
Preliminary Data Sheet, Rev. 1
October2000
TMXF28155 Super Mapper
155/51 Mbits/s SONET/SDH x28/x21 DS1/E1
213
Lucent Technologies Inc.
SPE Mapper Functional Description
(continued)
SPE Mapper Receive Direction Requirements
(continued)
Table 114. Signal Degrade Parameters
Note:
The thresholds written by the control system is one less than the desired number, except for the
SPE_SDLSET[3:0]/SDLCLEAR[3:0] parameter.
Signal Fail BER Algorithm
A signal fail state is reported by bit SPE_SFB3 (Table 124) and change of state in bit SPE_SFB3D (Table 122) with
the interrupt mask bit SPE_SFB3M (Table 123). This bit error rate algorithm operates on B3 errors.
Declaring the signal fail state requires the definition of two measurement windows. A monitoring block consisting of
a number of frames, Ns (SPE_SFNSSET[18:0] (Table 135)), and a measurement interval consisting of a number of
monitoring blocks, B (SPE_SFBSET[15:0] (Table 135)). A block is determined bad when the number of bit errors
equals or exceeds a threshold, L (SPE_SFLSET[3:0] (Table 135)). Signal fail is declared when the number of bad
monitoring blocks equals or exceeds the threshold, M (SPE_SFMSET[7:0] (Table 135)), for the measurement
interval.
Name
Function
SPE_SDNSSET[18:0] (Table 134)
SPE_SDLSET[3:0] (Table 134)
Signal Degrade Ns Set.
Number of frames in a monitoring block for SD.
Signal Degrade L Set.
Error threshold for determining if a monitoring
block is bad.
Signal Degrade M Set.
Threshold of the number of bad monitoring
blocks in an observation interval. If the number of bad blocks is below
this threshold, then SD is cleared.
Signal Degrade B Set.
Number of monitoring blocks in a measurement
interval.
SPE_SDMSET[7:0] (Table 134)
SPE_SDBSET[15:0] (Table 134)
SPE_SDNSCLEAR[18:0] (Table 134)
Signal Degrade Ns Clear.
Number of frames in a monitoring block for
SD.
SPE_SDLCLEAR[3:0] (Table 134)
Signal Degrade L Clear.
Error threshold for determining if a monitoring
block is bad.
SPE_SDMCLEAR[7:0] (Table 134)
Signal Degrade M Clear.
Threshold of the number of bad monitoring
blocks in an observation interval. If the number of bad blocks is below
this threshold, then SD is cleared.
SPE_SDBCLEAR[15:0] (Table 134)
Signal Degrade B Clear.
Number of monitoring blocks in a measure-
ment interval.
SPE_SDSET (Table 121)
Signal Degrade Set.
Allows the signal degrade algorithm to be forced
into the failed state (active 0 to 1).
SPE_SDCLEAR (Table 121)
Signal Degrade Clear.
Allows the signal degrade algorithm to be forced
into the normal state (active 0 to 1).
SPE_SDB3 (Table 124)
Signal Degrade BER Algorithm State Bit.
SPE_SDB3D (Table 122)
Signal Degrade BER Algorithm Delta Bit.
SPE_SDB3M (Table 123)
Signal Degrade BER Algorithm Mask Bit.