PEF2091 Siemens Semiconductor Group, PEF2091 Datasheet - Page 117

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

Table 21
Table 22
Bit
ACT
CSO
SAI
FEBE
Semiconductor Group
M61
M42
M52
M62
M43
M44
M45
M46
M47
M48
Function
The ACT-bit is part of the start-up sequence and is used to indicate layer 2
to be ready for communication. In this case it is set to (1)
(Cold Start Only)
The CSO-bit signals the network side whether the NT is only capable of
being started via cold start
(S Activity Indicator)
The SAI-bit informs the LT side about the state of the S-interface. With the
S-interface deactivated (i.e. C/I-commands TIM or DI received), the SAI-bit
is set to (0). Additionally the bit SAI is used (with SAI = (1)) in a terminal
initiated activation (if the U-interface was active before) to request complete
NT activation
(Far-End Block Error)
The FEBE-bit is used to inform the opposite U-interface station that the
transmitted data could not be received free of errors. The device sets the
FEBE-bit to (0) if errors were observed. Each time a FEBE = (0) is detected,
the count of the internal far-end block error counter will be incremented.
Additionally it is possible to control the FEBE-bit with the MON-8-message
"SFB"
(Activation bit)
Single Bits Control in NT Modes (Upstream)
Function of the Predefined SB in NT Modes
FEBE
NTM
CSO
PS1
PS2
SAI
1
1
1
1
CRC processor (IEC-Q) and MON-8
State Machine (IEC-Q) / MON-2
117
"0" (IEC-Q)
Pin PS1
Pin PS2
MON-2
MON-2
MON-1
MON-2
MON-2
Operational Description
Data Sheet 01.99
PEB 2091
PEF 2091