2 virtual phy registers synchronization, 5 register data, Register data – SMSC LAN9312 User Manual

Page 152: Section 10.2.4.5, Datasheet

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High Performance Two Port 10/100 Managed Ethernet Switch with 32-Bit Non-PCI CPU Interface

Datasheet

Revision 1.4 (08-19-08)

152

SMSC LAN9312

DATASHEET

The

Port x PHY Auto-Negotiation Advertisement Register (PHY_AN_ADV_x)

is written with the new

defaults as detailed in

Section 14.4.2.5, "Port x PHY Auto-Negotiation Advertisement Register

(PHY_AN_ADV_x)," on page 293

.

The

Port x PHY Special Modes Register (PHY_SPECIAL_MODES_x)

is written with the new defaults

as detailed in

Section 14.4.2.9, "Port x PHY Special Modes Register (PHY_SPECIAL_MODES_x)," on

page 300

.

The

Port x PHY Basic Control Register (PHY_BASIC_CONTROL_x)

is written with the new defaults

as detailed in

Section 14.4.2.1, "Port x PHY Basic Control Register (PHY_BASIC_CONTROL_x)," on

page 287

. Additionally, the Restart Auto-negotiation bit is set in this register. This re-runs the Auto-

negotiation using the new default values of the

Port x PHY Auto-Negotiation Advertisement Register

(PHY_AN_ADV_x)

register to determine the new Auto-negotiation results.

Note:

Each of these PHY registers is written in its entirety, overwriting any previously changed bits.

10.2.4.4.2

VIRTUAL PHY REGISTERS SYNCHRONIZATION

Some PHY register defaults are based on configuration straps. In order to maintain consistency
between the updated configuration strap registers and the Virtual PHY registers, the

Virtual PHY Auto-

Negotiation Advertisement Register (VPHY_AN_ADV)

,

Virtual PHY Special Control/Status Register

( V P H Y _ S P E C I A L _ C O N T R O L _ S TAT U S )

, a n d

V i r t u a l P H Y B a s i c C o n t r o l R e g i s t e r

(VPHY_BASIC_CTRL)

are written when the EEPROM Loader is run.

The

Virtual PHY Auto-Negotiation Advertisement Register (VPHY_AN_ADV)

is written with the new

defaults as detailed in

Section 14.2.8.5, "Virtual PHY Auto-Negotiation Advertisement Register

(VPHY_AN_ADV)," on page 252

.

The

Virtual PHY Special Control/Status Register (VPHY_SPECIAL_CONTROL_STATUS)

is written

with the new defaults as detailed in

Section 14.2.8.8, "Virtual PHY Special Control/Status Register

(VPHY_SPECIAL_CONTROL_STATUS)," on page 257

.

The

Virtual PHY Basic Control Register (VPHY_BASIC_CTRL)

is written with the new defaults as

detailed in

Section 14.2.8.1, "Virtual PHY Basic Control Register (VPHY_BASIC_CTRL)," on page 246

.

Additionally, the Restart Auto-negotiation bit is set in this register. This re-runs the Auto-negotiation
using the new default values of the

Virtual PHY Auto-Negotiation Advertisement Register

(VPHY_AN_ADV)

register to determine the new Auto-negotiation results.

Note:

Each of these VPHY registers is written in its entirety, overwriting any previously changed bits.

10.2.4.4.3

LED AND MANUAL FLOW CONTROL REGISTER SYNCHRONIZATION

Since the defaults of the

LED Configuration Register (LED_CFG)

,

Port 1 Manual Flow Control Register

(MANUAL_FC_1)

,

Port 2 Manual Flow Control Register (MANUAL_FC_2)

, and

Port 0(Host MAC)

Manual Flow Control Register (MANUAL_FC_MII)

are based on configuration straps, the EEPROM

Loader reloads these registers with their new default values.

10.2.4.5

Register Data

Optionally following the configuration strap values, the EEPROM data may be formatted to allow
access to the LAN9312 parallel, directly writable registers. Access to indirectly accessible registers
(e.g. Switch Engine registers, etc.) is achievable with an appropriate sequence of writes (at the cost
of EEPROM space).

This data is first preceded with a Burst Sequence Valid Flag (EEPROM byte 12). If this byte has a
value of A5h, the data that follows is recognized as a sequence of bursts. Otherwise, the EEPROM
Loader is finished, will go into a wait state, and clear the EPC_BUSY bit in the

EEPROM Command

Register (E2P_CMD)

. This can optionally generate an interrupt.

The data at EEPROM byte 13 and above should be formatted in a sequence of bursts. The first byte
is the total number of bursts. Following this is a series of bursts, each consisting of a starting address,
count, and the count x 4 bytes of data. This results in the following formula for formatting register data:

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