8 mdio register overview, Table 142. mdio single command ($0x680), Mdio register overview – Intel IXF1104 User Manual
Page 211: Mdio single command ($0x680), Mdio single read and write data ($0x681)

Intel
®
IXF1104 4-Port Gigabit Ethernet Media Access Controller
211
Datasheet
Document Number: 278757
Revision Number: 009
Revision Date: 27-Oct-2005
8.4.8
MDIO Register Overview
through
provide an overview of the MDIO registers.
Table 142. MDIO Single Command ($0x680)
Bit
Name
Description
Type
1
Default
Register Description: Gives the CPU the ability to perform single MDIO read and write
accesses to the external PHY for ports that are configured in copper mode.
0x00010000
31:21
Reserved
Reserved
RO
00000000000
20
MDIO Command
Performs the MDIO operation. Cleared when
done.
0 = MDIO ready, operation complete
1 = Perform operation
R/W
0
19:18
Reserved
Reserved
RO
00
17:16
OP Code
MDIO Op Code; two bits identify operation to be
performed:
00 = Reserved
01 = Write operation (as defined in IEEE 802.3,
clause 22.2.4.5)
10 = Read operation (as defined in IEEE 802.3,
clause 22.2.4.5)
11 = Reserved
R/W
01
15:10
Reserved
Reserved
RO
000000
9:8
PHY Address
Sets bits 1:0 of the external PHY address. Bits 4:2
of the PHY address are fixed at 000.
R/W
00
7:5
Reserved
Reserved
RO
000
4:0
REG Address
Five-bit address to one among 32 registers in an
addressed PHY device.
R/W
00000
1. RO = Read Only, No clear on Read; R = Read, Clear on Read; W = Write only; R/W = Read/Write, No
clear; R/W/C = Read/Write, Clear on Write
Table 143. MDIO Single Read and Write Data ($0x681)
Bit
Name
Description
Type
1
Default
Register Description: MDIO read and write data.
0x00000000
31:16
MDIO Read Data
MDIO Read data from external device.
RO
0x0000
15:0
MDIO Write Data
MDIO Write data to external device.
R/W
0x0000
1. RO = Read Only, No clear on Read; R = Read, Clear on Read; W = Write only; R/W = Read/Write, No
clear; R/W/C = Read/Write, Clear on Write