SMSC LAN9420 - Manual (Page 148)

Single-Chip Ethernet Controller with HP Auto-MDIX Support and PCI Interface
Datasheet
Revision 1.22 (09-25-08) 148 SMSC LAN9420/LAN9420i
DATASHEET
4.5.13 PHY Special Control/Status
Note 4.6 Bit 6 of this register must be set to ‘1’ for write operations.
Index (In Decimal): 31 Size: 16 bits
BITS DESCRIPTION TYPE DEFAULT
15:13 RESERVED RO -
12 Autodone
Auto-negotiation done indication:
0 = Auto-negotiation is not done or disabled (or not active)
1 = Auto-negotiation is done RO 0
11:5 RESERVED
Write as 0000010b, ignore on read.
Note 4.6 -
4:2 Speed Indication
HCDSPEED value:
[001b] = 10Mbps half-duplex
[101b] = 10Mbps full-duplex
[010b] = 100BASE-TX half-duplex
[110b] = 100BASE-TX full-duplex RO 000b
1:0 RESERVED RO -