Hi,
Alexey Vatchenko schrieb:
> Why not to make it available for the public?
I am/was not even sure that this is the right list. So before I get
flamed for posting at the wrong list I wanted to be sure and not add any
attachments to make it even worse.
- Michael
The screen brightness control in accordance with the battery power
by BIOS can be cancelled by executing the following function.
Application existence setting of power save utility:
AH = 44h
AL = FFh
BX = 0025h
CX = 0002h (power save utility)
DX = 0001h
INT 15h
With this change, the following BIOS functions will be restricted.
* ClockRun(GatedClock)will be disabled.
* System Auto Off will be disabled.
* HDD Auto Off will be disabled.
* Display Auto Off will be disabled.
* Throttle Control by the amount of battery change will be disabled.
* Cooling Method will not be switchable.
* C3 Control will be disabled.
i.e. every power-saving control in BIOS will be prohibited.a
This might cause some problems in the state of power-saving
but this will not cause any problem in PC operation.
2-2.35 Reading brightness level
[2.35]
2-2.35-1 Function
Reads the brightness level.
2-2.35-2 I/O register specifications
(1) Input registers
AH = 44h
AL = FEh
BX = 002Ah brightness level
(2) Output registers
When the function ends normally
AH = 00h
CX = brightness level
DX = possible bit
CF = 0
When an error is encountered
AH = 80h Subfunction error, or function not supported by the system.
CF = 1
2-2.35-3 Function details
This function reads the level of the LCD brightness from SM-RAM.
For example, if a system uses 3 bits to control its brightness (000:Level 0
111:level 7) and the current setting is the Level 3, this function returns
6000h to CX register and E000h to DX register (indicates bit15-13 are valid).
2-2.36 Setting brightness level
[2.35]
2-2.36-1 Function
Sets the brightness level.
2-2.36-2 I/O register specifications
(1) Input registers
AH = 44h
AL = FFh
BX = 002Ah brightness level
CX = brightness level
(2) Output registers
When the function ends normally
AH = 00h
CF = 0
When an error is encountered
AH = 80h Subfunction error, or function not supported by the system.
CF = 1
2-2.36-3 Function details
This function sets the LCD brightness.
The level of the brightness is set to CX register. If a system uses 3 bits to
control the brightness, the valid bits of
CX are bit 15,14,13 and the other bits of CX are not cared (so i<X=E000h and
i<X=FFFFh are same settings).
If a system supports SCI function to set LCD brightness (0115h:LCD Brightness),
the LCD brightness is controlled by the SCI function until this HCI function is
called.
