CN8236EBGB Mindspeed Technologies, CN8236EBGB Datasheet - Page 203

• Manufacturer Part Number: CN8236EBGB
• Description: ATM SAR 155Mbps 3.3V ABR/CBR/GFR/UBR/VBR 388-Pin BGA
• Manufacturer: Mindspeed Technologies

Specifications of CN8236EBGB

• Package: 388BGA
• Traffic Class: ABR|CBR|GFR|UBR|VBR
• Utopia Type: Level 1|Level 2
• Host Interface: PCI
• Maximum Data Rate: 155 Mbps
• Typical Operating Supply Voltage: 3.3 V
• Minimum Operating Supply Voltage: 3 V

CN8236
ATM ServiceSAR Plus with xBR Traffic Management
Figure 6-20. ER RATE_INDEX Candidate Selection
28236-DSH-001-B
ER
two, each of which are
RATE_INDEX in the VCC’s SCH_STATE entry. Then, the CN8236 uses this
RATE_INDEX to point to the corresponding appropriate Rate Decision Block
(RDB) and, as specified in TM 4.1, updates the VCC’s rate parameter with the
RDB’s I and L parameters.
coprocessor passes the CI, NI, and ER fields from the RM cell to the ABR Flow
Control Manager via the RSM/SEG Queue. The Flow Control Manager uses the
ABR Rate Decision table and the Exponent table, both programmable
components of an ER template, to calculate the two RATE_INDEX candidates,
each of which are
candidate. Then the CN8236 updates the VCC’s rate parameters with the newly
selected rate index. This rate index points to a Rate Decision Block whose I and L
parameters establish the new rate. The Cell Scheduler uses the updated rate to
schedule all future traffic until the next rate update.
Figure 6-20
Once both candidates are identified, the CN8236 selects the smaller of the
Figure 6-21
Mindspeed Technologies
CANDIDATE
INDEX
illustrates the ER RATE_INDEX candidate selection.
provides a block diagram of this process. The reassembly
ER
MCR. The min() function is applied to select a winning
MCR. The winning candidate then replaces the current
CONNECTION STATE (RATE_INDEX)
™
6.3 ABR Flow Control Manager
6.0 Traffic Management
8236_052
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