LAN9420 Datasheet, PDF (35/171 Pages) SMSC Corporation – Single-Chip Ethernet Controller with HP Auto-MDIX Support and PCI Interface

Single-Chip Ethernet Controller with HP Auto-MDIX Support and PCI Interface
Datasheet
EWDS (Erase/Write Disable): After issued, the EEPROM will ignore erase and write commands. To
re-enable erase/write operations issue the EWEN command.
tCSL
EECS
EECLK
EEDIO (OUTPUT)
1
0
0
0
0
EEDIO (INPUT)
Figure 3.10 EEPROM EWDS Cycle
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: 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.
t_CSL
EECS
EECLK
EEDIO (OUTPUT)
1
0
0
1
1
EEDIO (INPUT)
Figure 3.11 EEPROM EWEN Cycle
SMSC LAN9420/LAN9420i
35
DATASHEET
Revision 1.6 (07-18-11)