Passthrough Setup-Port, Intermessage Time-Out

4 Creating Project Files—PLC to Devices

Saving Port 2 Configuration Information

Once you have entered all the configuration information, select Save to save the configuration to the project file. Then select Ok or press the Esc key to close the configura- tion screen.

If you have changed the configuration and have not saved it to the project file, you will be prompted to either save or dis- card the changes.

Select Revert to return to the last previously saved configu- ration without saving any changes.

4.5Passthrough Setup—Port 3

Port 3 is for passthrough communications. It allows direct communication with either the PLC on port 1 or the Sie-

mens SEAbus devices on port 2. (Passthrough communica- tions to port 2 are not available for VDEW devices.)

In passthrough mode, any messages received on port 3 of the DTU are simply “passed through” to the PLC (port 1) or devices (port 2). For example, passthrough communications enables a PC running WinPM, or other supervisory software connected to port 3 of the DTU3005, to communicate directly with the SEAbus devices connected to port 2.

You must have a PLC to Devices project file open to config- ure port 3 using the instructions in this section.

Select Port 3 (Passthrough) from the Edit menu, and the Port 3 configuration screen appears.

The first option on the configuration screen allows you to choose passthrough to port 1 or port 2. Select the appropri- ate port with the mouse, or use the Up or Down Arrow keys to highlight the selection and press Enter.

To change the intermessage time-out, select Intermes- sage Time-Outand type in the value in milliseconds, then press Enter.

The remaining configuration selections except for Intermes- sage Time-out are the same as those for port 1. Refer to Section 4.3 for instructions on these fields.

Intermessage Time-Out

The DTU3005 uses the intermessage time-out to determine when a complete message has been received on the passthrough port. Once the first character of a message has been received, if the amount of time specified by the inter- message time-out passes with no additional characters being received, the DTU3005 will consider the message to be complete and process it.

Saving Port 3 Configuration Information

Once you have entered all the configuration information, select Save to save the configuration to the project file. Then select Ok or press the Esc key to close the configura- tion screen.

If you have changed the configuration and have not saved it to the project file, you will be prompted to either save or dis- card the changes. Select Revert to return to the last previ- ously saved configuration without saving any changes.

16	Siemens Energy & Automation, Inc.