82801CA Datasheet, PDF (48/521 Pages) Intel Corporation – I/O Controller Hub 3-S (ICH3-S)

Signal Description
2.12 SMBus Interface
Table 2-12. SM Bus Interface Signals
Name
SMBDATA
SMBCLK
SMBALERT#/
GPIO[11]
Type
I/OD
I/OD
I
Description
SMBus Data: External pull-up is required.
SMBus Clock: External pull-up is required.
SMBus Alert: This signal is used to wake the system or generate SMI#. If not
used for SMBALERT#, it can be used as a GPI.
2.13 System Management Interface
Table 2-13. System Management Interface Signals
Name
INTRUDER#
SMLINK[1:0]
Type
I
I/OD
Description
Intruder Detect: 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.
System Management Link: SMBus link to 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.
2.14 Real Time Clock Interface
Table 2-14. Real Time Clock Interface
Name
RTCX1
RTCX2
Type
Description
Special
Special
Crystal Input 1: Connected to the 32.768 kHz crystal. If no external crystal is
used, then RTCX1 can be driven with the desired clock rate.
Crystal Input 2: Connected to the 32.768 kHz crystal. If no external crystal is
used, then RTCX2 should be left floating.
48
Intel^® 82801CA ICH3-S Datasheet