Register Map
1424
SPRUHE8E – October 2012 – Revised November 2019
Copyright © 2012–2019, Texas Instruments Incorporated
M3 Ethernet Media Access Controller (EMAC)
19.5 Register Map
lists the EMAC and MII Management registers. The MAC register addresses given are relative
to the Ethernet base address of 0x4004.8000. The MII Management registers are accessed using the
MACMCTL register. Note that the EMAC clocks must be enabled before the registers can be
programmed. There must be a delay of three system clocks after the Ethernet MAC clock is enabled
before any MAC registers are accessed.
The IEEE 802.3 standard specifies a register set for controlling and gathering status from the PHY layer.
The registers are collectively known as the MII Management registers and are detailed in Section 22.2.4 of
the IEEE 802.3 specification.
also lists these MII Management registers. All addresses given
are absolute and are written directly to the REGADR field of the Ethernet MAC Management Control
(MACMCTL) register. The format of registers 0 to 15 are defined by the IEEE specification and are
common to all PHY layer implementations. The only variance allowed is for features that may or may not
be supported by a specific PHY implementation. Registers 16 to 31 are vendor-specific registers, used to
support features that are specific to a vendor's PHY implementation.
PHY registers MR0 – MR6 are not located on the microcontroller. These registers are located on IEEE
802.3 compliant Ethernet external PHYs. These registers are defined for software ease of use. See
registers MACMCTL, MACMTXD, and MACMRXD for instructions on how to read and write to the
registers on an external Ethernet PHY.
Table 19-2. Ethernet Register Map
Offset
Name
Type
Reset
Description
0x000
MACRIS/MACIACK
R/W1C
0x0000.0000
Ethernet MAC Raw Interrupt
Status/Acknowledge
0x004
MACIM
R/W
0x0000.007F
Ethernet MAC Interrupt Mask
0x008
MACRCTL
R/W
0x0000.0008
Ethernet MAC Receive Control
0x00C
MACTCTL
R/W
0x0000.0000
Ethernet MAC Transmit
Control
0x010
MACDATA
R/W
0x0000.0000
Ethernet MAC Data
0x014
MACIA0
R/W
0x0000.0000
Ethernet MAC Individual
Address 0
0x018
MACIA1
R/W
0x0000.0000
Ethernet MAC Individual
Address 1
0x01C
MACTHR
R/W
0x0000.003F
Ethernet MAC Threshold
0x020
MACMCTL
R/W
0x0000.0000
Ethernet MAC Management
Control
0x024
MACMDV
R/W
0x0000.0080
Ethernet MAC Management
Divider
0x028
MACMAR
R/W
0X0
Ethernet MAC Management
Address Register
0x02C
MACMTXD
R/W
0x0000.0000
Ethernet MAC Management
Transmit Data
0x030
MACMRXD
R/W
0x0000.0000
Ethernet MAC Management
Receive Data
0x034
MACNP
RO
0x0000.0000
Ethernet MAC Number of
Packets
0x038
MACTR
R/W
0x0000.0000
Ethernet MAC Transmission
Request
0x03C
MACTS
R/W
0x0000.0000
Ethernet MAC Timer Support
0x040
-
R/W
0x0000.0000
Reserved
0x044
-
R/W
0x0000.0000
Reserved
MII Management (Accessed through the MACMCTL register)
-
MR0
R/W
0x1000
Ethernet PHY Management
Register 0 – Control
-
MR1
RO
0x7809
Ethernet PHY Management
Register 1 – Status