PEF2091 Siemens Semiconductor Group, PEF2091 Datasheet - Page 168

• Manufacturer Part Number: PEF2091
• Description: ICs for Communications(ISDN Echocancellation Circuit)
• Manufacturer: Siemens Semiconductor Group

Semiconductor Group
DC
DR
EI1
INT
PU
Signals on U-Interface
The signals SNx, TN and SP transmitted on the U-interface are defined in Table 28, page
125.
The polarity of the transmitted ACT-bit is as follows:
The polarity of the issued SAI-bit depends on the received C/I-channel code: DI and TIM
leads to SAI = 0, any other C/I-code sets the SAI-bit to 1 indicating activity on the
S/T-interface.
4.4.3.4
This section describes the functions of all states defined in NT modes:
Alerting
The wake-up signal TN is transmitted for a period of T11 either in response to a received
wake-up signal TL or to start an activation procedure on the LT side.
NT States
Deactivation Confirmation
Idle code on the C/I Channel. The IEC-Q stays in the power-down mode
unless an activation procedure has been started from the LT side. The
U-interface may be activated but the S/T-interface has to remain
deactivated.
Deactivation Request
The IEC-Q has detected a deactivation request command from the LT side
for a complete deactivation or a S/T only deactivation. In an NT1, the
S-transceiver is requested to start the deactivation procedure on the
S/T-interface by sending INFO0.
Error Indication 1
The IEC-Q has entered a failure condition caused by loss of framing on the
U-interface or expiry of timer T1.
Interrupt (Stand-alone mode only)
A level change on input pin INT triggers the transmission of this C/I code for
four successive IOM
details.
Power Up
The IEC-Q provides IOM
a = 0/1 corresponds to ACT-bit set to binary "0/1"
®
-2 frames. Please refer to "Interrupt", page 197 for
®
-2 clocks.
168
Operational Description
Data Sheet 01.99
PEB 2091
PEF 2091