User Guide

Data Communication and Host Modes

Rev 3.0B Feb.08 70

TheTCPsessionwillbeterminatedifnodataistransmittedor

receivedfortheti me intervalspecifiedinTCPTandTCPS.

TCPTisthenumberofminutes(TCPS=0)orseconds(TCPS=1)

usedforthisidletime‐out.

Caution: TCPT should never be 0 when using the TCP mode. A

broken TCP session can result in the modem being left with a TCP

half-open connection that can only be terminated with a reset.

TCP Auto Answer

TCPautoanswer(S0=1|2 )alsoallowsaTCPconnection

requesttobe“answered”whenthemodemisidle,notina

datasession.TheTCPconnectionrequestʹsdestinationport

hastomatchthemodemʹsdeviceport.

Note: UDP auto answer may also be set simultaneously with TCP

auto answer. Then, when in the idle state, the modem will accept

either a TCP connection request or UDP incoming packet, and enter a

TCP or UDP session as appropriate.

Hybrid Modes

Hybridmodesaresupportedmainlyforlegacyimplementa‐

tions.Someprevioushybridmodes(MD=5,6)arenolonger

implementedasspecial,uniquemodes.NowthatUDPauto

answer(UDPHalf‐open,S82=2)canbeenabledinconjunction

withUDPPADmode(MD3),effectivelythisisthesameas

MD5andMD6previouslyaccomplished.SettingMD5and

MD6arestill

supported,butnotrecommended.

AT Command Hybrid Mod

(MD5)

Hybrid Mode2

(MD6)

3 3

S82

2 2

1 1

*UDPLAST

0 1