Cooper Bussmann BU-945U-E 802.11 DSSS user manual 3A1582Rev1.6

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Cooper Bussmann Wireless Ethernet & Device Server BU-945U-E 802.11 DSSS User Manual

Modbus RTU (serial) Master functionality is achieved by combining the Modbus TCP Client (Master) and Modbus TCP to RTU Gateway. Simply specify a Modbus TCP Client (Master) connection to a Modbus TCP Server where the server is the address of any BU-945U-E with Modbus TCP to RTU Gateway enabled. Care should be taken to ensure that the Device ID (i.e., Modbus Address) of the serial device is different to the Device ID of the onboard Modbus TCP Server of the BU-945U-E that the serial device is connected to.

The BU-945U-E provides a configurable option to automatically reset the value of the onboard I/O registers to zero in the event of a communications failure. If a valid Modbus transaction directed to/from a given register has not been completed for longer than a configurable timeout, then the value of that register will be reset to zero.

An example of the Modbus functionality of the BU-945U-E is illustrated below. In this example the status of the onboard digital input at C will be reflected at the onboard digital output at B. Also, 8 single bit registers from Modbus serial device D will be transferred to A.

Unit B is configured with Modbus TCP Server enabled and Device ID = 1, Unit C is configured as shown above.

•The first will write the register 4300 (Local Digital Input) to server IP address 192.168.0.200 (Unit B), Device ID #1, register 4320 (Local Digital output).

•The second mapping shows a Modbus read command of 8 Discretes starting at register 1 (Destination Reg) on Device ID #6 connected to IP address 192.168.0.123 (it self) and store the values at register #1 locally.

•The third mapping shows the Modbus write command (Write Coils) which is writing the local 8 I/O’s starting at register 1 across to Server IP address 192.168.0.200, Device ID #5, destination reg #1.

The configuration of unit B is shown below (accessible via the “I/O Transfer” configuration page). It can be seen that Modbus TCP Client has been enabled with a 500msec scan rate, meaning that there will be a 500msec delay between each of the mappings directed at any server. The “Reset Registers on Comms Fail” option is enabled with a timeout of 60 seconds, indicating that any of the registers at unit B will be reset if a successful Modbus transaction involving that register has not been executed in the last 60 seconds. The Modbus TCP to RTU Gateway at B must also be enabled (see section “3.13.3 Modbus TCP to RTU Gateway”) to allow Modbus communications with the serial device A.

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3A1582Rev1.6

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Contents Read Retain Phone 800 a.m 500 p.m. Central, M-F 636 Fax 636 Cooper Bussmann Application EngineeringFCC Notice Cooper Bussmann Important NoticeGNU Free Documentation License Contents Network Topology BU-945U-E 802.11 630mW max powerAccess Point vs Client 3A1582Rev1.6 Bridge vs. Router Getting Started Quickly Antenna Installation GeneralLine-of-sight installations Bench test and Demo System SetupPlant and Factory Installations AntennasInstallation tips Omni-directional AntennasDirectional Antennas Power SupplySerial Connections RS232 Serial PortDB9 Connector Pinouts RS485 Serial Port3A1582Rev1.6 Discrete Digital Input/Output Start-up 802.11 900 MHz Channels Selecting a ChannelLED Indication 3A1582Rev1.6 Radio Throughput Data Throughput Based on Repeater HopsAccessing Configuration for the First Time Configuring the Unit for the First TimeDefault Configuration Method 1 Set PC to same network as BU-945U-E Power up the BU-945U-E moduleEnter the username user and default password user For local addresses3A1582Rev1.6 Quick Start Configuration Quick StartNetwork Configuration Configured Essid of the client Dhcp Server Configuration, Default is uncheckedWireless ports will have the same IP address Save Changes and ResetSecurity Menu Encryption keys must not be all zeros, i.e3A1582Rev1.6 Transparent Bridge Operation Radio ConfigurationNormal Operation Router OperationDrop back to non-bursting mode Bands Default is AutoSignal quality, etc Access pointDefault distance is 20km Dhcp Client ConfigurationRadio Mode BU-945U-E Only Supports the 802.11 Standard Channel SelectionSpanning Tree Algorithm / Redundancy Dhcp Server ConfigurationDNS Server Configuration Multiple AP Repeater Mesh Network 3A1582Rev1.6 Example Extending range using WDS Site B WDS ConfigurationExample Roaming with WDS Access Points Example Adding Redundancy3A1582Rev1.6 Example WDS Routed Network Mouse, to highlight the entire row STP Routing RulesWDS Connections Information at a later time Wireless Message FilteringSpecifies a destination host 3A1582Rev1.6 Utilize the radio link. All other devices are blocked MAC Address Filter ConfigurationIP Address Filter Configuration ARP Filter Configuration Serial Port Configuration RS-232 PPP ServerSerial Gateway Server/Client/Multicast Serial Gateway Modbus Modbus RTU to TCPModbus TCP to RTU Gateway Serial MenuMulticast Pipe Manager Multicast Group IP Address Digital Input/OutputPort on the Client, i.e., Scada, DCS, etc To be the same on all communicating Multicast devicesModbus I/O Transfer 3A1582Rev1.6 Modbus TCP Configuration on I/O Transfer Menu Module Information Webpage Fields Module Information ConfigurationModbus TCP Client Mappings on I/O Transfer Menu Remote Configuration System ToolsExtending a Wired Network Configuration ExamplesSetting a BU-945U-E to Factory Default Settings LAN B Configuration Client 1 ConfigurationClient 2 Configuration Extending Range of a Network with a Repeater Hop Access Point ConfigurationClient Configuration LED Indicator Condition Meaning Diagnostics ChartBoot Status LED Indication during Start-up RED ContinuouslyConnectivity Parameters Diagnostic Information AvailableConnectivity Site SurveyStatistics Network Traffic AnalysisConnection Information Internal Diagnostic Modbus Registers9999 Both Reset module enter Ffff to reset module 5014 STA OnlyStatistic Registers Ping Testing Radio PathsUtilities 3A1582Rev1.6 Ipconfig ArpRoute Radio Transceiver Power SupplyGeneral Serial PortsSystem Parameters Input / Output statusWeb-Based Upgrade Appendix a Firmware UpgradesCSMA/CD ACKCSMA/CA DhcpISN IeeeIPX-SPX NIC SNRNAT SSLWAN VoIPVPN WEPDBm to mW Conversion Iperf Applications InstallationMaterials 3A1582Rev1.6 JPerf Application 3A1582Rev1.6 Preamble Terms and Conditions3A1582Rev1.6 No Warranty 3A1582Rev1.6 Customer Assistance
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