lan9221 Standard Microsystems Corp., lan9221 Datasheet - Page 104

• Manufacturer Part Number: lan9221
• Description: High-performance 16-bit Non-pci 10/100 Ethernet Controller With Variable Voltage I/o
• Manufacturer: Standard Microsystems Corp.

Revision 2.6 (12-04-08)
30-28
27-10
BITS
EPC command. This field is used to issue commands to the EEPROM
controller. The EPC will execute commands when the EPC Busy bit is set.
A new command must not be issued until the previous command completes.
This field is encoded as follows:
READ (Read Location): This command will cause a read of the EEPROM
location pointed to by EPC Address. The result of the read is available in
the E2P_DATA register.
EWDS (Erase/Write Disable): After issued, the EEPROM will ignore erase
and write commands. To re-enable erase/write operations issue the EWEN
command.
EWEN (Erase/Write Enable): Enables the EEPROM for erase and write
operations. The EEPROM will allow erase and write operations until the
Erase/Write Disable command is sent, or until power is cycled.
Note:
WRITE (Write Location): If erase/write operations are enabled in the
EEPROM, this command will cause the contents of the E2P_DATA register
to be written to the EEPROM location selected by the EPC Address field.
WRAL (Write All): If erase/write operations are enabled in the EEPROM,
this command will cause the contents of the E2P_DATA register to be
written to every EEPROM memory location.
ERASE (Erase Location): If erase/write operations are enabled in the
EEPROM, this command will erase the location selected by the EPC
Address field.
ERAL (Erase All): If erase/write operations are enabled in the EEPROM,
this command will initiate a bulk erase of the entire EEPROM.
RELOAD (MAC Address Reload): Instructs the EEPROM controller to
reload the MAC address from the EEPROM. If a value of 0xA5 is not found
in the first address of the EEPROM, the EEPROM is assumed to be un-
programmed and MAC Address Reload operation will fail. The “MAC
Address Loaded” bit indicates a successful load of the MAC address.
Reserved.
The EEPROM device will power-up in the erase/write-disabled
state. Any erase or write operations will fail until an Erase/Write
Enable command is issued.
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DESCRIPTION
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DATASHEET
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High-Performance 16-bit Non-PCI 10/100 Ethernet Controller with Variable Voltage I/O
OPERATION
ERASE
WRITE
Reload
EWDS
EWEN
WRAL
READ
ERAL
TYPE
R/W
RO
SMSC LAN9221/LAN9221i
DEFAULT
Datasheet
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