Port Function - Modbus
The following configuration allows either:
- the SCADAPack x70 device to connect to a Modbus RTU Client device as a Server
- Geo SCADA Expert to connect to a Modbus RTU Server device when you are using SCADAPack x70 configuration software to set up Modbus RTU Client operation.
The following two sections are displayed when you select this Port Function:

Use the combo box to specify the mode in which a port is operating. The options vary, depending on the port and device type, and can comprise a combination of the following:
- RS232 (RTS Off)
- RS232 (RTS On)
- RS232 (RTS) Keyed - this requires you to Configure Serial Multidrop Settings.
- RS232
- RS485 2 Wire
Use the combo box to specify the baud rate used for transferring data via the port.
Use the combo box to specify the number of data bits used to transmit each byte of data and the parity. The options comprise:
- 8-bit No Parity
- 8-bit Even Parity
- 8-bit Odd Parity
- 8-bit No Parity 2 Stop Bits.

Use the Addressing field to select the addressing mode for the Modbus protocol. This determines the range of station addresses. Select one of the following options:
- Standard—This is the default option. If you select this option, the valid ranges of the Modbus Station Address and the Enron Station Address fields are between 1 and 255 inclusive.
- Extended—If you select this option, the valid ranges of the Modbus Station Address and the Enron Station Address fields are between 1 and 65534 inclusive.
This property only applies when you are using the SCADAPack x70 device to connect to a Modbus RTU Client device as a Server.
Use the field to enter the Modbus Station address for Modbus communications on the serial port. The valid range for this field is dependent on the Addressing mode. The default is 1.
This property only applies when you are using the SCADAPack x70 device to connect to a Modbus RTU Client device as a Server and when you enable the Realflo Flow Computer option in the Device Configuration Options section of the Settings tab (see Configure the Device Options).
Select the check box to enable Enron Modbus on the serial port.
Clear the check box to disable Enron Modbus on the serial port.
This spin box is only available for use when the Enron Modbus check box is selected.
Use this field to define the Enron Modbus Station Address. The valid range for this field is dependent on the Addressing mode. The default is 2.
The Enron Modbus Station Address must be different to the port's Modbus Station Address.