8170 N/B MAINTENANCE

5.3 Intel 82801BA(I/O Controller HUB )

System Management Interface Signals

Name

Type

Description

INTRUDER#

I

Intruder Detect: This signal can be set to disable system if box

 

 

detected open. This signal’s status is readable, so it can be used like a

 

 

GPI if the Intruder Detection is not needed.

SMLINK[1:0]

I/OD

System Management Link: These signals are an SMBus link to an

 

 

optional external system management ASIC or LAN controller.

 

 

External pull-ups are required.

 

 

Note:

 

 

that SMLINK[0] corresponds to an SMBus Clock signal and

 

 

SMLINK[1] corresponds to an SMBus Data signal.

Real Time Clock Interface

Name

Type

Description

RTCX1

Special

Crystal Input 1: This signal is connected to the 32.768 KHz crystal.

 

 

If no external crystal is used, then RTCX1 can be driven with the

 

 

desired clock rate.

RTCX2

Special

Crystal Input 2: This signal is connected to the 32.768 KHz crystal.

 

 

If no external crystal is used, then RTCX2 should be left floating.

Other Clocks

Name

Type

Description

CLK14

I

Oscillator Clock: CLK14 is used for 8254 timers and runs at

 

 

14.31818 MHz.

 

 

82801BA ICH2: This clock is permitted to stop during S3 (or lower)

 

 

states.

 

 

82801BAM ICH2-M:This clock is permitted to stop during S1 (or

 

 

lower) states.

CLK48

I

48 MHz Clock: CLK48 is used to for the USB controller and runs at

 

 

48 MHz.

 

 

82801BA ICH2: This clock is permitted to stop during S3 (or lower)

 

 

states.

 

 

82801BAM ICH2-M:This clock is permitted to stop during S1 (or

 

 

lower) states.

CLK66

I

66 MHz Clock: CLK66 is used to for the hub interface and runs at 66

 

 

MHz.

 

 

82801BA ICH2: This clock is permitted to stop during S3 (or lower)

 

 

states.

 

 

82801BAM ICH2-M:This clock is permitted to stop during S1 (or

 

 

lower) states.

Miscellaneous Signals

Name

Type

Description

SPKR

O

Speaker: The SPKR signal is the output of counter 2 and is internally

 

 

"ANDed" with Port 61h bit 1 to provide Speaker Data Enable. This

 

 

signal drives an external speaker driver device, which in turn drives

 

 

the system speaker. Upon PCIRST#, its output state is 1.

 

 

Note:

 

 

SPKR is sampled at the rising edge of PWROK as a functional strap.

RTCRST#

I

RTC Reset: When asserted, this signal resets register bits in the RTC

 

 

well and sets the RTC_PWR_STS bit (bit 2 in GEN_PMCON3

 

 

register). Note:

 

 

Clearing CMOS in an ICH2-based platform can be done by using a

 

 

jumper on RTCRST# or GPI, or using SAFEMODE strap.

 

 

Implementations should not attempt to clear CMOS by using a

 

 

jumper to pull VccRTC low.

TP0

I

Test Point (82801BA ICH2): This signal must have an external

(ICH2 0nly)

 

pull-up to VccSus3_3.

FS0

I

Functional Strap: This signal is reserved for future use. There is an

 

 

internal pullup resistor on this signal.

AC’97 Link Signals

Name

Type

Description

AC_RST#

O

AC97 Reset: Master H/W reset to external Codec(s)

 

 

 

AC_SYNC

O

AC97 Sync: 48 KHz fixed rate sample sync to the Codec(s)

AC_BIT_CLK

I

AC97 Bit Clock: 12.288 MHz serial data clock generated by the

 

 

external Codec(s). See Note.

AC_SDOUT

O

AC97 Serial Data Out: Serial TDM data output to the Codec(s)

 

 

Note:

 

 

AC_SDOUT is sampled at the rising edge of PWROK as a functional

 

 

strap..

AC_SDIN[1:0]

I

AC97 Serial Data In 0: Serial TDM data inputs from the Codecs.

 

 

See Note.

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