LAN9312 datasheet(81/458 Pages) SMSC

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High Performance Two Port 10/100 Managed Ethernet Switch with 32-Bit Non-PCI CPU Interface

Datasheet

SMSC LAN9312

Revision 1.2 (04-08-08)

DATASHEET

6.5.7

Counters

A counter is maintained per port that contains the number of packets dropped due to buffer space limits

and ingress rate limit discarding (Red and random Yellow dropping). These counters are accessible

via the following registers:

Buffer Manager Port 0 Drop Count Register (BM_DRP_CNT_SRC_MII)

Buffer Manager Port 1 Drop Count Register (BM_DRP_CNT_SRC_1)

Buffer Manager Port 2 Drop Count Register (BM_DRP_CNT_SRC_2)

A counter is maintained per port that contains the number of packets dropped due solely to ingress

rate limit discarding (Red and random Yellow dropping). This count value can be subtracted from the

drop counter, as described above, to obtain the drop counts due solely to buffer space limits. The

ingress rate drop counters are accessible via the following registers:

Buffer Manager Port 0 Ingress Rate Drop Count Register (BM_RATE_DRP_CNT_SRC_MII)

Buffer Manager Port 1 Ingress Rate Drop Count Register (BM_RATE_DRP_CNT_SRC_1)

Buffer Manager Port 2 Ingress Rate Drop Count Register (BM_RATE_DRP_CNT_SRC_2)

6.6

Switch Fabric Interrupts

The switch fabric is capable of generating multiple maskable interrupts from the buffer manager, switch

engine, and MACs. These interrupts are detailed in Section 5.2.2, "Switch Fabric Interrupts," on

page 51.

LAN9312 Datasheet(PDF) 81 Page - SMSC Corporation