Motorola PowerQUICC II MPC8280 Series Reference Manual page 1273

34.5.4.3.1 As Initiator (TX)
Most of the actions required when a system initiates the establishment of a group with X
links involves the exchange of ICP cells between the Near End (Initiator) and the Far End
(Responder). In any case, both ends must start with a group of X potential links configured
to "filler mode". One and only one of the links in the group must be designated as TRL.
• Set ILTCNTL[TXSC] to 0 (zero)—link is in filler mode.
• Set IGTCNTL[TXSC] to 0 (zero)—group is in filler mode.
The actions at both ends mirror each other. That is, the Near End will initiate the
establishment of a group with X links by sending ICP cells to the FE and vise versa. The
normal ICP state changes, driven by the state machine software, are (on a per-link basis):
1. Not In Group
2. Unusable
3. Usable
4. Active
Refer to section "Transmit ICP Cell Signalling" for details on how to modify and transmit
an updated ICP cell.
It is the responsibility of the GSM/LSM (Group/Link State Machine software) to initialize
the IMA ID (i.e. group ID) in the ICP cell template and link ID in the corresponding TX
IMA Link Transmit Table Entry (ILTTE):
• Set ILTTE[ILID] = corresponding Link ID.
• Set IMA ID accordingly in the ICP Cell Template.
As an initiator, the NE ("end" is relative) must have established a group with X links
provisioned.
GSM/
LSM
MOTOROLA
Freescale Semiconductor, Inc.
Tx ICP Template
TX
Near-end
MPC8280
RX
ICP buffer
Figure 34-33. Near-End versus Far-End
Chapter 34. Inverse Multiplexing for ATM (IMA)
For More Information On This Product,
Go to: www.freescale.com
IMA Software Interface and Requirements
Tx ICP Template
TX
Far-end
MPC8280
RX
ICP buffer
GSM/
LSM
34-63