Motorola PowerQUICC II MPC8280 Series Reference Manual page 1185

0
Channel identifier (CID)
33.3.5.4 SSSAR Tx Queue Descriptor
A SSSAR TxBD table and its associated buffers are collectively called an SSSAR TX
Queue. Each SSSAR TX Queue is managed by an SSSAR TxQD, as shown in
Figure 33-11. The TxQD contains the base address of the BD table, the offset of the next
BD to be serviced, the data buffer pointer, and other queue-specific parameters. The
NextQueue pointer is used to create a linked list of TxQDs, as described in Section 33.3.2,
"Transmit Priority Mechanism." The SSSAR TxQD is located in the dual-port RAM in a
32-byte aligned address.
0
Offset + 0x00
Offset + 0x02
Offset + 0x04
Offset + 0x06
Offset + 0x08
Offset + 0x0A
Offset + 0x0C
Offset + 0x0E
Offset + 0x10
Offset + 0x12
Offset + 0x14
Offset + 0x16
Offset + 0x18
Offset + 0x1a
Offset + 0x1C
Offset + 0x1E
MOTOROLA
Freescale Semiconductor, Inc.
7 8
Length indicator (LI)
Figure 33-10. CPS Packet Header Format
—
Seg_Len
TxBD Table Offset Out
Figure 33-11. SSSAR Tx Queue Descriptor
Chapter 33. ATM AAL2
For More Information On This Product,
Go to: www.freescale.com
13 14 18
User-to-user ID (UUI)
7 8 9 10
BNM UUI INF
TxBD Table Base
—
NextQueue
—
AAL2 Transmitter
19
Header error check (HEC)
11 12 13 14
CPS TBM SSSAR —
—
33-17
23
15