Two Port 10/100 Managed Ethernet Switch with 16-Bit Non-PCI CPU Interface

Datasheet

14.3.6Host MAC MII Access Register (HMAC_MII_ACC)

Offset:

6h

Size:

32 bits

This read/write register is used in conjunction with the Host MAC MII Data Register (HMAC_MII_DATA) to access the internal PHY registers. Refer to Section 14.4, "Ethernet PHY Control and Status Registers" for a list of accessible PHY registers and PHY address information.

BITS

DESCRIPTION

TYPE

DEFAULT

 

 

 

 

31:16

RESERVED

RO

-

 

 

 

 

15:11

PHY Address (PHY_ADDR)

R/W

00000b

 

This field must be loaded with the PHY address that the MII access is

 

 

 

intended for. A list default PHY addresses can be seen in Table 7.1. Refer

 

 

 

to Section 7.1.1, "PHY Addressing," on page 82 for additional information on

 

 

 

PHY addressing.

 

 

 

 

 

 

10:6

MII Register Index (MIIRINDA)

R/W

00000b

 

These bits select the desired MII register in the PHY.

 

 

 

 

 

 

5:2

RESERVED

RO

-

 

 

 

 

1

MII Write (MIIWnR)

R/W

0b

 

Setting this bit tells the PHY that this will be a write operation using the Host

 

 

 

MAC MII Data Register (HMAC_MII_DATA). If this bit is cleared, a read

 

 

 

operation will occur, packing the data in the Host MAC MII Data Register

 

 

 

(HMAC_MII_DATA).

 

 

 

 

 

 

0

MII Busy (MIIBZY)

R/W

0b

 

This bit must be polled to determine when the MII register access is

SC

 

 

complete. This bit must read a logical 0 before writing to this register or the

 

 

 

Host MAC MII Data Register (HMAC_MII_DATA).

 

 

 

The LAN driver software must set this bit in order for the

 

 

 

LAN9311/LAN9311i to read or write any of the MII PHY registers.

 

 

 

During a MII register access, this bit will be set, signifying a read or write

 

 

 

access is in progress. The MII data register must be kept valid until the Host

 

 

 

MAC clears this bit during a PHY write operation. The MII data register is

 

 

 

invalid until the Host MAC has cleared this bit during a PHY read operation.

 

 

 

 

 

 

SMSC LAN9311/LAN9311i

279

Revision 1.4 (08-19-08)

 

DATASHEET