PEF2091 Siemens Semiconductor Group, PEF2091 Datasheet - Page 116

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

Semiconductor Group
issued, the corresponding position in the SB channel will be set to "1", which is the
default value after the signal SL2 in the LT modes and SN3 in the NT modes are issued
on the U-interface (see state machines, pages 146, 160 and 173).
SB Transmission in NT Modes
Note 34: This section applies if one of the modes NT, NT-Auto Activation, TE and
The Single Bits will be set in the following manner:
• The Single bit ACT is controlled internally by the activation/deactivation state machine
• Two different ways are available to control the Single bit SAI:
• The Single bit FEBE is controlled internally by the CRC processor (see "Monitoring
• The Single bit CSO is set to "0".
• The Single Bits PS1 and PS2 are programmed directly by the pins PS1 and PS2
• The bit NTM is programmed via the M-bits of the MON-1 messages NTM and NORM
• All of other Single Bits, i.e. M46, M48 M51, M52 and M61 can be set by the user via
Table 21 gives an overview of SB control, and Table 22 gives a brief explanation of the
function of the SB in this mode.
Table 21
MON-2/U
Position
(see "State Machine in NT Modes", page 160)
1- Internally by the activation/deactivation state machine (see "State Machine in NT
Modes", page 160), which is the default setting after power up.
2- By the MON-2 command.
Control via MON-2 can be set by issuing the MON-8 command PACE. To change this
setting back to IEC-Q internal control (1), the MON-8 command PACA can be issued.
(See "MON-8 Codes", page 228, for details about codes and programming of these
commands).
Transmission Quality", page 176). In addition the MON-8 message SFB can be issued
to set the FEBE bit to "0" once in the next available superframe (test mode, see
"MON-8 Codes", page 228, for details MON-8 codes and programming).
respectively (see "Power Controller Pins", page 36 and page 45). any change in the
pin polarity will be indicated at the corresponding position and transmitted in the next
available superframe (see "Monitoring Primary and Secondary NT Power Supply",
page 194).
(see "MON-8 Codes", page 228).
MON-2 messages.
M41
M51
NT-PBX is used (see "Basic Operating Mode", page 50).
Single Bits Control in NT Modes (Upstream)
ACT
Bit
1
NT –> LT
State Machine (IEC-Q)
116
Control
MON-2
Operational Description
Data Sheet 01.99
PEB 2091
PEF 2091