SMSC LAN9312 - Manual (Page 421)

High Performance Two Port 10/100 Managed Ethernet Switch with 32-Bit Non-PCI CPU Interface
Datasheet
SMSC LAN9312 421 Revision 1.4 (08-19-08)
DATASHEET
14.5.4.11 Buffer Manager Random Discard Table Write Data Register (BM_RNDM_DSCRD_TBL_WDATA)
This register is used to write the Random Discard Weight table.
Note: The Random Discard Weight table is not initialized upon reset or power-up. If a random discard
is enabled, the full table should be initialized by the host.
Register #: 1C0Ah Size: 32 bits
BITS DESCRIPTION TYPE DEFAULT
31:10 RESERVED RO -
9:0 Drop Probability
These bits specify the discard probability of a packet that has been colored
Yellow by the ingress metering. The probability is given in 1/1024’s. For
example, a setting of 1 is one in 1024, or approximately 0.1%. A setting of
all ones (1023) is 1023 in 1024, or approximately 99.9%.
There are a total of 16 probability entries. Each entry corresponds to a range
of the number of buffers used by the ingress port, as specified in
Section
14.5.4.10, "Buffer Manager Random Discard Table Command Register
(BM_RNDM_DSCRD_TBL_CMD)"
.
R/W 000h