AMD SC1201 manual Signal Descriptions, System Interface, Signal Name Ball No Type Description Mux

Signal Definitions 32579B

3.4Signal Descriptions

Information in the tables that follow may have duplicate information in multiple tables. Multiple references all contain identi- cal information.

3.4.1System Interface

Signal Name	Ball No.	Type	Description	Mux
CLKSEL1	AF3	I	Fast-PCI Clock Selects. These strap signals are used to	SOUT1
			set the internal Fast-PCI clock.
CLKSEL0	B8			RD#
			00 = 33.3 MHz
			01 = 48 MHz
			10 = 66.7 MHz
			11 = 33.3 MHz
			During system reset, an internal pull-down resistor of 100
			KΩ exists on these balls. An external pull-up or pull-down
			resistor of 1.5 KΩ must be used.
CLKSEL3	P30	I	Maximum Core Clock Multiplier. These strap signals	SYNC
			are used to set the maximum allowed multiplier value for
CLKSEL2	D29			SOUT2
			the core clock.
			During system reset, an internal pull-down resistor of 100
			KΩ exists on these balls. An external pull-up or pull-down
			resistor of 1.5 KΩ must be used.
BOOT16	C8	I	Boot ROM is 16 Bits Wide. This strap signal enables	ROMCS#
			the optional 16-bit wide Sub-ISA bus.
			During system reset, an internal pull-down resistor of 100
			KΩ exists on these balls. An external pull-up or pull-down
			resistor of 1.5 KΩ must be used.
LPC_ROM	D6	I	LPC ROM. This strap signal forces selecting of the LPC	PCICLK1
			bus and sets bit F0BAR1+I/O Offset 10h[15], LPC ROM
			Addressing Enable. It enables the SC1200/SC1201 pro-
			cessor to boot from a ROM connected to the LPC bus.
			During system reset, an internal pull-down resistor of 100
			KΩ exists on these balls. An external pull-up or pull-down
			resistor of 1.5 KΩ must be used.
TFT_PRSNT	P29	I	TFT Present. A strap used to select multiplexing of TFT	SDATA_OUT
			signals at power-up. Enables using TFT instead of Paral-
			lel Port, ACB1, and GPIO17.
			During system reset, an internal pull-down resistor of 100
			KΩ exists on these balls. An external pull-up or pull-down
			resistor of 1.5 KΩ must be used.
FPCI_MON	A4	I	Fast-PCI Monitoring. The strap on this ball forces selec-	PCICLK0
			tion of Fast-PCI monitoring signals. For normal operation,
			strap this signal low using a 1.5 KΩ resistor. The value of
			this strap can be read at MCR[30].
DID1	C6	I	Device ID. Together, the straps on these signals define	GNT1#
			the system-level chip ID.
DID0	C5	I		GNT0#
			The value of DID1 can be read in the MCR[29]. The
			value of DID0 can be read in the MCR[31].
			DID1 and DID0 should be connected to a 1.5 KΩ pull-
			down resistor to ensure a low level at power-up.
POR#	AH9	I	Power On Reset. POR# is the system reset signal gen-	---
			erated from the power supply to indicate that the system
			should be reset.
AMD Geode™ SC1200/SC1201 Processor Data Book				49