MiTAC 7521 PLUS/N Auxok, Batok, OSC32KHI, Pwrok, Acbitclk, Acreset#, Acsdout, Acsync, Spdif, Eecs

7521Plus / N N/B MAINTENANCE

5.Pin Descriptions Of Major Components

5.2SiS630S Slot 1/Socket 370 2D/3D Ultra-AGP™ Single Chipset

RTC Interface

Name	Tolerance	Power	Type	Description
		Plane	Attr
AUXOK	1.8V	RTC	I	Auxiliary Power OK : This signal is supplied from
				the power source of resume well. It is also used to
				reset the logic in resume power well. If there is no
				auxiliary power source on the system, this pin should
				be tied together with PWROK.
BATOK	1.8V	RTC	I	Battery Power OK: When the internal RTC is
				enabled, this signal is used to indicate that the power
				of RTC well is stable. It is also used to reset the logic
				in RTC well. If the internal RTC is disabled, this pin
				should be tied low.
OSC32KHI	1.8V	RTC	I	RTC 32.768 KHz Input : When internal RTC is
				enabled, this pin provides the 32.768 KHz clock
				signal from external crystal or oscillator.
OSC32KHO	<1.8V	RTC	O	RTC 32.768 KHz Output : When internal RTC is
				enabled, this pin should be connected with the other
				end of the 32.768 KHz crystal or left unconnected if
				an oscillator is used.
PWROK	1.8V	RTC	I	Main Power OK : A high-level input to this signal
				indicates the power being supplied to the system is in
				stable operating state. During the period of PWROK
				being low, CPURST and PCIRST# will all be
				asserted until after PWROK goes high for 24 ms.

AC’97 interface

Name	Tolerance	Power	Type	Description
		Plane	Attr
AC_BITCLK	3.3V/5V	MAIN	I	AC’97Bit Clock : This signal is a 12.288MHz
				serial data clock, which is generated by primary
				Codec.
AC_RESET#	3.3V	AUX	O	AC’97 Reset : Hardware reset signal for external
				Codecs.
AC_SDIN[1:0]	3.3V/5V	AUX	I	AC’97 Serial Data input : Serial data input from
				primary Codec and secondary Codec.
AC_SDOUT	3.3V	MAIN	O	AC’97 Serial Data output : Serial data output to
				Codecs.
AC_SYNC	3.3V	MAIN	O	AC’97 Syncronization : This is a 48KHz signal,
				which is used to syncronize the Codecs.
SPDIF	3.3V/5V	MAIN	O	S/PDIF Transmitter Output
GPIO7			I/O/OD	General Purpose Input/Output 7 :
				Refer to GPIO description.

Fast Ethernet and Homenetworking interface

Name	Tolerance	Power	Type	Description
		Plane	Attr
EECS	3.3V	AUX	O	Serial EEPROMChip Select : This enables the EEPROMduring loading of
				the Ethernet configuration data.
EEDI	3.3V	AUX	O	Serial EEPROMData Input : During serial EEPROMaccess cycle, the
				SiS630 will use this pin to serially write OP codes, addresses and data into the
				serial EEPROM.
EEDO	3.3V/5V	AUX	I	Serial EEPROMData Output : During serial EEPROMaccess cycle, the
GPIO3			I/O/OD	SiS630 will read the contents of the EEPROMserially through this pin.
				Requires external pull-up resistor.
				General Purpose Input/Output 3 : Refer to GPIO description.
EESK	3.3V	AUX	O	Serial EEPROMClock : This pin provides the clock for the serial EEPROM.
OSC25MHI	3.3V	AUX	I	PHY25MHz Clock Input : This pin is supplied the 25MHz clock signal input
				fromthe external crystal or an oscillator.
PLEDO#	3.3V	AUX	OD	Programmable LED Output :
OC3#			O	(A)Select 10/100Mbps LANMode: This pin is used as an LINK/ACTIVITY
GPIO8			I/O/OD	indication output.
				(B)Select Home Networking Mode: This pin is also an LINK/ACTIVITY
				indication output.
				OC3# : When this pin is configured as OC3#, it can
				detects USB Port 3 over current condition.
				General Purpose Input/Output 8 : Refer to GPIO description.
REXT		AUX	I	Transmit Current Set : An external resistor connected between this pin and
				GND will set the output current level for the twisted pair outputs.
TPIP		AUX	I	Twisted Pair Receive Positive Input
TPIN		AUX	I	Twisted Pair Receive Negative Input
TPOP		AUX	O	Twisted Pair Transmit Positive Output
TPON		AUX	O	Twisted Pair Transmit Negative Output
HRTXRXP		AUX	I/O	Twisted Pair Transmit / Receive Positive Data
HRTXRXN		AUX	I/O	Twisted Pair Transmit / Receive Negative Data

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