Advanced Configuration and Power Interface Specification

ACPI Software Programming Model
Global System Interrupt Vector
(ie ACPI PnP IRQ# )
8259 ISA IRQs
Master
8259
Slave
8259
0
7
8
15
IRQ0
.
IRQ3
.
IRQ7
IR8
.
IRQ11
.
IRQ15
Figure 5-26 8259–Global System Interrupts
The other interrupt model is the standard AT style mentioned above which uses ISA IRQs attached
to a master slave pair of 8259 PICs. The system vectors correspond to the ISA IRQs. The ISA IRQs
and their mappings to the 8259 pair are part of the AT standard and are well defined. This mapping
is depicted in Figure 5-26.
5.2.14 Smart Battery Table (SBST)
If the platform supports batteries as defined by the Smart Battery Specification 1.0 or 1.1, then an
Smart Battery Table (SBST) is present. This table indicates the energy level trip points that the
platform requires for placing the system into the specified sleeping state and the suggested energy
levels for warning the user to transition the platform into a sleeping state. Notice that while Smart
Batteries can report either in current (mA/mAh) or in energy (mW/mWh), OSPM must set them to
operate in energy (mW/mWh) mode so that the energy levels specified in the SBST can be used.
OSPM uses these tables with the capabilities of the batteries to determine the different trip points.
For more precise definitions of these levels, see Section 3.9.3, “Battery Gas Gauge.”
Table 5-68 Smart Battery Description Table (SBST) Format
Field
Byte
Length
Byte
Offset
Description
Header
Signature 4 0 ‘SBST’ Signature for the Smart Battery Description Table.
Length 4 4 Length, in bytes, of the entire SBST
Revision 1 8 1
Checksum 1 9 Entire table must sum to zero.
OEMID 6 10 OEM ID
Version 6.0 155