
82801AA and 82801AB Datasheet
8-75
LPC Interface Bridge Registers (D31:F0)
8.10
General Purpose I/O Registers (D31:F0)
The control for the general purpose I/O signals is handled through a separate 64-byte I/O space.
The base offset for this space is selected by the GPIO_BAR register.
Table 8-12
summarizes the
ICH GPIO implementation.
Table 8-12. Summary of GPIO Implementation (Sheet 1 of 3)
GPIO
Type
Alternate
Function (1)
Power
Well
Notes
GPIO[0]
Input
Only
REQ[A]#
Core
GPIO_USE_SEL bit 0 enables REQ/GNT[A]# pair.
Input active status read from GPE1_STS register
bit 0.
Input active high/low set through GPI_INV register
bit 0.
GPIO[1]
Input
Only
REG[B]#or
REQ[5]# on
ICH
(82801AA)
REQ[B]# only
on ICH0
(82801AB)
Core
GPIO_USE_SEL bit 1 enables REQ/GNT[B]# pair.
Input active status read from GPE1_STS register
bit 1.
Input active high/low set through GPI_INV register
bit 1.
GPIO[2]
N/A
N/A
N/A
Not Implemented
GPIO[3]
N/A
N/A
N/A
Not Implemented
GPIO[4]
N/A
N/A
N/A
Not Implemented
GPIO[5]
Input
Only
Unmuxed
Core
Input active status read from GPE1_STS register
bit 5.
Input active high/low set through GPI_INV register
bit 5.
GPIO[6]
Input
Only
Unmuxed
Core
Input active status read from GPE1_STS register
bit 6.
Input active high/low set through GPI_INV register
bit 6.
GPIO[7]
Input
Only
PERR# on
ICH
(82801AA)
Unmuxed on
ICH0
(82801AB)
Core
Input active status read from GPE1_STS register
bit 7.
Input active high/low set through GPI_INV register
bit 7.
GPIO[8]
Input
Only
LDRQ[1]#
Resume
Input active status read from GPE1_STS register
bit 8.
Input active high/low set through GPI_INV register
bit 8.
GPIO[9]
Input
Only
AC_SDIN[1]
Resume
Input active status read from GPE1_STS register
bit 9.
Input active high/low set through GPI_INV register
bit 9.
GPIO[10]
N/A
N/A
N/A
Not Implemented
GPIO[11]
Input
Only
SMBALERT#
Resume
Input active status read from GPE1_STS register
bit 11.
Input active high/low set through GPI_INV register
bit 11.