Menu
Toshiba XLTR-200 Instruction Manual
                                                                                                   | |
Contents
|
25RS485A port. And, because the RS485A port has been designated as aModbus Master, then the “Modbus Master” portion of point #5’s configurationwill be referenced by the update task, and point #5’s value will therefore alwaysbe mirroring the value of holding register #14 of remote Modbus station address#8 connected to the Modbus subnet attached to the gateway’s RS485A port.Perhaps holding register #14 of Modbus station address #8 is a monitor item,indicating the pressure in compressor tank. Whenever the tank’s pressurechanges, therefore, the value of point #5 will automatically update to reflect thenew value read from the remote device. Once the tank’s pressure reading hasbeen brought into the gateway, it can then be retrieved by any protocol (or ALLthe protocols) currently assigned to the gateway’s other communication ports.As a modification to the previous example, let’s assume this time that holdingregister #14 of Modbus remote station address #8 is the speed command of aconveyor belt. In this case, point #5 of the gateway will be mirroring the currentspeed command of the conveyor, in a similar fashion to how it previouslymirrored the compressor tank’s pressure. This time, however, the speedcommand represents something that can also be written to. Therefore, anynew data value that is written to point #5 from any other port connection willautomatically cause a “write holding register” transaction to occur on theRS485A Modbus master port, updating the value of holding register #14 onremote Modbus station #8, causing the conveyor to accelerate (or decelerate)to the new speed.Note that it is also perfectly acceptable to have a point’s “source port” assignedto “NONE”. All this means that this point will not be autonomously updated (i.e.that it will not automatically mirror anything.) In a sense, it will simply be“scratchpad memory” that the various ports and protocols can use to exchangeinformation among themselves.Although the various configuration possibilities may seem overwhelming at first,it is clear that the gateway can perform powerful and flexible routing algorithms.Through configuration experience, the “in” and “out” data flows will becomemore clear.11.4 General Configuration ProcedureNow that we have had a brief tutorial on port and point configuration, we canproceed on to how these elements fit into the overall configuration procedure.The general configuration procedure steps can be summarized as follows:1. Access the serial console configuration interface via Hyperterminal orother text-based console program.2. Assign (or enable/disable) the desired protocols and theircharacteristics to the specific communication ports.3. Perform the desired per-protocol mapping and definition assignmentsfor each point, including the name, timeout and “source port”assignments.4. Exit the serial console, which will update the gateway’s internalconfiguration file and reboot the unit. |
Related manuals for Toshiba XLTR-200
This manual is suitable for:
Product
Learn More
Legal
Copyright © 2024 OneStart. All Rights Reserved