PXF4333 Datasheet, PDF (113/361 Pages) Infineon Technologies AG – ABM 3G ATM Buf fer Manager

ABM-3G
PXF 4333 V1.1
Operational Description
Given a particular tauS, the burst tolerance BT and the corresponding MBS produced by
the leaky bucket shaper is calculated as:
BT
=
--^t--^a----^u---^S----
Tstep
×
----------³---²-----------
SYSCLK
[ sec ]
(22)
and
MBS = 1 + -^t--^a---^u----^S-----^×-----⁶---⁴--
[ cells ]
(23)
TS – TP
The maximum BT has been derived from tauS_max and is shown in Table 4-6 for different
values of TstepC and SYSCLK.
Table 4-6 Maximum BT as a Function of TstepC and SYSCLK
TstepC
1/Tstep
0
1
2
3
4
5
6
7
BT [s]
SYSCLK = 51.84 [MHz] SYSCLK = 60 [MHz]
256
10.192
8.807
128
5.097
4.403
64
2.548
2.201
32
1.274
1.100
16
0.637
0.550
8
0.318
0.275
4
0.159
0.137
2
0.079
0.068
Refer to “AVT Context Table: VBR Shaping (Table Layout)” on Page 97 for a
detailed description and layout of the parameter fields.
Data Sheet
113
2001-12-17