Chapter 3: Connection Methods, Attributes and Configurable Features
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Table 3.2 describes this method’s configurable items for each serial port.
Raw TCP server
The raw TCP server connection method allows a remote client to make a TCP socket connection to
a serial port on the ESP-4 MI hub and then transmit/receive data using standard TCP. The remote
client initiates the TCP session, using a predefined IP port number.
When this method is enabled, the TCP server will accept a connection from any valid remote IP
address. There is no filtering of remote addresses. When a remote raw TCP client attempts to
establish a connection, the raw TCP server will accept the connection only if the port is not already
open and in use by any connection method, including an existing raw TCP server connection on
that port. If the port is currently in use, the connection request will be rejected.
The TCP session will remain active until the remote client closes the TCP socket, the TCP
connection is broken or the inactivity time-out (if enabled) occurs.
Table 3.2: Telnet Server Connection Method Configurable Items
Item
Description
Enable/
disable
Enables or disables the Telnet server connection method on the port. This method cannot be
enabled if the raw TCP client connection method is already enabled for the port.
The default value is disabled.
Local IP port
number
Specifies the IP port number on which the Telnet server will listen. This value cannot conflict
with the port numbers specified for other enabled connection methods on either port. Valid
values are 1024-65535.
The default value is 3001 for port 1, 3002 for port 2, 3003 for port 3 and 3004 for port 4.
Inactivity time-
out
Specifies the length of time before the Telnet session 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 Telnet session will be disconnected if there is no
activity for a period of 60 seconds.
The default value is 0 (disabled).
Serial
buffering
Specifies the length of time accumulated serial data should be buffered before being sent
across the network to the Telnet client. Valid values are 0-65535 hundredths of a second. A 0
value indicates that data will be sent as soon as it is available.
For example, a value of 100 indicates that once serial data is received, it will remain buffered
up to 1 second (100 hundredths of a second), at which time all data will be sent.
If the buffer becomes half full, the time is ignored and the data is sent.
The default value is 0 (send immediately).