LAN9353 Datasheet, PDF (216/523 Pages) Microchip Technology – Interfaces at up to 200Mbps via Turbo MII

LAN9353
TABLE 10-2: TYPICAL INGRESS RATE SETTINGS
CIR Setting
Time Per Byte
Bandwidth
79
1600 ns
5 Mbps
160
3220 ns
2.5 Mbps
402
8060 ns
1 Mbps
804
16100 ns
500 kbps
1610
32220 ns
250 kbps
4028
80580 ns
100 kbps
8056
161140 ns
50 kbps
After each packet is received, the bucket is decremented. If the Committed Burst bucket has sufficient tokens, it is deb-
ited and the packet is colored Green. If the Committed Burst bucket lacks sufficient tokens for the packet, the Excess
Burst bucket is checked. If the Excess Burst bucket has sufficient tokens, it is debited, the packet is colored Yellow and
is subjected to random discard. If the Excess Burst bucket lacks sufficient tokens for the packet, the packet is colored
Red and is discarded.
Note:
All of the token buckets are initialized to the default value of 1536. If lower values are programmed into the
CBS and EBS parameters, the token buckets will need to be normally depleted below these values before
the values have any effect on limiting the maximum value of the token buckets.
Refer to Section 10.7.3.26, on page 312 through Section 10.7.3.30, on page 315 for detailed register descriptions.
10.3.6.1 Ingress Flow Calculation
Based on the flow monitoring mode, an ingress flow definition can include the ingress priority. This is calculated similarly
to the transmit queue with the exception that the Traffic Class table is not used. As shown in Figure 10-2, the priority
can be based on:
• The static value for the destination address in the ALR table
• The precedence bits in the IPv4 TOS octet
• The DIFFSERV mapping table indexed by the IPv4 TOS octet or the IPv6 Traffic Class octet
• The VLAN tag priority field using the per port Priority Regeneration table
• The port default with separate values for packets with or without a broadcast destination address.
DS00001925A-page 216
 2015 Microchip Technology Inc.