
PRELIMINARY
INVERSE MULTIPLEXING OVER ATM
PM7341 S/UNI-IMA-84
DATASHEET
PMC-2000223
ISSUE 4
INVERSE MULTIPLEXING OVER ATM
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
336
Transmit Physical Link Context Table (MEM_SELECT=2)
Purpose: Contains state information and statistics for each TC Link or IMA Link.
Each record is addressed by either the TC tag from the IDCC or the physical link
tag from the Transmit-LID-to-Physical-Link mapping Table.
Usage: IMA Groups and TC Links.
Maintained by: TIMA and microprocessor.
Record Size: Two 32-bit words.
MEM_ADDR = (Physical Link Tag or TC Tag X 2) + Word Offset
Table 34
TIMA Physical Link Context Record
Word Bits
Parameter
Description
31:24 unused
unused
23:16 ICP offset or TC
mode VPHY
address
IMA mode
: this field is indexed by the Physical
Link tag and is used to determine the cell count
within a frame at which an ICP is to be inserted
for the link. The width of the field used by the
TIMA is dependent on the value of M used for the
particular group and is shown in the following:
M=256 ICP offset determined by bits [23:16]
M=128 ICP offset determined by bits [23:17]
M=64 ICP offset determined by bits [23:18]
M=32 ICP offset determined by bits [23:19]
The mapping of the ICP offset is set such that the
offset should not have to be changed if M is
changed. Values 0 to 255 are valid.
TC mode
: this field is indexed by the TC tag
delivered by the IDCC and is used to determine
the VPHY ATM source FIFO associated with the
TC connection. Only values 0 to 83 are valid.
0
15:9
Reserved