PXF4336 Datasheet, PDF (126/425 Pages) Infineon Technologies AG – ABM Premium ATM Buf fer Manager

ABM-P
PXF 4336 V1.1
Functional Description
3.6.9.4 AVT Context RAM Section for VBR Shaping Support
In VBR shaping mode, one connection entry requires one AVT Context RAM section with
a total of four double words. Since the AVT table is accessed from the external micro
controller via a 16-bit transfer register, the VBR connection context appears as a 16-bit
organized table with 8 entries as shown in Table 3-57:
Table 3-57 AVT Context Table: VBR Shaping (Table Layout)
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
0 Config(6:0)
TET(23:16)
1 TET(15:0)
2a ST1(12:0)
ST0(12:10)
3a ST0(9:0)
STf(5:0)
2b unused
VDT(18:16)
3b VDT(15:0)
4 unused TeV Temit(12:0)
5 tauS(15:0)
6 TS(15:0)
7 TP(15:0)
Note: Entry 2/3 is used for 2 purposes:
a) Internal Relog–Relog/Reschedule: two possible ST values for low and high
priority cells
b) Relog/Reschedule–Emit: VDT of next cell
Table 3-58 AVT Context Table: VBR Shaping Parameter Description
Parameter
Initial
Value
Comment
Config(6:0) configure See Section 3.6.9.5 for mapping
tauS(15:0)
configure Delay tolerance parameter tau for SCR
extension (15:10) and integer (9:0) part
TP(15:0)
configure Rate parameter for peak rate limiter
integer (15:6) and fractional (5:0) part
TS(15:0)
configure Rate parameter for SCR-Leaky Bucket
integer (15:6) and fractional (5:0) part
TET(23:0) don’t care Theoretical Emit Time for SCR
VDT(18:0)
don’t care Virtual departure time of cell
extension (18:16), integer (15:6) and fractional (5:0) part
Data Sheet
126
2001-12-17