S/UNI®-JET Data Sheet
Released
Table 37 E3 PLCP Trailer Length
C1(Hex)
Trailer Length
17 octets
18 octets
19 octets
20 octets
3B
4F
75
9D
A7
21 octets
13.4 DS3 Frame Format
The S/UNI-JET supports both M23 and C-bit parity DS3 framing formats. This format can be
extended to support direct byte mapping or PLCP mapping of ATM cells. An overview of the DS3
frame format is shown in Figure 12.
Figure 12 DS3 Frame Structure
680 bits (8 blocks of 84+1 bits)
M-subframe
X
F
F
F
F
F
F
F
C
C
C
C
C
C
C
F
F
F
F
F
F
F
C
C
C
C
C
C
C
F
F
F
F
F
F
F
C
C
C
C
C
C
C
F
F
F
F
F
F
F
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
Payload
1
1
2
1
2
1
2
3
1
1
1
1
1
1
1
1
1
1
1
1
1
1
2
2
2
2
2
2
2
2
2
2
2
2
2
2
3
3
3
3
3
3
3
3
3
3
3
3
3
3
4
4
4
4
4
4
4
X
2
3
P
P
4
5
6
7
M
M
M
84 bits
The DS3 receiver decodes a B3ZS-encoded signal and provides indications of LCVs. The B3ZS
decoding algorithm and the LCV definition are software selectable.
While in-frame, the DS3 receiver continuously checks for LCV, M-bit or F-bit framing bit errors,
and P-bit parity errors. When C-bit parity mode is selected, both C-bit parity errors and FEBEs
are accumulated.
When the C-bit parity framing format is detected, both the FEAC channel and the PMDL are
extracted. HDLC messages in the PMDL are received by an internal data link receiver.
The DS3 transmitter allows for the insertion of the overhead bits into a DS3 bit stream and
produces a B3ZS-encoded signal. Status signals such as FERF, AIS, and idle signal can be
inserted when the transmission of these signals is enabled
Proprietary and Confidential to PMC-Sierra, Inc., and for its Customers’ Internal Use
Document ID: PMC-1990267, Issue 3
267
PMC [ PMC-SIERRA, INC ]
