TMXF28155 Supermapper
155/51 Mbits/s SONET/SDH x28/x21 DS1/E1
Data Sheet
June 2002
12 28-Channel Framer Registers (continued)
Table 434. FRM_ARLR2, Arbiter Link Register 2 (R/W) (continued)
Address*
Bit
Name
Function
Reset
Default
0x8LPF1 13:12
FRM_OPT[1:0]
Frame Options.
0
DS1 Mode:
00 = the frame aligner will not frame up until all mimics are
gone.
01 = time-out algorithm is enabled. A counter is started
when, for the first time, one of the 193-bit positions
contains a sequence long enough to declare frame
but is prevented from doing so by the presence of a
mimic. The provisionable counter sets a time limit for
mimics to go away. If there are still mimics, a
candidate bit position that has met the minimum
framing requirements is chosen and frame alignment
is made to that position. See FRM_TO[7:0]
(Table 317).
Others reserved.
CEPT Mode:
00 = no change.
01 = enables an extra NOTFAS frame check. This can
prevent frame alignment on PRBS patterns which
contain a pseudoframing pattern. The CEPT framing
sequence now becomes:
Find FAS (n).
Verify NOTFAS frame (n + 1).
Verify second FAS in frame (n + 2).
Verify second NOTFAS frame (n + 3).
Others reserved.
11
FRM_FBE_MODE
DDS FBE Mode.
0
0 = allows two FBEs to be detected in a frame in DDS
mode: one FBE for the frame bit (FT and FS) and one
FBE for the time slot 24 frame alignment signal.
1 = only 1 FBE is detected in a frame in DDS mode.
* See Table 429 on page 298 for values of L and P.
302
Agere Systems Inc.
ETC [ ETC ]
