Motorola PowerQUICC II MPC8280 Series Reference Manual page 1045

• End-to-end (identified by PTI = 5)—This flow is used for end-to-end VCC
operations communications. Cells inserted into this flow can be removed only by
VC endpoints.
• Segment (identified by PTI = 4)—This flow is used for communicating operations
information with the bound of one VCC link or multiple interconnected VCC links.
A concatenation of VCC links is called a VCC segment. Segment endpoints must
remove these cells to prevent confusion in adjacent segments.
31.6.4 Receiving OAM F4 or F5 Cells
OAM F4/F5 flow cells are received using the raw cell queue, described in Section 31.4.4,
"Receive Raw Cell Queue." An F4/F5 OAM cell which does not appear in the CAM or
address compression tables is considered a misinserted cell.
31.6.5 Transmitting OAM F4 or F5 Cells
OAM F4/F5 flow cells are sent using the usual AAL0 transmit flow. For OAM F4/F5 cell
transmission, program channel one in the TCT to operate in AAL0 mode. Enable the CR10
(CRC-10 insertion) mode as described in Section 31.10.2.3.3, "AAL0 Protocol-Specific
TCT." Prepare the OAM F4/F5 flow cell and insert it in an AAL0 TxBD. Finally, issue a
command to send the OAM cell. For multiple PHYs, use several AAL0
ATM TRANSMIT
channels—each PHY should have one transmit raw cell queue that is associated with its
scheduling table.
A series of OAM cells can be sent using one
of AAL0 TxBDs. If the channel's TCT[AVCF] (auto VC off) is set, the transmitter
automatically removes it from the APC (that is, it does not generate periodic transmit
requests for this channel after all AAL0 BDs are processed).
31.6.6 Performance Monitoring
A connection's performance is monitored by inspecting blocks of cells (delimited by
forward monitoring cells) sent between connection or segment endpoints. Each FMC
contains statistics about the immediately preceding block of cells. When an endpoint
receives an FMC, it adds the statistics generated locally across the same block to produce
a backward reporting cell (BRC), which is then returned to the opposite endpoint.
The MPC8280 can run up to 64 bidirectional block tests simultaneously. When a
bidirectional test is run, FMCs are generated for one direction and checked for the opposite.
MOTOROLA Chapter 31. ATM Controller and AAL0, AAL1, and AAL5
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command by creating a table
ATM TRANSMIT
OAM Support
31-31