LM3S6753 Datasheet, PDF (468/625 Pages) Texas Instruments – Stellaris LM3S6753 Microcontroller

Ethernet Controller
Register 20: Ethernet PHY Management Register 4 – Auto-Negotiation
Advertisement (MR4), address 0x04
This register provides the advertised abilities of the Ethernet Controller used during auto-negotiation.
Bits 8:5 represent the Technology Ability Field bits. This field can be overwritten by software to
auto-negotiate to an alternate common technology. Writing to this register has no effect until
auto-negotiation is re-initiated by setting the RANEG bit in the MR0 register.
Ethernet PHY Management Register 4 – Auto-Negotiation Advertisement (MR4)
Base 0x4004.8000
Address 0x04
Type R/W, reset 0x01E1
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
NP
reserved
RF
reserved
A3
A2
A1
A0
S
Type RO
RO
R/W
RO
RO
RO
RO
R/W
R/W
R/W
R/W
RO
RO
RO
RO
RO
Reset
0
0
0
0
0
0
0
1
1
1
1
0
0
0
0
1
Bit/Field
15
14
13
12:9
8
7
6
Name
NP
reserved
RF
reserved
A3
A2
A1
Type
RO
RO
R/W
RO
R/W
R/W
R/W
Reset
0
0
0
0x0
1
1
1
Description
Next Page
When set, this bit indicates the Ethernet Controller is capable of Next
Page exchanges to provide more detailed information on the PHY layer’s
capabilities.
Software should not rely on the value of a reserved bit. To provide
compatibility with future products, the value of a reserved bit should be
preserved across a read-modify-write operation.
Remote Fault
When set, this bit indicates to the link partner that a Remote Fault
condition has been encountered.
Software should not rely on the value of a reserved bit. To provide
compatibility with future products, the value of a reserved bit should be
preserved across a read-modify-write operation.
Technology Ability Field[3]
When set, this bit indicates that the Ethernet Controller supports the
100Base-TX full-duplex signaling protocol. If software wants to ensure
that this mode is not used, this bit can be cleared and auto-negotiation
re-initiated with the RANEG bit in the MR0 register.
Technology Ability Field[2]
When set, this bit indicates that the Ethernet Controller supports the
100Base-TX half-duplex signaling protocol. If software wants to ensure
that this mode is not used, this bit can be cleared and auto-negotiation
re-initiated with the RANEG bit in the MR0 register.
Technology Ability Field[1]
When set, this bit indicates that the Ethernet Controller supports the
10BASE-T full-duplex signaling protocol. If software wants to ensure
that this mode is not used, this bit can be cleared and auto-negotiation
re-initiated with the RANEG bit in the MR0 register..
468
April 05, 2010
Texas Instruments-Production Data