SMSC LAN9420i Manual De Usuario

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Single-Chip Ethernet Controller with HP Auto-MDIX Support and PCI Interface
Datasheet
Revision 1.22 (09-25-08)
106
SMSC LAN9420/LAN9420i
DATASHEET
4.3.3
Receive Poll Demand Register (RX_POLL_DEMAND)
This register enables the RX DMAC to check for new descriptors.
Offset:
0008h
Size:
32 bits
BITS
DESCRIPTION
TYPE
DEFAULT
31:0
Receive Poll Demand (RPD)
When written with any value, the DMAC will check for receive descriptors. 
If no descriptors are available, the receive process returns to the suspended 
state and bit 7 of the DMAC_STATUS register (receive buffer unavailable - 
RU) is not set. A write to this register is only effective if the receive process 
is in the suspended state. A Read of this register will timeout and invalid 
data will be returned.
WO
-