Theory of Operation
Developer’s Kit User Manual 25
3.7.10 GPIO
Table 7. ICH GPIOs
GPIOx CRB Signal Notes
GPIO0 PM_BMBUSY# Bus master busy signal
GPIO1 PCI_REQ#5
GPIO2 INT_PIRQE#
GPIO3 INT_PIRQF#
GPIO4 INT_PIRQG#
GPIO5 INT_PIRQH#
GPIO6 No connect
GPIO7 FP_AUD_DETECT
GPIO8 No connect
GPIO9 IDE_PDIAG1
GPIO10 No connect
GPIO11 SMB_ALERT#
GPIO12 LAN_ISOLATE#
GPIO13 PCI_PME#
GPIO14 No connect
GPIO15 BIOS Config
GPIO16 PM_DPRSLPVR R Mobile only signal – used to lower the voltage of VRM
during C4 state.
GPIO17 PCI_GNT#5 Pull down site STUFFED - SPI boot mode
GPIO18 PM_STPPCI_ICH# PCI clock stop used to support PCICLKRUN# protocol –
Mobile only
GPIO19 SATA1_R1
GPIO20 PM_STPCPU_ICH# Mobile only – output to stop CPU clock during c3 state.
GPIO21 SATA0_R0 Pulled up
GPIO22 PCI_REQ#4