Kontron ETX-DC, User Manual

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ETX-DC®/ Important Technology Information
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7 Important Technology Information
The following technological information is designed to give the reader a better understanding of some of features of
the ETX®-DC. This information can be referenced when reading the System Resources and BIOS Operation sections
that follow. There are also references to additional documentation that will help to develop a better understanding of
the technical information described herein.
7.1 I/O APIC vs 8259 PIC Interrupt mode
The I/O APIC (Advanced Programmable Interrupt Controller) handles interrupts differently then the 8259 PIC. The
following information explains these differences.
7.1.1 Method of interrupts transmission
The I/O APIC transmits interrupts through the system bus and interrupts are handled without the needs for the
processor to run an interrupt acknowledge cycle.
7.1.2 Interrupt priority
The priority of interrupts in the I/O APIC is independent of the interrupt number.
7.1.3 More interrupts
The I/O APIC in the chipset of the ETX®-DC supports a total of 24 interrupts. The APIC is not supported by all operating
systems. The APIC mode must be enabled in the BIOS setup before the OS installation. APIC only works in ACPI mode.
Note: Enable the APIC mode if your OS supports it.
7.2 Thermal Monitor and Catastrophic Thermal Protection
The Thermal Monitor within the Intel® processor helps to control the processor temperature.
7.3 ACPI Suspend Modes and Resume Events
The ETX®-DC, supports the S1 (POS=Power On Suspend) state and S3 state (=Save to Ram). S4 (=Save to Disk) is not
supported by the BIOS (S4_BIOS) but it is supported by the following operating systems:
» WinME
» Win2k
» WinXP
» Vista