C: Networking and Security 
EDS Device Servers User Guide  164 
 
  The EDS observes the modem control inactive setting. 
To clear out data from the serial buffers upon disconnecting, configure the EDS to flush 
serial data (see Tunnel – Disconnect Mode Page on page 66. 
Packing Mode 
Packing mode takes data from the serial port, groups it together, and sends it out to 
nodes on the network. The groupings may be configured by size or by time intervals. 
The following settings are configurable for Packing mode: 
  Enable or disable Packing mode 
  Packing mode timeout. Data that is packed for a specified period before being 
sent out. 
  Packing mode threshold. When the buffer fills to a specified amount of data and 
the timeout has not elapsed, the EDS packs the data and sends it out. 
  Send character. Similar to a start or stop character, the EDS packs data until it 
sees the send character. When it sees the send character, the EDS sends the 
packed data and the send character in the packet. 
  Trailing character. If a trailing character is defined, this character is appended to 
data put on the network immediately following the send character. 
Modem Emulation 
The EDS supports Modem Emulation mode for devices that transmit modem AT 
commands. The EDS supports two different modes: 
  Command Mode: The EDS serial ports accept modem commands that instruct 
the EDS to perform an action such as start or drop a connection. 
  Data Mode: Serial data received in the EDS serial port is sent through the active 
network connection. 
The Tunnel – Modem Emulation page lets you configure modem emulation settings for 
up to four tunnels for the EDS4100, eight for the EDS8PR, 16 for the EDS16PR, and 32 
for the EDS32PR (see Tunnel – Modem Emulation Page on page 69). Each tunnel can 
have different settings. 
Note: When the EDS serial port is in Modem Emulation mode, the serial port 
remains in Command mode until an active tunnel starts. Once an active tunnel 
starts, the serial port remains in Data mode until the connection is dropped or the 
serial port is placed in Command mode by issuing the modem command +++.