Motorola PowerQUICC II MPC8280 Series Reference Manual page 1154

Receive and Transmit Connection Tables (RCT, TCT)
Table 32-7 describes general TCT fields.
Offset Bits Name
0x00 0–1 —
2 GBL
3–4 BO
5 —
6 DTB
7 BIB
8-9 —
10-11 ATT
12 AVCF
13 VCON
14–15 INTQ
32-34
Freescale Semiconductor, Inc.
Table 32-7. TCT Field Descriptions
Reserved, should be cleared during initialization.
Global. Asserting GBL enables snooping of data buffers, BDs, interrupt queues and free
buffer pool.
Byte ordering. This field is used for data buffers.
00 Reserved.
01 Power PC little endian.
1x Big endian.
Reserved, should be cleared during initialization.
Data buffer and CES transmit cell scratchpad bus placement
0 Reside on the 60x bus.
1 Reside on the local bus.
Note: TCT[DTB] programming must be consistent across all CES transmit channels
because they share the same TCELL_TMP_BASE_EXT parameter.
BD and interrupt queue bus
0 Reside on the 60xbus.
1 Reside on the local bus.
Note: When using AAL5, AAL1 or AAL1 CES in UDC mode, BDs and data should be
placed on the same bus (TCT[DTB]=TCT[BIB]).
Reserved, should be cleared during initialization.
ATM traffic type
00 Peak cell-rate pacing. The host must initialize PCR and the PCR fraction. Other
traffic parameters are not used.
01 Peak and sustain cell rate pacing (VBR traffic). The APC performs a
continuous-state leaky bucket algorithm (GCRA) to pace the channel-sustain cell
rate. The host must initialize PCR, PCR fraction, SCR, SCR fraction, and BT (burst
tolerance).
10 Peak and minimum cell rate pacing (UBR+ traffic). The host must initialize PCR, PCR
fraction, MCR, MCR fraction, and MDA.
11 Reserved.
Auto VC off. Determines APC behavior when the last buffer associated with this VC has
been sent and no more buffers are in the VC's TxBD table,
0 The APC does not remove this VC from the schedule table and continues to schedule
it to transmit.
1 The APC removes this VC from the schedule table. To continue transmission after the
host adds buffers for transmission, a new
can be issued only after the CP clears the VCON bit. (Bit 13)
Virtual channel is on
Should be set by the host before it issues an
sets TCT[STPS] (stop transmit), the CP deactivates this channel and clears VCON
when the channel is next encountered in the APC scheduling table. The host can issue
another command only after the CP clears VCON.
ATM TRANSMIT
Points to one of four interrupt queues available.
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Description
command is needed, which
ATM TRANSMIT
command. When the host
ATM TRANSMIT
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