SMSC LAN9420, LAN9420i NUM, NUM, PINS, NAME, TYPE, PINS, NAME, TYPE, BUFFER, SYMBOL, BUFFER, SYMBOL, DESCRIPTION, DESCRIPTION, AutoMDIX Enable:, nLED1 (Speed Indicator):

Single-Chip Ethernet Controller with HP Auto-MDIX Support and PCI Interface

Datasheet

Table 2.3 GPIO and LED Pins

NUM				BUFFER
PINS	NAME	SYMBOL		TYPE	DESCRIPTION
	General	GPIO0		IS/O12/	General Purpose I/O data 0: This general-purpose pin is
	Purpose I/O			OD12	fully programmable as either push-pull output, open-drain
	data 0				output or input by writing the GPIO_CFG configuration
					register in the SCSR. GPIO pins are Schmitt-triggered
1					inputs.
	nLED1 (Speed	nLED1		OD12	nLED1 (Speed Indicator): This pin can also function as
	Indicator)				the Ethernet speed indicator LED and is driven low when
					the operating speed is 100Mbs, during auto-negotiation,
					and when the cable is disconnected. This pin is driven
					high only during 10Mbs operation.
	General	GPIO1		IS/O12/	General Purpose I/O data 1: This general-purpose pin is
	Purpose I/O			OD12	fully programmable as either push-pull output, open-drain
	data 1				output or input by writing the GPIO_CFG configuration
					register in the SCSR. GPIO pins are Schmitt-triggered
					inputs.
	nLED2 (Link &	nLED2		OD12	nLED2 (Link & Activity Indicator): This pin can also
1	Activity				function as the Ethernet Link and Activity Indicator LED
	Indicator)				and is driven low (LED on) when LAN9420/LAN9420i
					detects a valid link. This pin is pulsed high (LED off) for
					80mS whenever transmit or receive activity is detected.
					This pin is then driven low again for a minimum of 80mS,
					after which time it will repeat the process if TX or RX
					activity is detected. Effectively, LED2 is activated solid for
					a link. When transmit or receive activity is sensed, LED2
					will flash as an activity indicator.
	General	GPIO2		IS/O12/	General Purpose I/O data 2: This general-purpose pin is
	Purpose I/O			OD12	fully programmable as either push-pull output, open-drain
	data 2				output or input by writing the GPIO_CFG configuration
1					register in the SCSR. GPIO pins are Schmitt-triggered
					inputs.
	nLED3 (Full-	nLED3		OD12	nLED3 (Full-Duplex Indicator): This pin can also
	Duplex				function as the Ethernet Full-Duplex Indicator LED and is
	Indicator)				driven low when the link is operating in full-duplex mode.
			Table 2.4 Configuration Pins
NUM				BUFFER
PINS	NAME	SYMBOL		TYPE	DESCRIPTION
1	AutoMDIX	AUTOMDIX_EN		IS	AutoMDIX Enable: Enables Auto-MDIX. Pull high or
	Enable			(PU)	leave unconnected to enable Auto-MDIX, pull low to
					disable Auto-MDIX.

Revision 1.22 (09-25-08)	18	SMSC LAN9420/LAN9420i
	DATASHEET