HP kp721av Manuale Utente

The ICH10 provides various functions through the use of programmable general purpose 
input/output (GPIO) ports. These systems use GPIO ports and associate registers of the ICH10 
for the following functions:

■

PCI interupt request control

■

Chassis and board ID 

■

Hood (cover) sensor and lock detect

■

Media card reader detect

■

S4 state indicator

■

USB port over-current detect

■

Flash security override

■

Serial port detect

■

REQn#/GNTn# sigal control

■

Password enable

■

Boot block enable

In addition to the serial and parallel port functions, the SIO controller provides the following 
specialized functions through GPIO ports:

■

Power/Hard drive LED control for indicating system events (refer to Table 4-8)

■

Hood lock/unlock controls the lock bar mechanism

■

Thermal shutdown control turns off the CPU when temperature reaches certain level

■

Processor present/speed detection detects if the processor has been removed. The occurrence 
of this event will, during the next boot sequence, initiate the speed selection routine for the 
processor. 

■

Legacy/ACPI power button mode control uses the pulse signal from the system's power 
button and produces the PS On signal according to the mode (legacy or ACPI) selected. 
Refer to chapter 7 for more information regarding power management.