TMXF28155/51 Super Mapper
155/51 Mbits/s SONET/SDH x28/x21 DS1/E1
Preliminary Data Sheet
May 2001
578
Agere Systems Inc.
24 Test-Pattern Generation/Detection Functional Description
(continued)
The transmitted Sa bits (designated as spares in G.704) are a continuous repeat of the contents of the
TPG_E1SAx[4:8] registers (
Table 505
and
Table 506
). These bits are synchronized to the CRC-4 frame. Referring
to Table 5B in G.704, the E1SA1[4:8] bits are the SA bits in SMF 1 and 9, the E1SA2[4:8] bits are the Sa bits in
SMF 3 and 11, etc.
24.5.7 DS2 TPG Framing
The DS2 generator provides an unframed DS2 rate test sequence.
24.5.8 DS3 TPG Framing
For DS3 test signals, the TPG provides a raw PN sequence on TPG_DATA[5] using the enabled clock.
24.5.9 Line Encoding/Decoding
For DS1 and E1 test signals, the TPG may be provisioned to transmit and receive AMI coded signals
TPG_TPM_CODEx (
Table 507
and
Table 508
). The signals can be uncoded, B8ZS coded, HDB3 coded, or AMI
coded. If coding is selected, it is active for both transmit and receive paths. For coded signals, the DATA inputs/out-
puts become the positive rails and the sync inputs/outputs become the negative rails.
24.5.10 TPG Test-Pattern Sequences
The test-pattern bit sequence generated on the nonidle TPG_DATAx lines is determined by the TPG_SEQm[2:0]
(
Table 507
,
508
,
509
, and
510
) register values, where m is the rate index (0 = DS1, 2 = E1, 4 = DS2,
and 5 = DS3). One of seven sequences presently may be selected for transmission within the framed or unframed
test pattern on the corresponding even TPG_DATAx lines (the odd lines are connected to idle generators). Each
datastream also has an associated clock TPG_CLKx and frame-sync signal TPG_FSx (x even, except DS2).
TPG_SEQm[2:0] values are described in the following table:
The polarity of the output data stream may also be provisioned to normal TPG_TPINVx = 0 (
Table 507
,
508
,
509
,
and
510
) or inverted TPG_TPINVx = 1.
Table 625. TPG Test-Pattern Sequences
TPG_SEQm
000
Test Pattern
PRBS15.
2
15
–
1 PN sequence specified in O.150. This sequence is generated by a 15-stage
shift register whose 14th and 15th stages are added and fed back to the first stage. The output of
the last stage is inverted (which yields a sequence with up to 15 consecutive zeros) to produce
the transmitted sequence.
PRBS20.
2
20
–
1 PN sequence. This sequence is generated by a 20-stage shift register whose
17th and 20th stages are added and fed back to the first stage. The transmitted test sequence is
normally the noninverted output of the last (20th) stage.
QRSS.
2
20
–
1 PN sequence with zero-suppression as specified in O.150. This sequence is gen-
erated by a 20-stage shift register whose 17th and 20th stages are added and fed back to the first
stage. The transmitted test sequence is normally the non-inverted output of the last (20th) stage,
but the test sequence is forced high if the outputs of stages 6 through 19 are low.
PRBS23.
2
23
–
1 PN sequence.
ALT_01.
Alternating sequence of ones and zeros.
ALL_ONES.
All-ones sequence.
001
010
011
100
101
Note:
If unframed, an AIS signal is generated.
Reserved.
User-Defined.
Continuously repeating 16-bit pattern from TPG_USER[15:0] (
Table 511
).
110
111