
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
314
RDAT TC Link Context Memory (MEM_SELECT=0xA)
Purpose: Contains state information for each TC Link. VPHY_ID is the only field
that must be configured.
Usage: TC Links only.
Maintained by: RDAT, microprocessor.
Record Size: One 32-bit word.
MEM_ADDR = TC Tag
Table 29
RDAT TC Link Context Record
Bits
Parameter
Description
31:16
vphy_id
Virtual PHY ID.
For UTOPIA L2 Multi-Address mode, this identifies
which channel in the RXAPS FIFO cells received for
this group will be written to. The least significant 5 bits
determine the destination channel of the RXAPS FIFO
for this IMA group, and the upper 11-bits are unused.
For Any-PHY and UTOPIA L2 Single-Address modes,
this identifies the address which will be prepended to all
cells as they are written to the single channel RXAPS
FIFO. For single channel UTOPIA mode and Any-PHY
mode, the least significant 7 bits must uniquely identify
a channel (legal values of 0-83) and the upper 9 bits are
user selectable.
15:0
read_ptr
Current read pointer for the delay compensation buffers
associated with this TC connection.
Receive ATM Congestion Count Register (MEM_SELECT=0xD)
Purpose: Contains a global count of the number of cells dropped due to Receive
Cell Interface congestion. RDAT increments this counter and sets one of the
Receive ATM Congestion Status bits each time it drops a cell.