Motorola PowerQUICC II MPC8280 Series Reference Manual page 1275

10. Program expected LID: ILID = x
11. Program the expected ICP offset: LICPOS = x
12. Initialize the DCB pointers accordingly: DCBEP, DCBSP, DCBFP. Note, it is
recommended that the DCB be initialized to zero.
13. Configure link to "Loss of IMA Frame" state: ILRSTATE[FSES] = 2.
14. Start the IMA Frame Synchronization Mechanism (IFSM) by assigning this link to
the group: ILRCNTL[GA] = 1.
15. Software must now wait for the IFSW (IMA Frame Synchronization Working)
event/exception.
16. Now that we have a "frame" synchronized link, we can proceed to allow the link to
be "delay" synchronized. Indicate that this is a new link (GDS/reconstruction
function) by inverting the current "add-new" bit value:
ILRCNTL[ADD_NEW] = x.
17. Formulate new group order table with the new link included (see
Section 34.4.4.2.4, "Receive Group Order Tables").
18. Use the new group order table by inverting the current GOTP value:
IGRCNTL[GOTP] = x.
19. The "Stall Threshold" needs to be recalculated. This parameter defines the
acceptable tolerance to an emptied DCB condition (stalled link, see LS exception).
The recommended new value is: STALL_THR = 2 x RNUMLINKS x (3 +
RX_FIFO). See Section 34.4.4.2, "IMA Group Receive Table Entry":
IGRTE[STALL_THR] = x.
20. Start the delay compensation process for this link (in IMA Root Table) by setting
the corresponding bit in REF_LINK. See Table 34-3.
21. Software must now wait for the link delay synchronization process to complete. A
LDS (Link Delay Synchronized) exception will be generated by the MPC8280 as
soon as this happens.
22. It is now safe for the link to receive data, set link to "active" mode:
ILRCNTL[RXSC] = 1.
34.5.4.4.2 TX Parameters
1. Reset all TX parameters in the new link table entry to zero.
2. Assign corresponding group number for the new link: ILTCNTL[IGNUM] = x.
3. Enable desired interrupts: ITINTMSK = x.
4. Software formats content of ICP template accordingly (see section "Transmit ICP
Cell Signalling").
5. Program the Link's ID (LID) in the IMA Link Transmit Table Entry (ILTTE):
ILID = x.
MOTOROLA
Freescale Semiconductor, Inc.
Chapter 34. Inverse Multiplexing for ATM (IMA)
For More Information On This Product,
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IMA Software Interface and Requirements
34-65