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LDM User Manual

6

Figure 1 - LDM-1 Standalone

Содержание LDM-1 plug-in

Страница 1: ...LIMITED DISTANCE MODEM USER MANUAL by MICRO AIDE CORP ...

Страница 2: ... ...

Страница 3: ...ITED DISTANCE MODEM USER MANUAL MICRO AIDE CORP 626 915 5502 support micro aide com Revised June 16 2009 A comprehensive document for the following LDM products LDM 1 standlalone LDM 1 plug in LDM 16 nest ...

Страница 4: ...t the written permission of MICRO AIDE Corporation The information in this document is subject to change without notice MICRO AIDE believes the information contained in this document to be accurate However MICRO AIDE assumes no responsibility for any errors or omissions Windows Windows 98 and Windows XP are registered trademarks of Microsoft Corporation ...

Страница 5: ... Network 10 Accessing the LDM 1 PCB 12 User Configured Settings 12 Setup 13 Rcv and Xmt Terminations AX1 and AX2 13 Enable Xmt Channel Busy Detector AX3 14 RS 232 Protective Ground AX5 14 RTS to CTS Delay SW2 14 Equalization SW3 14 Permanently Asserting the RTS 15 Installation 15 LDM 1 Standalone 15 LDM 1 Plug in 16 LDM 16 Nest 16 Attaching the Network Lines 17 Connecting to the DTE 17 CHAPTER 3 O...

Страница 6: ... Insertion 25 Jumper and Switch Locations 26 Trouble Shooting Guide 27 APPENDIX A TECHNICAL DATA LDM 1 Specifications 29 LDM 16 Specifications 30 Transmission Range Specifications 30 Recommended Equalizations Settings 31 DB 25 Connector Wiring 31 APPENDIX B TXDOT APPLICATIONS Introduction 33 Network Configurations 33 Point to Point 33 Multi Drop 34 RS 232 Cables 34 LCU to LDM 1 34 PSDM to LDM 1 34...

Страница 7: ...st a 19 rack mounted chassis that can be equipped with 1 to 16 LDM 1 plug in PCBs The LDM 1 can be thought of as a device for extending RS 232 communica tions over great distances e g thousands of feet It serves as an interface between the customer s Data Terminal Equipment DTE and data communi cations network It is designed to be compatible with four wire private line networks It can be used to f...

Страница 8: ...tor provides simple cabling to any RS 232 device Easy to activate analog and digital loop back test modes Includes transmit channel detector to avoid data transmission collisions Data contention can be resolved at the LDM 1 not at the DTE Allows full duplex operation on four wires Compact size LDM 1 standalone footprint is approximately 5 by 8 and less than 2lbs in weight LDM 16 nest can be equipp...

Страница 9: ...1 Additionally this manual is applicable to LDM 1s that have been factory reworked to the Revision D level The revision level can be found near the lower right hand corner of the LDM 1 s printed circuit board PCB TXDOT APPLICATIONS The LDM products are frequently used with MICRO AIDE s Local Control Unit LCU and other data communications devices throughout the State of Texas They have been approve...

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Страница 11: ...rear panels of the LDM 1 standalone modem The LDM 16 nest is illustrated in Figure 2 on page 7 NOTE Unless otherwise stated the term LDM 1 will refer to either version of the modem i e LDM 1 standalone and LDM 1 plug in TIP The LDM 1 must be properly configured before it can be put into operation As the setup procedure requires that the user have access to the LDM 1 PCB it is advisable that the us...

Страница 12: ...LDM User Manual 6 Figure 1 LDM 1 Standalone ...

Страница 13: ...ect the carton for damage Damage to the container should be noted Carefully remove the unit It is advisable to save all packing materials in the event the unit ever needs to be returned to MICRO AIDE Inspect each unit and PCB for any visual damage The unit should not be scratched dented or deformed in any way If it appears that the unit was dam aged in shipment the responsible carrier should be no...

Страница 14: ...em sends data via its transmit channel The basic transmit and receive methodology employed is summarized by the following rules Only one master modem can be employed per network The master modem broadcasts simultaneously to every slave modem Only one slave modem can respond to the master modem at a time It can only transmit data to the master modem i e not to another slave modem The slave DTE devi...

Страница 15: ...eferred to as Xmt and Rcv for transmit and receive respec tively Figure 3 on page 10 illustrates a typical point to point network The proper LDM 1 setup configuration for a point to point network is as fol lows The Xmt and Rcv Terminations for both modems must be set to On Since only two modems are used the RTS signal of each modem can be per manently asserted Refer to the section entitled Permane...

Страница 16: ...ipped with a slave modem The intersection of two cable segments forms a drop point A slave modem can be connected to the network at each drop point Figure 4 on page 11 illustrates a typical multi drop network The proper setup configuration for a multi drop network is as follows The Xmt and Rcv Terminations for the near and far end modems must be set to On The Xmt and Rcv Terminations for each mode...

Страница 17: ...e 30 for the given cable size and selected Baud rate The Equalization setting for the near and far end modems must be identical and set in accordance with the recommendations as listed in Table 6 on page 31 Assume a cable length equal to the near end to far end cable length The Equalization setting for a drop point modem must also be set in accor dance with the recommendations as listed in Table 6...

Страница 18: ...the nest Remove the plug in PCB by depressing the PCB retainer at the bottom front edge of the nest while rotating the PCB s card ejector upward USER CONFIGURED SETTINGS Two switch assemblies and four jumpers comprise the collection of user con figured settings Table 1 provides a brief definition of each setting Also included in Table 1 are the factory default settings CAUTION Electrostatic discha...

Страница 19: ...ther a 150Ohm On or high imped ance Off termination These jumpers are used in accordance with the fol lowing rules The AX1 Rcv and AX2 Xmt settings must always match each other Irrespective of the type of network always terminate the extreme ends of the network i e the near and far ends NOTE The factory default switch and jumper settings for AX1 through AX5 and SW2 are satisfactory for use with a ...

Страница 20: ...y leaving the jumper set to Off The LDM 1 is provided 24Vac power by a fully isolated transformer The factory default setting is Off RTS TO CTS DELAY SW2 The LDM 1 will respond to the DTE s RTS signal by asserting its CTS signal The delay from RTS to CTS is controlled by the SW2 setting The delay can be used to ensure that the transmit channel is available SW2 allows the user to select any of four...

Страница 21: ...oint networks or as a master in a multi drop network For these applications the DTE to modem cable must include a jumper between pins 4 RTS and 6 DSR at the LDM 1 end This technique will force the modem s RTS to be constantly asserted Figure 7 on page 31 illustrates the pin assignments used by the LDM 1 s DB 25 con nector INSTALLATION Physical installation of the modems and nests can be performed ...

Страница 22: ...ems are being installed it is recom mended that an empty slot be left between adjacent PCBs It may be necessary to remove the plastic shield that covers the rear connector cut outs before the PCB can be inserted Spare plastic shields should be used to cover any vacant cut outs The nest is equipped with a 120 to 24Vac transformer The 24Vac power source must be connected to each PCB Use the connecto...

Страница 23: ... down terminals at the quick disconnect plug The rear panel silk screening clearly labels each connector position The cable that connects the LDM 1 to the network should be lim ited to 100ft in length CONNECTING TO THE DTE The LDM 1 can be used with any DTE that utilizes an RS 232 interface The LDM 1 s operation is asynchronous It uses the Baud rate selected by the DTE The DTE connects to the DB 2...

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Страница 25: ... operation and the three test modes are described INDICATORS AND CONTROLS LEDS The front panel of each LDM 1 includes a set of eight multi colored LED indicators The location of each LED and the Select Mode pushbutton switch is depicted in Figure 1 on page 6 The operational mode and signal status of the modem is conveyed via the LEDs A description of each LED is listed in Table 3 on page 20 ...

Страница 26: ...ibed in the following sections Figure 6 on page 21 illustrates the signal flow applicable to each operating mode Label Name Color Description Pwr Power Red Modem has internal 5Vdc power CD Carrier Detect Green Data is present on receive channel Flashes if Test Mode C is receiving data Tst2 Tst1 Test 2 Test 1 Red Off Off Normal Mode On Off Test Mode A Off On Test Mode B On On Test Mode C CTS Clear ...

Страница 27: ... is powered up The modem will transmit receive data to from the network in accordance with the jumper and switch settings selected in the setup procedure The RS 232 interface will be fully operational The Tst2 and Tst1 LEDs are off when the modem is in Normal Mode Figure 6 Test Mode Signal Flow ...

Страница 28: ...ormal Mode Transmitted data will be returned to the source modem s receiver where it can be checked against the originally transmitted data TEST MODE B ANALOG LOOP BACK WITH DTE DATA Test Mode B loops the analog output signal of the transmit channel to the input of the receive channel The data to be transmitted is provided by the DTE The transmit and receive channels are left terminated but are di...

Страница 29: ...ent to the network In Test Mode C the Tst2 and Tst1 LEDs are both on The CD LED will flash as an indication that the test data is being received properly The RTS CTS and Xmt indicators will illuminate depend ing upon the status of the DTE interface However these signals are ignored in Test Mode C The Rcv indicator will be on Test Mode C can also be used to test the modem separately from the networ...

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Страница 31: ...ser may occasionally need to wipe dust away from the external surfaces of a unit This should be done with a clean dry cloth The mechani cal design of the housing and chassis provide the electronic assemblies with a nearly sealed environment Due to the low power requirement of each prod uct ventilation holes are not required The inside of each unit should remain clean indefinitely PCB REMOVAL AND I...

Страница 32: ...uration as necessary Install the PCB by aligning its edges with the plastic card guides secured to the top and bottom panels of the nest Push the PCB forward until it clears the retainer bar Attach any cables to their respective PCB connectors Cables are keyed so they can be inserted in only one direction Do not force a cable into a connec tor Close the front cover JUMPER AND SWITCH LOCATIONS Seve...

Страница 33: ...problems Refer to the previous Chapter 2 entitled Operation for instructions on how to use the test modes If the user is still unable to resolve the problem MICRO AIDE cus tomer service should be contacted The user will be asked to state the prob lem specify related symptoms and indicate any operations or conditions that have a bearing on the problem Symptom or Problem Resolution No indication of ...

Страница 34: ...wel comed Comments can be forwarded to the Director of Marketing MICRO AIDE Corporation Receive data contains errors Change Equalization settings to better match cable transmission properties Termination settings are incorrect should measure 150Ohm if On 40KOhm if Off Test Mode B does not echo sent charac ter Set Equalization to setting 1 minimum U character is not issued in Test Mode C Set Equali...

Страница 35: ...Red Transmit Data Red Controls External Pushbutton Switch selects operating mode Equalization Switch SW3 dual switch assembly 4 set tings to compensate for cable attenuation Internal DIP Switch SW2 Selects CTS to RTS delay of 8 16 32 or 64msec Jumper AX1 Enables Rcv channel termination of 150Ohm Jumper AX2 Enables Xmt channel termination of 150Ohm Jumper AX3 Enables Xmt channel busy detector Jumpe...

Страница 36: ...th 10 5 Height 5 4 Weight 20lbs with 8 LDM 1 plug in PCBs Mounting Mounts into std 19 equipment rack Power Voltage 120Vac 60Hz Consumption 40W with 8 LDM 1 plug in PCBs MICRO AIDE reserves the right to make changes at its sole discretion to any specification listed herein TRANSMISSION RANGE SPECIFICATIONS The specifications listed in Table 5 apply to both point to point and multi drop network conf...

Страница 37: ...om the near end master modem to far end slave modem DB 25 CONNECTOR WIRING The LDM 1 includes a DB 25 female connector It provides the RS 232 inter face to the DTE The connector is wired as illustrated in Figure 7 Baud Rate 19AWG 22AWG 24AWG 0 6 13 19 25 0 3 6 10 13 0 2 4 6 8 2400 1 2 2 3 4 1 2 2 3 4 1 2 2 3 4 4800 1 2 2 3 4 1 2 2 3 4 1 2 2 3 4 9600 1 2 2 4 1 2 2 4 1 2 2 4 4 19 000 1 2 2 1 2 2 1 2...

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Страница 39: ...figura tions Figure 3 on page 10 and Figure 4 on page 11 illustrate the basic differ ences in the two types of networks Several key points concerning each network are described in the following sections POINT TO POINT The point to point configuration is typically used when only a pair of devices need to communicate with each other A single LCU communicating with a PC would be an example Another ty...

Страница 40: ...tor is wired in accordance with DCE standards The pin assignments for the connector are illustrated in Figure 7 on page 31 The following list pro vides the user with additional information concerning cable types LCU TO LDM 1 The LCU to LDM 1 cable is a simple one to one cable with DB 25 male con nectors at each end A one to one cable can be purchased at any computer supply store It can also be eas...

Страница 41: ...he CTSCU exe test software the following items are required A Windows 3 X PC with the CTSCU exe software installed One or more LCUs installed with the TxDOT provided TMS Version 2 2 EEPROM One master LDM 1 that will be connected to the PC running CTSCU exe One slave LDM 1 for each LCU A two pair cable connecting the LDM 1s in either a point to point or multi drop network configuration One 9 pin fe...

Страница 42: ...o the RS 232 port of the LCU labeled Communications 5 Install the TMS 2 2 EEPROM into the CPU PCB of each LCU 6 Set the Unit ID of the first LCU to 1 Set the Unit ID of additional LCUs to 2 3 etc 7 Apply power to all equipment items 8 Launch the CTSCU exe software in the PC 9 Verify the test LEDs of each modem are off 10 Verify the RTS and CTS LEDs are on at the master and off at each of the slave...

Страница 43: ...hannel Number refers to the number of available comm ports in the PC Each of the LCU Numbers must correspond with one and only one LCU thumb wheel setting In the example cited above LCUs 1 3 and 4 are included in the network to be tested 3 Execute the Configure Channel Communication Parameters com mand Accept the default parameters as listed below ...

Страница 44: ... the Control Reset All LCUs command After a brief delay a message will indicate that the reset was successful 7 Execute the Control Download LCU Code to All LCUs command After a brief delay a message will indicate that the download was successful 8 Start the test at 9600Baud by executing the Begin command Highlight the command and then press the Enter key twice The test will start A display simila...

Страница 45: ...ns Test Software 39 The test will run continuously until it is stopped by pressing the Esc key The number of test blocks and errors by type will be reported Run the test in accordance with the TxDOT acceptance criteria ...

Страница 46: ...LDM User Manual 40 USER NOTES ...

Страница 47: ...CRO AIDE warrants its products to be free from defects in material and workmanship for a period of five 5 years from the date of shipment This warranty is in lieu of any other war ranty expressed or implied In no event shall MICRO AIDE be held liable for incidental or consequential damage resulting from 1 the use of any of its products or 2 any alleged breach of this warranty provision MICRO AIDE ...

Страница 48: ...MICRO AIDE CORP 685 Arrow Grand Circle Covina CA 91722 Tel 626 915 5502 Fax 626 331 9484 E mail support micro aide com ...

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