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PRELIMINARY
INVERSE MULTIPLEXING OVER ATM
PM7340 S/UNI-IMA-8
DATA SHEET
PMC-2001723
ISSUE 3
INVERSE MULTIPLEXING OVER ATM
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
279
12.5.11
Deleting a Link from a Group
A link can be deleted from a group by using the delete Link command. On the
transmit side, the link will stop accepting ATM cells immediately and will transmit
filler cells only. The links will be removed from the TX round-robin on the next
frame boundary. On the receive side, the deleted link/links will transition to the
Deleted state to ensure that all transmitted data is received into the DCB buffer.
Once the FE TX state is detected as not active or the RX_LINK_DELETED
timeout occurs, the RX links stop writing data to the DCB buffers. The DCB
buffers allowed to underrun (preserving any previously stored data) prior to being
disabled and removed from the receive round-robin. The RX_ENABLE bits and
TX_ENABLE bits in the RIPP Link context records should be monitored to
determine when the links can be reassigned to a different group.
12.5.12
Test Pattern Procedures
The test pattern procedure consists of 2 parts, issuing the test pattern and
checking the test pattern.
To issue a test pattern, the update_tst_ptn command is used. This starts the
transmission of the new test pattern. The S/UNI-IMA-8 will always loopback the
test pattern indicated in the ICP cell.
Since each link may experience different round trip delays, the checking of the
test pattern is split between the user and the S/UNI-IMA-8. The S/UNI-IMA-8 will
compare test pattern received in the ICP cell with the test pattern that was sent
on every received ICP cell. The S/UNI-IMA-8 stores the success or failure of this
operation in the word 9 of the RIPP Group configuration register. The user is
responsible for checking the results after a sufficient time has passed for a round
trip delay on all links.
NOTE
: If no ICP cells are received for a particular LID, the
RX_TEST_PTN_Match field is never updated.
12.5.13
IMA Events
All of IMA events are reported via a group-based structure. IMA events include
link defects and link and group state machine changes. Any enabled IMA event
will cause a RIPP_INTR. All IMA events may be enabled for reporting at the
Goup/link level as well as a globally. Both the individual link/group enable as well
as the global enable must be set to have an IMA event cause an RIPP_INTR.