4 general purpose input/output signals, General purpose input/output signals, 13 gpio signal descriptions – Intel D15343-003 User Manual
Page 38
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Intel
®
854 Graphics Memory Controller Hub (GMCH)
38
D15343-003
3.5.4
General Purpose Input/Output Signals
Table 13.
GPIO Signal Descriptions
GPIO I/F Total
Type
Comments
RSTIN#
I
CMOS
Reset:
Primary Reset, Connected to PCIRST# of ICH4-M.
PWROK
I
CMOS
Power OK
: Indicates that power to GMCH is stable.
EXTTS_0
I
CMOS
External Thermal Sensor Input:
This signal is an active low input to the
GMCH and is used to monitor the thermal condition around the system memory
and is used for triggering a read throttle. The GMCH can be optionally
programmed to send a SERR, SCI, or SMI message to the ICH4-M upon the
triggering of this signal.
LCLKCTLA
O
CMOS
SSC Chip Clock Control:
Can be used to control an external clock chip with
SSC control.
LCLKCTLB
O
CMOS
SSC Chip Data Control:
Can be used to control an external clock chip for
SSC control.
DDCACLK
I/O
CMOS
CRT DDC Clock:
This signal is used as the DDC clock signal between the
CRT monitor and the GMCH.
DDCADATA
I/O
CMOS
CRT DDC Data:
This signal is used as the DDC data signal between the CRT
monitor and the GMCH.
MI2CCLK
I/O
DVO
DVO I2C Clock:
This signal is used as the I2C_CLK for a digital display (i.e.
TV-Out Encoder, TMDS transmitter). This signal is tri-stated during a hard
reset.
MI2CDATA
I/O
DVO
DVO I2C Data:
This signal is used as the I2C_DATA for a digital display (i.e.
TV-Out Encoder, TMDS transmitter). This signal is tri-stated during a hard
reset.
MDVICLK
I/O
DVO
DVI DDC Clock:
This signal is used as the DDC clock for a digital display
connector (that is, primary digital monitor). This signal is tri-stated during a hard
reset.
MDVIDATA
I/O
DVO
DVI DDC Data:
The signal is used as the DDC data for a digital display
connector (that is, the primary digital monitor). This signal is tri-stated during a
hard reset.
MDDCDATA
I/O
DVO
DVI DDC Clock:
The signal is used as the DDC data for a digital display
connector (that is, the secondary digital monitor). This signal is tri-stated during
a hard reset.
MDDCCLK
I/O
DVO
DVI DDC Data:
The signal is used as the DDC clock for a digital display
connector (that is, the secondary digital monitor). This signal is tri-stated during
a hard reset.