Intel 6 SERIES CHIPSET - DATASHEET 01-2011 Datasheet page 542

13.10.1 GPIO_USE_SEL—GPIO Use Select Register
Offset Address: GPIOBASE + 00h
Default Value:
Lockable:
Bit
GPIO_USE_SEL[31:0] — R/W. Each bit in this register enables the corresponding
GPIO (if it exists) to be used as a GPIO, rather than for the native function.
0 = Signal used as native function.
1 = Signal used as a GPIO.
NOTES:
1.
2.
31:0
3.
4.
5.
6.
13.10.2 GP_IO_SEL—GPIO Input/Output Select Register
Offset Address: GPIOBASE +04h
Default Value:
Lockable:
Bit
31:0
542
B96BA1FFh
Yes
The following bits are always 1 because they are always unmultiplexed: 8, 15,
24, 27, and 28.
After a full reset (RSMRST#) all multiplexed signals in the resume and core
wells are configured as their default function. After only a PLTRST#, the GPIOs
in the core well are configured as their default function.
When configured to GPIO mode, the multiplexing logic will present the inactive
state to native logic that uses the pin as an input.
By default, all GPIOs are reset to the default state by CF9h reset except
GPIO24. Other resume well GPIOs' reset behavior can be programmed using
GP_RST_SEL registers.
Bit 29 can be configured to GPIO when SLP_LAN#/GPIO29 Select Soft-strap is
set to 1 (GPIO usage).
GPIO18, GPIO25, and GPIO26 are mobile only GPIOs.
F6FF6EFFh
Yes
GP_IO_SEL[31:0] — R/W.
When configured in native mode (GPIO_USE_SEL[n] is 0), writes to these bits have
no effect. The value reported in this register is undefined when programmed as
native mode.
0 = Output. The corresponding GPIO signal is an output.
1 = Input. The corresponding GPIO signal is an input.
LPC Interface Bridge Registers (D31:F0)
Attribute: R/W
Size: 32-bit
Power Well: Core for 0:7, 16:23,
Resume for 8:15, 24:31
Description
Attribute: R/W
Size: 32-bit
Power Well: Core for 0:7, 16:23,
Resume for 8:15, 24:31
Description
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