PM5364 pmc-sierra, PM5364 Datasheet - Page 123

• Manufacturer Part Number: PM5364
• Description: Tupp 2488 Assp Telecom Standard
• Manufacturer: pmc-sierra

Proprietary and Confidential to PMC-Sierra, Inc., and for its customers’ internal use.
Document No.: PMC-2011334, Issue 7
Extended PSL
When extended PSL mode is configured (EXTDPSL is set to logic 1, only allowed when
PSLMODE is set to logic 1) in the RTOP336, the extended PSL is located in bit 1 of K4 byte
over 32 multi-frames. Figure 25 shows the extended PSL bit sequence. The multi-frame
alignment signal (MFAS) consists of “0111 1111 110”. The extended signal label (extPSL) is
contained in bits 12 to 19. Bit 20 is ignored in the MFAS alignment, and the remaining 12 bits
are reserved for future standardization and normal set to zero.
Figure 25 VC-1/2 Extended Signal Label (Extracted from ITU-T G.707)
The MFAS is detected by a multi-frame alignment state machine which is within the PSL
processor block. The MFAS state machine only search for the MFAS pattern in Out Of Multi-
Frame (OOM) state. Once the pattern is found, the MFAS state machine changes to In Multi-
Frame state (IM), and will continuously checked the presumed multi-frame state position for the
alignment. Only the first 11 bits of the 32 bit sequence is checked against the MFAS pattern for
frame alignment, the remaining bits will be ignored. The Frame alignment is lost (entering
OOM state) when two consecutive MFAS mismatch the MFAS alignment pattern “0111 1111
110”. The Frame alignment is deemed to have been recovered (entering the IM sate) when one
correct MFAS is found. When the MFAS is in OOM state and the tributary is configure to
extended PSL mode, the PSLM is set to high. Figure 26 shows the state diagram for the
multiframe alignment state machine.
Bit number:
1
MFAS
D
R
2
3
Multiframe alignment bits
Reserved bit
Don’t care
4
MFAS
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19
Extended Signal Label
TUPP™ 2488 ASSP Telecom Standard Product Data Sheet
20 21 22 23 24 25 26 27 28 29 30 31 32
D
R R R R R R R R R R R R
Released
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