SMSC LAN9420 - Manual (Page 17)

Single-Chip Ethernet Controller with HP Auto-MDIX Support and PCI Interface
Datasheet
SMSC LAN9420/LAN9420i 17 Revision 1.22 (09-25-08)
DATASHEET
Note 2.1 This pin is used for factory testing and is latched on power up. This pin is pulled high
through an internal resistor and must not be pulled low externally. This pin must be
augmented with an external resistor when connected to a load. The value of the resistor
must be such that the pin reaches its valid level before de-assertion of PCInRST following
power up. The “IS” input buffer type is enabled only during power up. The “IS” input buffer
type is disabled at all other times.
Table 2.2 EEPROM
NUM
PINS
NAME SYMBOL
BUFFER
TYPE DESCRIPTION
1
EEPROM Data EEDIO IS/O8 EEPROM Data: This bi-directional pin can be connected
to an optional serial EEPROM DIO.
GPO3 GPO3 O8 General Purpose Output 3: This pin can also function
as a general purpose output. The EECS pin is deasserted
so as to never unintentionally access the serial EEPROM.
TX_EN TX_EN O8 TX_EN Signal Monitor: This pin can also be configured
to monitor the TX_EN signal on the internal MII port. The
EECS pin is deasserted so as to never unintentionally
access the serial EEPROM.
TX_CLK TX_CLK O8 TX_CLK Signal Monitor: This pin can also be configured
to monitor the TX_CLK signal on the internal MII port.
The EECS pin is deasserted so as to never
unintentionally access the serial EEPROM.
1
EEPROM Chip
Select
EECS O8 Serial EEPROM Chip Select.
1
EEPROM
Clock
EECLK IS/O8
(PU)
Note 2.1
EEPROM Clock: Serial EEPROM Clock pin
GPO4 GPO4 O8 General Purpose Output 4: This pin can also function
as a general purpose output. The EECS pin is deasserted
so as to never unintentionally access the serial EEPROM.
RX_DV RX_DV O8 RX_DV Signal Monitor: This pin can also be configured
to monitor the RX_DV signal on the internal MII port. The
EECS pin is deasserted so as to never unintentionally
access the serial EEPROM.
RX_CLK RX_CLK O8 RX_CLK Signal Monitor: This pin can also be
configured to monitor the RX_CLK signal on the internal
MII port. The EECS pin is deasserted so as to never
unintentionally access the serial EEPROM.