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ESP-4 MI Serial Hub Installer/User Guide
The translation sets are configured when the modem emulation connection method and outgoing
calls are enabled.
Incoming calls
When the Allow Incoming Calls option is enabled, the ESP-4 MI hub will listen on the specified
TCP port for connection requests from the network. If another call is active, an incoming
connection request will be rejected.
If the Monitor DCD option is enabled, the connection will be rejected if the control signal is
logically low. The connection will be closed if the inbound control signal changes from logically
high to low.
When a TCP connection is active, the ESP-4 MI hub will raise the outbound DTR signal to indicate
that the connection is valid (which should be seen as inbound DCD by the serial device). If the
remote end breaks the TCP connection, DTR will be lowered to indicate a Carrier Drop to the
attached serial device.
Configuration utility
The configuration utility connection method may be used on any of the ESP-4 MI serial ports.
Using the internal configuration utility, you may specify attributes of the ESP-4 MI hub and its
serial ports. This includes enabling serial port connection methods and specifying their
configurable items, plus configuring serial port attributes. The menu-based interface also allows
you to configure network parameters, download and install Flash images, reboot, reinitialize and
monitor ESP-4 MI hub status. For more information, see Chapter 5, beginning on page 35.
Table 3.9 describes this method’s configurable items for each serial port.
Serial Port Attributes
Each serial port has a set of attributes which may be modified.
NOTE:
When a port is configured for the serial port redirection connection method, the attributes are specified
within the protocol. Therefore, although you may change the attributes, any changes you specify will not
take effect.
Table 3.9: Configuration Utility Connection Method Configurable Items
Item
Description
Enable/disable
Enables or disables the configuration utility connection method on the port. The default
value is enabled for port 1 and disabled for ports 2, 3 and 4. This method cannot be
enabled if the raw TCP client connection method is already enabled on the port.
Inactivity time-out
Specifies the length of time before the configuration utility is disconnected if there is no
activity. Valid values are 0-65535 seconds. A 0 value disables the inactivity time-out.
For example, a value of 60 indicates the configuration utility will be disconnected if there
is no activity for a period of 60 seconds.
The default value is 0 (disabled).