PM7345S Datasheet, PDF (247/306 Pages) PMC-Sierra, Inc – SATURN USER-NETWORK INTERFACE FOR ATM PLESIOCHRONOUS DIGITAL HIERARCHY DATACOM

DATA SHEET
PMC-931011
ISSUE 6
PM7345 S/UNI-PDH
SATURN USER-NETWORK INTERFACE
RDLSIG. When not configured for Tandem Connection
Maintenance, all 8 bits of the Network Operator byte are extracted
and presented on ROH, RDLSIG, or to RFDL. When configured for
Tandem Connection, the first four bits of the byte are accumulated
by S/UNI-PDH and the last four bits of the byte are output on ROH,
RDLSIG, or terminated by RFDL.
• GC : General Purpose Communication Channel
Transmit: The S/UNI-PDH inserts the GC byte from the TOH overhead
stream or, optionally, from the XFDL or the TDLSIG input.
Receive: The S/UNI-PDH extracts the GC byte and outputs it on ROH or,
optionally, terminates it in RFDL or outputs it on RDLSIG.
12.5 S/UNI-PDH Cell Data Structure
ATM cells are passed to/from the S/UNI-PDH transmit and receive FIFOs using a 53
word data structure. The data structure is shown in figure 10.
Figure 10 - Cell Data Structure
Bit 7
Word 1
Word 2
Word 3
Word 4
Word 5
Word 6
Bit 0
H1
H2
H3
H4
H5
PAYLOAD1
Word 53
PAYLOAD48
Fifty-three 8-bit words are contained in this data structure. Bit 7 of each word is the
most significant bit and corresponds to the first bit transmitted or received. The start
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE 233