S/UNI-IMA-4 Telecom Standard Product Data Sheet
Released
RDAT Validation Memory (MEM_SELECT=3)
Purpose: Contains configuration information for each Physical Link. Used by the RDAT to
validate incoming ICP cells in IMA mode, and to control the flow of data to the DCB’s. For TC
Links, the single bit tc_mode bit must be set. For IMA links, this record should be cleared
before link addition.
Usage: IMA Groups and TC Links.
Maintained by: Microprocessor (for TC mode only), RIPP.
Record Size: Two 32-bit words.
MEM_ADDR = (Physical Link Number X 2) + Word Offset
Table 25 RDAT Validation Record
Word Bits
Parameter
tc_mode
Description
0
31
tc_mode controls whether the link is in TC mode or part of an
IMA group
0
IMA link. Flow of cells is controlled by the IMA
protocol and the current IMA state
1
TC Enabled. Cells received for this link are stored in
a four-cell FIFO in the SDRAM and scheduled for immediate
transmission out the group FIFO.
0
30:29
link_state
Link Data State. Valid only in IMA mode. This field reports the
current state as set by the RIPP to determine how the RDAT
should handle incoming cells:
00
Disabled. Cells are read from the link FIFOs and
dropped.
01
IMA startup. All ICP cells are forwarded to the RIPP
via the ICP FIFO, but the IFSM is not started and the delay
compensation buffers remain idle for this link.
10
IMA Monitor. The IFSM is enabled. ICP cells are
forwarded to the RIPP (all during the IFSM HUNT state, just
cells at the expected ICP cell position during the PRESYNC
and SYNC states). No cells are written to valid buffer locations
in the DCB, but the write pointers are incremented.
11
IMA Enabled. Same as IMA Monitor, except that user
and filler cells are written to the DCB.
Reserved.
28:26
25:24
m
IMA frame length. The value is programmed by the RIPP to
allow the RDAT to perform the IFSM, and to validate the value
for M in the incoming ICP cells.
00
01
10
11
32 cells
64 cells
128 cells
256 cells.
Proprietary and Confidential to PMC-Sierra, Inc., and for its customers’ internal use.
Document No.: PMC-2020889, Issue 2
218
PMC [ PMC-SIERRA, INC ]
