Released
Datasheet
PM73487 QRT
PMC-Sierra, Inc.
PMC-980618
Issue 3
622 Mbps ATM Traffic Management Device
Table 40. Channel Control Block Summary (Continued)
Read or
Byte
Offset Offset
Long
Name
Description
Write
2Ch
30h
34h
38h
3Ch
Bh
Ch
Dh
Eh
Fh
TX_NEW_VPI_RESEQ_PTR
TX_CH_STATE
R/W
VPI to which you want to translate and the pointer to the resequencing
buffer.
R/W (init
only)
Current channel state.
TX_CH_RESEQ_ST
R/W (init
only)
State of the resequencing algorithm.
Count of transmit cells sent.
Count of transmit cells dropped.
TX_CH_CELLS_SENT
TX_CH_CELLS_DRPD
R/W (init
only)
R/W (init
only)
9.3.1.1 RX_CH_CONFIG
Offset: 0h (0h byte)
Type: Read/Write
Format: Refer to the following table.
Field (Bits)
Description
RX_CH_EXP_MAX_QD
(31:28)
Exponent of the maximum per-SC queue depth. Initialize to the proper setting. Limits
RX_CH_CUR_QD (refer to “RX_CH_CUR_QD” on page 187) to:
RX_CH_CUR_QD ≤ 1 + 2RX_CH_EXP_MAX_QD
A value of 0h causes all cells for this channel to be dropped. A value of Fh limits this
channel to 31744 cells.
RX_CH_EXP_CONG_QD
(27:24)
Exponent of the congested channel queue depth. Initialize to the proper setting. The
congestion state is entered when the threshold is exceeded, and the congestion state is
exited when the queue length drops below 50 percent of this threshold. Enables conges-
tion management when:
RX_CH_CUR_QD > 1 + 2 RX_CH_EXP_CONG_QD
A value of 0h causes this channel to be in congestion at all times. A value of 1h may not
be used. A value of Fh causes this channel to enter congestion at a depth of 31744 cells.
RX_CH_ENTRY_PRESENT
(23)
Initialize to 0, set other variables, then initialize to the proper setting.
1
0
Indicates the entry is present and valid.
Indicates the entry is disabled. Drop any cells received at this index.
Not Used
(22)
Initialize to 0 to maintain future compatibility
Indicates the SC.
RX_CH_SERVICE_CLASS
(21:16)
RX_CH_EN_CLP_DROP
(15)
Initialize to the proper setting.
1
Enables CLP dropping when either the channel, the SC, or the device is in
the congested state.
0
Disables CLP dropping above the congestion threshold.
Not used
(14)
Write with a 0 to maintain software compatibility with future versions.
184
PMC [ PMC-SIERRA, INC ]
