Intel IXP46X manual MII NPE B Signal Recommendations Sheet 2 of, MII NPE C Signal Recommendations

Intel® IXP45X and Intel® IXP46X Product Line of Network Processors—General Hardware Design Considerations

Table 9.			MII NPE B Signal Recommendations (Sheet 2 of 2)
				Input/	Pull
		Name			Up/	Recommendations
				Output
					Down
						Collision Detect.
	ETHB_COL			I	Yes	If operating in a full duplex mode and there is no requirement to use the Collision
						Detect signal, then the pin must be pulled low with a 10-KΩresistor.
						Carrier Sense.
	ETHB_CRS			I	Yes	When this interface/signal is enabled and is not being used in a system design, the
						interface/signal should be pulled high with a 10-KΩresistor.
	Notes:
	1.	Features disabled/enabled by Soft Fuse must be done during the boot-up sequence. A feature cannot be enabled after
		being disabled without asserting a system reset.
	2.	Features disabled by a specific part number, do not require pull-ups or pull-downs. Therefore, all pins can be left
		unconnected.
	3.	Features enabled by a specific part number — and required to be Soft Fuse-disabled, as stated in Note 1 — only require
		pull-ups or pull-downs in the clock-input signals.

Table 10.			MII NPE C Signal Recommendations
		Name		Input/	Pull
					Up/	Recommendations
				Output
					Down
						Transmit Clock.
	ETHC_TXCLK			I	Yes	When this interface/signal is enabled and is not being used in a system design, the
						interface/signal should be pulled high with a 10-KΩresistor.
	ETHC_TXDATA[3:0]			O	No	Transmit Data.
	ETHC_TXEN			O	No	Transmit Enable.
						Receive Clock.
	ETHC_RXCLK			I	Yes	When this interface/signal is enabled and is not being used in a system design, the
						interface/signal should be pulled high with a 10-KΩresistor.
						Receive Data.
	ETHC_RXDATA[3:0]			I	Yes	When this interface/signal is enabled and is not being used in a system design, the
						interface/signal should be pulled high with a 10-KΩresistor.
						Receive Data Valid.
	ETHC_RXDV			I	Yes	When this interface/signal is enabled and is not being used in a system design, the
						interface/signal should be pulled high with a 10-KΩresistor.
						Collision Detect.
	ETHC_COL			I	Yes	If operating in a full duplex mode and there is no requirement to use the Collision
						Detect signal, then the pin must be pulled low with a 10-KΩresistor.
						Carrier Sense.
	ETHC_CRS			I	Yes	When this interface/signal is enabled and is not being used in a system design, the
						interface/signal should be pulled high with a 10-KΩresistor.
	Notes:
	1.	Features disabled/enabled by Soft Fuse must be done during the boot-up sequence. A feature cannot be enabled after
		being disabled without asserting a system reset.
	2.	Features disabled by a specific part number, do not require pull-ups or pull-downs. Therefore, all pins can be left
		unconnected.
	3.	Features enabled by a specific part number — and required to be Soft Fuse-disabled, as stated in note 1 — only require
		pull-ups or pull-downs in the clock-input signals.

Intel® IXP45X and Intel® IXP46X Product Line of Network Processors
HDD	February 2007
32	Document Number: 305261; Revision: 004