4 Summary of the HP/Phoenix BIOS

Power Saving and Ergonometry

dog timer detects that the BIOS is inactive (and not reloading the timer once every 6 seconds), the computer is turned off without further BIOS acknowledgment.

The following table summarizes the main signals that drive or are driven by the Little Ben chip.

Signal1

Address

Description

SMI_OFF

 

User wants to power off: computer enters RPO shutdown mode

 

 

(computer clock, HDDs all stopped; only RTC, Little Ben and

 

 

network board still active)

 

 

 

SMI_RWU

pin 69, LBen channel 7

Signal from RTC, FAX, control panel, and power key on keyboard.

 

 

Magic Frame from network board: computer wakes up from RPO

 

 

mode.

 

 

 

CoffeeBreak#

pin 66, LBen channel 0

Connected to the lock button (coffee break) on the control panel.

 

 

 

ASL#

pin 65, LBen channel 4

Connected to the Super IO Auto Soft Lock (ASL) timer.

 

 

Reset by an interrupt from the keyboard or mouse.

 

 

 

APM chip-set SMI#

pin 67, LBen channel 2

SMIs from the chip set pass first to Little Ben, then are sent on to

 

 

the processor on the SMI# line

SMI#

 

 

 

 

StopClk#

 

Stops the processor clock

 

 

 

SMI_CONFIG

 

Tells Little Ben that the processor is in SMM

 

 

 

SMI_ACT#

 

 

 

 

 

SMI_TRIG_EN

 

 

 

 

 

SMI channels

index Ah

Used to enable individual SMI channels during the boot process

 

 

 

SMI_EN

index Bh, bit 0

Enable general SMI generation (during the boot process)

 

 

 

SMI status register

index 10h

This register is cleared when the computer is re-booted

 

 

 

SM

index 11h, bit 1

When set, computer mains button is disabled

 

 

 

 

index 11h, bit 2

When set, Flash ROM is write protected; Super IO space is write

 

 

protected (Serial EEPROM access, serial ports configuration,

 

 

parallel port configuration, flexible disk drive configuration)

 

 

 

 

index 11h, bit 4

When set, flexible disk drive is write protected

 

 

 

PWD_EN

pin 21

Not used

 

index Dh, bit 3

 

 

 

 

Super Secure Mode

pin 64 (shared with

Not used

 

FLPWPT#)

 

 

 

 

1.indicates triggered on a rising edge; indicates triggered on a falling edge

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