PEB 2091
PEF 2091
Operational Description
4.3.1
Complete Activation Initiated by LT
Figure 53 depicts the procedure if the activation has been initiated by the exchange side.
If activation is initiated with the C/I code AR, as shown in Figure 53, activation will fail if
the signal SN3 hasn’t been correctly received within 15 seconds. In this case the LT side
will indicate the C/I code EI3 instead of UAI and the device should be reset (see "LT
Modes State Diagram", page 147). In normal LT-NT configurations these 15 seconds are
much longer than average activation time which lies between 1-7 seconds, depending
on line characteristics, i.e. if this timer expires it is a strong indication for an error
condition.
In some configurations, however, e.g. a line with several repeaters, this timer could
expire under normal activation condition. For such configurations the IEC-Q provides the
C/I command ARX which can be used instead of the command AR for activation. If
activated with the ARX command the IEC-Q will continue the activation procedure, even
if the 15 seconds timer has expired.
S/T
IOM R -2
U-Reference Point
IOM R -2
INFO 0
INFO 0
DC
DI
SL0
SN0
DC
DI
AR
TL
PU
DC
TN
AR
SN1
SN0
SL1
SL2 act = 0 dea = 1 uoa = 1
ARM
UAI
SN2
SN3 act = 0 (sai = 0)
AR
AR
INFO 2
INFO 3
INFO 4
SN3 act = 0 sai =1
SL3T act = 0 dea = 1 uoa = 1
AI
AI
SN3 act = 1 sai = 1
SL3T act = 1 dea =1 uoa =1
AI
SN3T
SL3T
R
SBCX
IEC-Q
IEC-Q
EPIC
NT
LT
ITD04241
Figure 53
Complete Activation Initiated by LT
Semiconductor Group
126
Data Sheet 01.99
INFINEON [ Infineon ]
