the multipath signals are most likely generated from the earth or metallic objects on the ground By tilting the antenna the antenna can effectively reduce the pickups of ground reflections As a result the multipath problem is solved However the more tilt you use the le
73. ount is listed with the event that causes it to increment ASYRXOVR overruns from async port DIGISENT frames digipeated HOVERR receiver overruns in HDLC link HUNDERR transmitter underruns in HDLC link RCVDFRMR frame reject frames received RCVDIFRA frames received RCVDREJ REJECT frames RCVDRNR receive RNR packet RCVDSABM SABM frames received RXABORT received abort in data RXCCOUNT frames received with good CRC RXERRORS bad frames received RXLENERR packets received that are too short RXRESYNC receiver resync after error SENTFRMR frame rejects sent SENTIFRA frames sent SENTREJ REJECT frames sent SENTRNR transmit RNR packet TXCOUNT correctly transmitted frames TXQOVF LW frame discarded if output queue is too small Chapter 12 LAWNII Error Counters 49 Chapter 13 Tips to Using the LAWNII for Indoor Applications Like every radio LAWNII needs to have a good radio link to achieve its optimum performance A good radio link means an unobstructed path between the antennas of the receiver and transmitter Unfortunately when a radio is used indoors it is very difficult to arrange the radio s position for an unobstructed path due to the walls fixtures shelves and furniture On the contrary we should thank these metallic obstructions for making indoor radio communication possible These metallic obstructions reflect the radio waves in every direction and eventually some p
74. pack option which will require replacements under normal use during the life of the hardware This warranty shall extend for a period of three years for Datagram LAWNII only or one year for LAWNII Plus from the date of purchase by you If you discover that the LAWNII is defective at any time during the warranty period 1 call OCI at 800 OCI LAWN and request a Return Material Authorization Number RMA Number and 2 return the defective item to OCI at 809 N Bethlehem Pike C6 Spring House PA 19477 shipping and insurance charges prepaid together with your name address telephone number RMA Number a description of the problem and a copy of your receipt showing the date of purchase and the price paid OCI will at OCI s option either 1 repair or replace the LAWNII that does not meet OCI s Limited Warranty or 2 refund the price paid These are your sole and exclusive remedies of any claim relating to the performance of the LAWNII This warranty does not apply if the LAWNII has been damaged by accident abuse misuse or misapplication or if the LAWNII has been modified or opened EXCEPT AS SPECIFICALLY PROVIDED ABOVE OCI MAKES NO OTHER WARRANTY OR REPRESENTATION OF ANY KIND EITHER EXPRESSED OR IMPLIED WITH RESPECT TO THE SOFTWARE HARDWARE DISKETTE OR DOCUMENTATION THE PRODUCTS INCLUD ING THEIR QUALITY PERFORMANCE MERCHANTABILITY OR FITNESS FOR A PARTICU LAR PURPOSE THE ENTIRE RISK AS TO THE SELECTION QUALITY RESULTS AND PER
75. quirement of the tower as follows Height of the tower height of building 66 30 so that Height of the tower 66 30 40 56 And each antenna is mounted on a 10 mast so that the actual antenna height is 66 at one end and 50 at the other If the trees between the two nodes are taller than the building you will need to add that difference to the antenna mast For instance in the above example if the building is a two story and is only 20 tall you will need to add 10 to the mast so that the roof is at least the same level as the ob struction The height of the tower for this situation is Height of the tower 66 30 30 66 So that the tower should be 66 tall and with a 10 mast on the tower At the other side the mast must be 20 tall So the actual antenna height is 76 at one end and 40 at the other Omnispread Communications Inc 56 Installation WARNING Installing the antenna near power lines is dangerous To install the LAWN II Plus system first you need to find a place to install a mast for the antenna Each year hundreds of people are killed mutilated or receive severe permanent injuries when attempting to install an antenna In many cases the victim was aware of the danger of electrocu tion but not take adequate steps to avoid the hazard For your own safety and to help you achieve a good installation please READ and FOLLOW the safety precautions below THIS MAY SAVE YOU
76. r LAWNII Plus Connect a LAWNII Plus to a PC or printer DTE LAWNII Plus Computer DB9 DB25 1 M 8 2 mmm M 3 3 nmn 2 4 oc 20 D Q__ AA A nnn nnn nnn nnn 7 6 6 IS 4 B 5 9 LAWNII Plus Computer DB9 DB9 _ _ _ _ _______ _QE____ nn nanan nnn nnn nnn ne 1 PE 2 3B 3 A m Le ies Aes 4 5 6 6 A es eie 7 B 8 9 LAWNII Plus Modem DB9 DB9 De ha aca aa e ee ee 3 Bless a ee ue 2 A ne 5 E o iU c ep 8 Bogpenni d cac cc eh 7 LAWNII Plus Modem DB9 DB25 Qinlene ceo O a ne Kee 2 td 3 ao o_O E OO ek de 7 a gg a OD tere 5 E LO E O E O nu 4 Omnispread Communications Inc 76 Connect a LAWNII Plus to a terminal LAWNII Plus Terminal DB9 DB9 2 2 A Ed 3 ad 5 _ gt A A 7 8 8 LAWNII Plus Terminal DB9 DB25 2 0Q_EE_ A BG 3 A 2 5 7 J
77. rectly and cause minimum damage to the building and radios The effectiveness of your lightning rod totally depends upon the grounding earth that the light ning rod is connected to and the quality of grounding earth completely depends upon the mois ture contents in the earth It is the conductive moisture in the earth that provides the real ground for the system The best thing you can do is to bury the earth rod into the earth as deep as you can and hopefully it will reach a stable ground water level to protect your system Or you can connect the ground wire to the sewer or water line that usually will be in contact with the ground water level at some point of the system The mast of the antenna should be connected to the earth rod via a twisted pair of 10 copper or stainless steel ground wire Please make sure that the connection of the wire to the earth rod or the sewer or water line will be free from corrosion If you like to use the lightning arrestor for the antenna you can order it from OCI along with the special cable to connect the arrestor to the antenna The basic idea behind the lightning arrestor is that when the lightning hit the antenna the lightning energy will travel down the cable at different speed between the shield and the center conductor of the cable The difference of speed will cause a big spike at the end of the cable The use of lightning protector which is installed in line with the cable will bypass the spike energy t
78. rference to and from other radio equipments that are also using the 902 928 ISM band The channel is set by the CHA command For the channel frequency please see Chapter Six Commands the User Can Modify Hardware reset The hardware reset switch resets the processor Action on hardware reset will force the LAWNII to return to command mode except if the LAWNII is in peripheral mode or if DFC is ON The software RESTART command provides a similar action No parameters are changed by a hardware reset RS 232 Interface The LAWNII is a DCE device just like a modem The Data Set Ready 6 is asserted whenever the LAWNII is powered on The LAWNII can be operated with both the hardware and software flow control The hardware flow control is operated according to the industrial standard When a device sets Data Terminal Ready 20 or Request To Send 4 false transmission of data to that device from the LAWNII over the RS 232 link will be halted The LAWNII uses Clear To Send 5 to tell the other device to stop sending data OCI connects the status of the CONNECT light at the front panel to the RS 232 Received Line Signal Detector carrier detect The hardware flow control and the software flow control can be turned on or off independently Chapter 5 Operation Requirements 31 Chapter 6 Commands the User Can Modify The LAWNII firmware has many commands Some of these commands are related to the radio or protocol an
79. rial port settings by simply a click on the new desired serial setting LAWNII Configuration Program will verify the communications to the LAWNII send the new settings to the LAWNII change the local settings to match with the new settings and issue the SAVE command to the LAWNII to store the new settings restart the LAWNII and finally verify that the LAWNII is changed to the new settings correctly Checking LAWNII Settings The LAWN Settings tab is where you can view and edit some of the basic LAWNII settings in cluding Mycall DFCN system number channel and packet format To view the current settings in the LAWNII click Find Lawn Settings button in the lower right hand side of the window This Chapter 2 Programming the LAWNII 23 will initiate the process to determine the LAWNII s setting After receiving the current settings on LAWNII you can edit the settings to fit your application To send the new settings to the LAWNII you simply press the Send Settings button located adjacent to the Find Lawn Settings button If you wish to save a set of commonly used settings to the disk you can save them as an ini file by clicking the Save Settings to File button To retrieve these settings press the Load Settings from File button Using the Terminal Emulator The terminal emulator is designed to ease the manual programming of the LAWNII with as little interference to the user as possible When you first
80. rmally floated until a node sends data to the bus Ideally the bus will be sitting at 2 5V which is halfway between the power supply and ground when it is floated However it is not always so Normally the bus voltage will be drifted toward the Vcc or ground and will reduce the noise margin of the bus One way to fix this problem is to provide a bias to the bus so that the bus will stay at the 2 5V all the time The bias resistors for the 485 bus are included in the converter One bias resistor con nects the Data to Vcc and the other connect the Data to the ground so that the bus will stay at 2 5 V Please refer to the above diagram for the location of the connection pads Applying a drop of solder to bridge the pads of Bias and Bias will connect the bus to the Vcc and Gnd respectively The followings are some notes about using the 232 485 converter A In the half duplex mode the CTS switching guard time is programmable from 10usec up to 3msec The guard time is controlled by the ASYNCPH nnn command where nnn represents any number from 1 to 999 and the unit is 16usec The actual guard time will vary depending upon the state of the firmware Please make sure that your equipment will wait for the guard time to expire before sending response data to the bus B In the 485 mode the minimum baud rate of the converter is 9600 baud Running baud rate lower than 9600 baud may cause some errors to the data C The converter is designed to be
81. rom the Settings command First enable the check box for Key visible so that the function key will become visible at the bottom of the screen Click at the Key Name column of Fl and enter cmd as the key name for Fl Click the Command column of Fl and enter CA CAC The key is the SHIFT 6 key on the keyboard Exit the Function keys Select the Communications option from the Settings command Select the port to be used to program the AWN and select the default serial port specifications to 9600 n 8 1 Exit the Communications option and click the Fl key which now should be shown with the name cmd Whenever you click the F1 key the LAWN should return the cmd to the screen You can start to program the LAWN now Chapter 2 Programming the LAWNII 21 Using the Terminal Simulation Program from Windows 95 The terminal simulation program of the Windows 95 is much simpler than the Windows 3 1 Click the Hyperterminal option from the accessaries of the main program manager Click the icon for Hyperterminal to create a new connection When the connection screen come up enter a name for this connection for example LAWNII Click the scroll bar for the Con nect using option and choose the Direct Connect to COM1 or COM2 depending upon which port the LAWNII is attached to At this moment the phone number entry will be grayed out Click the File and the
82. s EE 33 CMDTEME A O 33 CONNECT Name a A A NS ee Se S 33 CONOR AON POH 2 2 2 2 20045 des de dad da aa daras Scd e dob Pur ad hows aaa 34 PERC AO NGO BBs Seatac Tes E tu E a o ext deren NG 34 DECNAME NaMe 4 ais Seis eR nU E m SOR NERA Ee SUN TER MS 34 DIPGTBBEEAT3ONZOBE 5bddouMP A metu quus 34 DiS CONNEC ce 23 22 dh m Resa Ss Sezai OE Rude UNDIS m Oh WE ee Se Ore es Se ode Oo er Sei TR IR UR RR 34 DISPLAY OPpUlLON 4mm as ee we Soe ee ee Se a ws Sade ees DNUS S 34 ECHO VON OEE tdt td dat ta tdt ida as 35 PECES A SS ST P WEIN NN NE Ns 35 A O Dela Nas do 35 IPIE PD t Motu A uet Debt crt dett 35 MESES a A ii a s 35 MYCALD AM sute yeh b A ON D S S PE EP ST CE SS 35 PACLEN Me rie auda ded AMT foe qp ded ais ota de des a duci ends c aee d deed dos Maa rg s 36 pACITME AFTER N and PACTIME EVERYONE Quad ux 36 PARTI 2535 dns beca a d ios haic du dpt auda a ista Ree 36 RESENDOS Thes v xcci oops dog Pat ed US DIS ed s Pu Sd d p deg idees 37 RESET percal 00 doy A Bw ad Aa da 37 A tun e tud ae Me COVERY E tel E quu dun E UO O ur 37 RETRY qiios a NA dd ta 37 SAVE a aE E SS SOS ay STAMO rbaa es gla O O RA 37 E SA EE EE 38 TAME e al is sa a aa a a 38 PRANSPAREN T 2 4959 is IS A AE IS ad ds 38 RECON ON OFF E aces wired das edad da ds De d am dd dis MIS d x 38 dS A iS EE 38 TAE LOW ONO a a A xe 38 SEE DOW SONO A IA IS Santis Ais 38 Chapter 7 Datagram CommandS ecmmmocncnccccnnnnnneconannononnnnanonennnananorrnnannrrnnananorranannancrzzaaas OO TOR EO
83. s from the earth This is because most foliages are in up and down position so that horizontal wave has a better chance to pass through and the horizontal polarization also has a narrow beamwidth that will pick up less reflection from the earth If you have to mount two Yagi antenna on the same mast you will need to space them out so that there is at least 10 between the two antennas Also you should use different polarization for them to reduce the cross coupling between the antennas Vertical Polarized Horizontal Yagi Polarized Yagi Omnidirectional Horizontal Antenna Polarized Yagi Above Examples of incorrect polarizations of antennas Omnispread Communications Inc 64 Correct Polarizations Vertical Polarized Vertical Polarized i o Horizontal Horizontal Polarized Yagi Polarized Yagi Omnidirectional Vertical Polarized Antenna Yagi Chapter 19 Polarization Selection 65 Chapter 20 Lightning protection The mast of the antenna must be directly grounded to the earth so that it works as the lightning rod for your system A lightning rod is a sharp metallic object that diffuse the static charges accu mulated on the building or structure into the air As a result the static charges on the building are greatly reduced as are the chances of getting hit by lightning Even if in the unfortunate event that the lightning does hit the energy released by the lightning hopefully will be channeled to the earth di
84. selection ceres esee ee eeen nennen nnnm nnus 64 COMECE Polafizd OS o yere tatus eter dee Cun e e eoa ete po vu cat 65 Chapter 20 Lightning protection 1 ee eeeeeiee er er rn enn aannn naa naa anna anna nana uon 66 Chapter 21 The MastSelecHon iiooeccaiesoice isaac aran anno naaa aaa cana SR cbc dada 67 Chapter 22 Installing the LAWNII Plus system sssssssnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnn nnmnnn na 68 Bench FUNCIONA LON iaa 68 az z a utol puer Ee 68 Installing the aluminum raincoat for LAWNII seeeeeeeeennnnnnnnn 68 Installing the Cold Shrink Tape ooocooccccconococonocononnnnnnonnnnnnnnconanononnnrnnn o rn nn ncnnn rn rn nrnanannnnnnn 69 Installation Tips and WamMingQS cccccccccnnnnnoccnnconononnnononnnnnnnnonnnrnnnnnnnnn on nnnnnannornnrnnnnannnccnnns 70 Chapter 23 System Check and Functional Test niens 72 LEDSAtUS CNE ES 72 COMME EH A dl ce 73 Dieta tas oen O AT 73 More on the antenna alignment cccccnocccccccncconnnncnannnnnnnnnnnn cnn enne nnne nnn nnn 73 Heroica du OE EC n 74 One to one TIG BWOTR soe or roster pe cota tente ada vua ree bees eens per xe SE reg 74 M ltdrop hebtWOfk 2 d e E et a lia 75 Chapter 24 Making RS 232 Cables for LAWNII Plus 1er 76 Connect a LAWNII Plus to a PC or printer DTE occcccccccccnnncnonononnnoncnononananana conos 76 Conne
85. ss powerful the antenna becomes How much can you tilt Generally speaking a tilt angle of 30 degree could cost you at least 6db on your path loss that is equal to losing half of the coverage distance The mounting bracket of the 8 5db Yagi antenna provided by OCI allows the user to tilt the antenna easily It has four notches for the rear mounting holes Each notch represents a 10 degrees tilt Loopback Test The loopback test is an optional test that will give you confidence that the radio is ready to work for you in the field It does not take much time to do the test after you have done the path robust ness test One to one network Assuming that you set the LAWNII Plus up by following the one to one example in Chapter 10 Examples and you have the terminal connected to the HOST Omnispread Communications Inc 74 First get into the command mode and issue the following loopback command CO HOST VIA REMOTE After the connection has been established by checking status of the Connect light or issuing a COnnect command to the firmware to confirm the connection you may then switch to the transparent mode and type any key to the keyboard and see it echoed back through the radio immediately Every time you hit a key the Transmit and Receive Light should only flash once If it flashes more than once the radio path might not be robust After you are satisfied with the test you may simply reset the system by
86. state of the current connection If a name is supplied then a connection to that name is attempted For example C LASER will cause the LAWNII to connect to the printer LAWNII named LASER Or C will cause the LAWNII to report the current connection status for example CONNECTED TO JIM or CONNECT IN PROGRESS Chapter 6 Commands the User Can Modify 33 CONOK ON OFF Default ON If Conok is on then other LAWNIIs are allowed to connect to this LAWNII If conok is off then LAWNIIs attempting to connect to this LAWNII will get a busy message on a connect attempt DFC ON OFF Default Off DFC ON turns on default connect mode and immediately enters the transparent mode DFCNAME name Default IPRNTR Sets the default connect to name DIGIPEAT ON OFF Default ON If Digipeat is set ON it will allow the LAWNII to act as a VIA for other LAWNIIS DISCONNECT Disconnects from the current connection if a connection exists If all the data has not been sent then the remaining data will be lost DISPLAY option Shows the current status of all commands including those which the user cannot modify Several dasses of display are possible Option Description ASYNC display async port parameters CHARACTE display special characters ID display ID parameters LINK display link parameters MONITOR display monitor parameters TIMING display timing parameters HEALTH display health parameters Please n
87. t mode LCALLS SLAVE listen only for packets to slaves TRANS go to transparent mode The slaves may use independent names but must have a common broadcast name that is used for LCALLS For example all the slaves can be named differently with the MYCALL command but with the same broadcast name given by LCALLS command The benefit of doing this way is that it allows you to address each slave individually from the master by using the connect oriented service during the debugging or system functional test while also allowing you to return to the desired multidrop network immediately after the tests is done If all the slaves are named identi cally by the MYCALL command you will not be able to address each one individually to perform a connect test or a loopback test to each one The connect oriented service can only be done when each radio has an unique name In the master to slave network the user must provide the specific address for the equipment that the slave is attached to along with the data sending to that equipment All slaves will receive the same address code and data from the master and pass them on to the equipment The equipment will respond only when the address code in the data packet matches its own address The user needs to provide his own protocol for polling and resend to ensure the data integrity Chapter 10 Examples 45 RS 232 cable replacing one to one This is an example to use a pair of LAWNIIs to replace a singl
88. ta packet from the MASTER the same data packet will be rebroadcasted by RSLAVE immediately The rebroadcasted message will only be received by SLAVE As a result the SLAVE will receive the same message twice The response packets from the slave can be directly received by the MASTER directly or repeated through the RMASTER As a result the MASTER will receive four responses The multiple response might cause air traffic congestion if the system is busy sending and receiving data all the time One way to reduce the traffic congestion of the airway is for the SLAVE to ignore the second data packet Omnispread Communications Inc 84 and only send one response back to the MASTER Doubling the message from different paths will greatly reduce the impact of multipath and im prove the quality of signal If the MASTER has trouble to communicate directly with the SLAVE at one area you can install the RSLAVE and RMASTER in a favorable position so that the repeaters can talk to both the MASTER and SLAVE easily If you still have another trouble area you can even add another repeater set to cover that trouble area however the MASTER will now receive nine responses The following example show you how to use two repeater sets to cover two trouble areas MASTER RM1 RSL2 RM2 RSL2 SLAVE MYCALLM 1 M2 S2 M3 S3 S1 DFCN M1 M2 S2 M3 S3 S1 LCALL M1M2 M3 M1 S1 M2 S2 51 52 53 UNPROTOS1 M2 S2 M3 S3 M1 LAWNG ON ON ON ON ON ON TRANSGON ON ON ON ON ON RM2 R
89. th Indicators such as the num ber of packets received and the number of bad packets From this information you can calculate the bit error rate In conclusion the command mode is the operating mode that you use to communicate with the microprocessor of the LAWNI The command mode is used normally only during the initial configuration and testing Once it is configured correctly the LAVW N should then be switched to the transparent mode to send and receive data either automatically or manually If the LAWNII is programmed as a peripheral device as in DFC mode it will be automatically switched to the transparent mode when it is powered up Otherwise the LAW N will stay in the command mode after the power up and you will need to issue a command to switch it to the transparent mode manually Using the Terminal Simulation Program from Windows 3 1 Since the lt Ctrl gt C is a special command COPY for Windows 3 1 the Windows 3 1 will not send it out to the serial port when you type lt CtrIC The only way to send the lt Ctri gt C to the serial port is by using the special Function Key feature of the Windows 3 1 program To do this first select the Terminal Preference option from the Settings command The menu of the terminal preference should show up Make sure that the CR gt CR LF option for both the Inbound and Outbound are unchecked Exit the Terminal Preference option Select the Function Keys option f
90. the broadcast mode You may use up to 7 repeaters to extend the range in the connected mode by specifying the repeaters name in the connect path The repeater can be any other LAWNII that is located be tween you and your destination You do not need to dedicate a LAWNII solely as a repeater In the broadcast mode you will need to dedicate a repeater set to extend your coverage There are two ways to use a repeater set in a broadcast network either serially or parallel please see Chapter Twenty Six Using Repeater for the Broadcast Mode at the end of the manual about the repeater set in a broadcast network The repeater set is the best way to extend your network In a serial repeater set you do not need to modify your polling software except allowing more delay for responses from your slave Flow control Normally an RS 485 network is operated without flow control So if you use LAWNII in a multidrop network you will not need to enable the flow control at all until your data is moved too fast for the LAWNII and it causes data overrun problem You must then turn on the software flow control to prevent this problem If you use the LAWNII as an one to one network then you must enable the flow control either software or hardware flow control Without the flow control the data overrun can occur easily when the radio needs to resend packets while new data keeps arriving LAWNII has an internal 2K buffer that is quite large for most serial
91. ther screen formatting LCALLS nl n2 Sets the list of destination names that will be monitored TRANSGRA ON OFF Default OFF Set ON to receive Datagram in transparent mode UNPROTO name Default CQ Name of the destination LAWNII or LAWNIIs default is CQ Chapter 8 485 Option Command ASYNCPH n Default 76 Sets the hang on time of the output data to the 485 bus The unit is 16usec and the default is about 1msec Please avoid sending data to the bus before the hang on time expires Chapter 6 Commands the User Can Modify 39 Chapter 9 Messages from the LAWNII Command mode messages bbRAM loaded with defaults This message appears along with the sign on message if the battery backup RAM checksum verification fails at power up time This can indicate a hardware problem cmd This is the command prompt It appears in response to a carriage return if in command mode or a break if in transparent mode was The current state of a command is reported when a parameter is changed too many packets outstanding This will appear if the outgoing packet buffer is full and you attempt to go from command mode to transparent mode It usually indicates a failure in the link between the sender and the receiver Command mode error messages bad The command entered is correct but the rest of the command line is incorrect call The name entered for MYCALL or DFCNAME is invalid EH An invalid comman
92. tion at a time In the broadcast service the LAWNII operates in the unconnected operation In this operation there are only two kinds of LAWNII in the system the master and the slaves In most cases all the slaves have exactly the same settings There will be no virtual connection between the master and the slaves When the master broadcasts a message all the slaves will receive the same message while when a slave broadcasts a message only the master will receive it The slaves usually do not communicate with each other In order for two LAWNIIs to talk to each other they must have the same radio channel and the same system number and each LAWNII must have an unique name unless it is used as a slave in the broadcast mode Please also note that every LAWNII comes out of the factory set to have a default name IPRNTR and set at the default 9600 N 8 1 You must assign a new name to every LAWNII before using it Never use a LAWNII with the default name which indicates that the LAWNII is un programed and is not ready to work for you Omnispread Communications Inc 26 Chapter 4 Operation Modes By the nature of the input and output at the RS 232 port the LAWNII is operated in two modes They are the command mode and the transparent mode By the function of the LAWNII s firm ware the LAWNII can be operated in a few modes such as the peripheral mode DFC mode and Datagram mode In the command mode the input and output at the RS 2
93. to install the radio outdoor with the antenna you should install an aluminum Raincoat provided by OCI to keep the radio away from the direct exposure to the weather Installing the aluminum raincoat for LAWNII The LAWNII is housed in an NEMAAX enclosure This kind of enclosure is weatherproof but not waterproof which means that it can be used in an outdoor environment but not to be submerged into water The NEMA4X enclosure is a solid box for any electronics equipment to be used out doors Nevertheless the moisture can eventually creep inside the box through the breathing process which occurs naturally due to the thermal expansion and contraction cycles The moisture problem can be worse if the box stays wet for a long period of time In order to prevent the moisture problem OCI supplies an aluminum raincoat 210 ARO with each LAWNII when it is to be installed in an outdoor environment This enclosure will reduce the thermal stress to the LAWNII enclosure greatly and also keep the LAWNII dry most of the time As a result the operating life of the LAWNII is significantly increased Omnispread Communications Inc 68 It is strongly recommended that the LAWNII is installed with the aluminum raincoat or at a place that is not directly exposed to the weather OCI offers an extended warranty of three years for the LAWNII that is installed this way The warranty for a LAWNII that is installed outdoors and directly exposed to the weat
94. to secure the RS 232 cable to the mast and along the way to the entering hole of the building so that it will not hang loose You can now install the mounting bracket for the mast After done that carefully take the antenna radio and mast assembly to mounting bracket and insert Make sure that the antennas are point ing to each other by using binoculars or other means If it is possible please keep the antenna and the path of the antenna from any metallic object like power lines water tanks or lamp posts as far as possible Chapter 22 Installing the LAWNII Plus System 71 Chapter 23 System Check and Functional Test After the system is installed you need to do the following tests to make sure that the installation is successful LED status check Plug the power cube to the wall and connect the DC plug to the power input socket of the cable Make sure that the power LED is ON Please get yourself familiar with these LED s They offer a great help to you to understand the status of the LAWNII Plus both in normal operation or during troubleshooting Normally the only light that will stay on solid is the power LED During the power up self check the connect LED and transmit LED should both flash and then both will go off This indicates that the microprocessor has finished the self check and the radio is ready to send and receive data for you The transmit LED will come on when the radio is sending data to the air and the recei
95. turning the power switch off and then back on The radio system should be ready to work for you when it is powered up again Multidrop network If you program all the slaves to have the same identical settings it can be inconvenient for you to perform an one to one test from the master to each individual slave You will need to turn the power of those slaves not under the test off and test one slave at a time This might cause some problem especially when the slaves are scattered around in a large area One way to solve this problem is to program each slave differently so that each slave has an unique name but still has the same common broadcast name so that they can still be operated in a multidrop network In this way you can identify and address each slave individually and they can still work in a unconnected broadcast network receiving the same unconnected packet from the master For example if you have a system with one master and two remote slaves You can program them as follows Remote 1 Remote F2 Host MYC SLAVE1 MYC SLAVE2 MYC MASTER DFCN SLAVE1 DFCN SLAVE2 DFCN MASTER LCALLS SLAVE LCALLS SLAVE LCALLS MASTER UNPROTO MASTER UNPROTO MASTER UNPROTO SLAVE LAWNGRA ON LAWNGRA ON LAWNGRA ON TRANSGRA ON TRANSGRA ON TRANSGRA ON TRANS TRANS TRANS Now you can perform the loopback test to each slave individually and still run the multidrop network Chapter 23 System Check and Functional Test 75 Chapter 24 Making RS 232 Cables fo
96. ust be properly secured by guy wires A profes sional help is strongly recommended Chimney Mount The chimney is usually a good place for the mast if it can support the mast and antenna in high winds Do not use a chimney that has loose bricks or mortar Secure the mast with at least two heavy duty strap clamp brackets Place the two brackets away from each other as far as possible for a maximum strength Chapter 18 Support Selection 63 Chapter 19 Polarization selection The Yagi antenna can be used in either vertical or horizontal polarization However the horizontal polarization will accumulate more snow and ice during the winter and lose more signals Normally a vertical polarization should be the first choice In the vertical polar ization all the ribs of the antenna are pointing up and down while they are pointing left and right in the horizontal polarization You must operate all the antennas in the same way Mixed polariza tion might reduce the range significantly If you are using Yagi and omnidirectional antennas at the same system please remember that the omnidirectional antenna is vertically polarized and should be installed at the highest point of the structure Please see the following figures for your polariza tion selection The polarization of antenna does not affect the range however the horizontal polarization is found a better choice if there are foliages between the antenna or if there are more reflection
97. ve LED will come on when it receives data from the air Please note that you may or may not receive data at the serial port of the LAWNII Plus even though the receive LED is actively blinking You will receive the data at the serial port only when your radio has the same name and system number as the data packet it received The connect LED may or may not come on during the data transmission The status of the con nect light depends upon the operating mode of the radio The connect LED will not come on at all if it is operated in the broadcast mode It will only stay on in the connect mode when it is actively sending and or receiving data The connect LED will go off if the serial port has been idle for a period longer than the connection time out It will come on immediately when the port is busy again If the connect LED comes on first and stays on it indicates that the microprocessor does not boot up properly It could be caused by a defective processor serial port driver or power supply You may use a multimeter or oscilloscope to measure the power supply input If the voltage drops below 6V standard LAWNII Plus or 10V LAWNII Plus with 12V option then the microprocessor will have trouble to boot up correctly If the power supply voltage is normal you will need to contact OCI to get your LAWNII Plus repaired If the LAWNII Plus is booted up successfully you will need to make sure that the antenna Is aligned properly before performing oth
98. will need to implement the parallel repeater set to cover more area You have to make the decision by judging the circumstance or by simply trying out both ways to determine which is the better solution Serial repeater set In the serial repeater set mode you simply reduce the coverage distance by half for each leg of the link and install the repeater set at approximately the half way between the host and remote units You may use different RF channel for each leg of the communication path If only one channel is available you then have to use different name for the repeater set For example the distance between MASTER and SLAVE is becoming too great and you need to use serial repeater set you will do the following A Using different RF channel SLAVE MASTER 2 S sse poss Omnispread Communications Inc 82 Program the radios as follows MASTER RSLAVE MYC MASTER SLAVE DFCN MASTER SLAVE LCALL MASTER SLAVE UNPROTO SLAVE MASTER CHA 1 1 LAWNGRAM ON ON TRANSGRAM ON ON RMASTER MASTER MASTER MASTER SLAVE 3 ON ON SLAVE SLAVE SLAVE SLAVE MASTER 3 ON ON Please note that a null modem cable is used between RSLAVE and RMASTER In the serial repeater set mode the distance of each leg of the radio path is half of the distance without the repeater set As a result the multipath signal has less effect If you only have one channel available then you have to use a different name for the system such
99. y are always matched over the air regardless the setting at its serial port You may use repeaters with the DFC mode by specifying the repeaters name with the DFCN command For example DFCN REMOTE VIA MARY JOHN NANCY will use MARY JOHN and NANCY as the repeaters to the REMOTE The sequence of the repeater must be exactly the same as their physically location in the repeater path Omnispread Communications Inc 46 Chapter 11 Application Notes Radio propagation investigation Before you install a LAWNII to a location permanently you must make sure that it is located at a radio friendly spot This is especially true for long range outdoor communications that use Yagi antennas You must make sure that the antennas are aiming to each other properly To find out the path conditions of your radio link you must send the FCC command to one of the LAWNII to turn on the transmitter and observe the Received Traffic LED on the other side of the link For example you will send the FCC command to the master LAWNII Plus of a multidrop system and then check the Traffic light of each slave LAWNII Plus at the remote end Each slave must have a solid traffic light to ensure that the link is solid Flicking Traffic light indicates the presence of nulls or a weak signal You may adjust the aiming of the antenna at the remote end to locate the best signal Using repeater set to extend coverage range in

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