Digi Connect SP User Manual page 49

Basic serial settings
When you select a port profile, the profile settings appear. Choose the appropriate features for your environment.
Here are brief descriptions of the fields in the Basic Serial Settings; see the online help for detailed information about
each setting.
•
The Description field specifies an optional character string for the port that you can use to identify the device
connected to the port.
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Basic Serial Settings include Baud Rate, Data Bits, Parity, Stop Bits, and Flow Control. The basic serial port
settings must match the serial settings of the connected device. If you do not know these settings, consult the
documentation that came with your serial device. These serial settings may be documented as 9600 8N1, which
means that the device is using a baud rate of 9600 bits per second, 8 data bits, no parity, and 1 stop bit.
When using RealPort (COM port redirection) or RFC 2217, these settings are supplied by applications running on
the computer or server, and the default values on the Digi device do not need to be changed.
Multiple Electrical Interface (MEI) Serial Settings
For Digi devices with Multiple Electrical Interface (MEI) switch-setting capability, these settings configure MEI settings
on a per-port basis, and display the current MEI settings for the port. MEI settings include the type of electrical
interface (EIA-232 or EIA-485), the number of differential wires used for communication, and whether termination
and biasing resistors are used.
•
EIA-232: Sets the electrical interface for the serial port to EIA-232. This is the default setting. This interface uses
independent wires to transmit and receive data, which allows data to be sent and received between devices
simultaneously.
•
EIA-422/EIA-485: The serial port uses electrical interface EIA-485. You can use this mode for EIA-422 connections.
This interface uses two wires to both transmit and receive data. This interface also allows for multiple
transmitters and receivers to be easily connected together.
For EIA-485 mode, there are several additional settings:
2 wires | 4 wires: Selects the number of differential wires used for communication and implicitly determines

the duplex of the connection.
2 wires: The serial port operates in two-wire mode. This mode is a half-duplex connection with shared
transmit and receive wires.
4 wires: The serial port operates in four-wire mode. This mode is a full-duplex connection with independent
transmit and receive pairs.
The default is 4 wires.
Enable termination: Determines whether termination and biasing resistors are used across the lines. If

enabled, termination and biasing resistors are enabled across the lines. Termination should be enabled if
terminal/server port is an endpoint node of the 485 network. Biasing should be used in at least one unit in a
two-wire environment. If disabled, termination and biasing resistors are disabled across the lines. The default
is disabled.
Advanced serial settings
The advanced serial settings further define the serial interface, including whether port buffering (also known as port
logging), RTS Toggle, and RCI over Serial are enabled as general serial interface options. You can also define how
specific aspects of TCP and UDP serial communications should operate, including timeouts and whether a socket ID
is sent.
Digi Connect Family and ConnectPort TS Family User Guide 49