Gateway 980 - Manual (Page 109)

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Appendix A:
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Electronic specifications
Memory map
Interrupts
The following table reflects a typical configuration, but you can change these
interrupts. Use this information to determine how to program each interrupt.
The actual interrupt map is defined using configuration registers in the I/O
controller. I/O Redirection Registers in the I/O APIC are provided for each
interrupt signal. The signals define hardware interrupt signal characteristics for
APIC messages sent to local APIC(s).
Address Range (hex) Amount Function
0 to 07FFFFh 640 KB DOS region, base system memory
0A0000h to 0BFFFFh 128 KB Video or SMM memory
0C0000h and 0DFFFFh 128 KB Expansion card BIOS and buffer area
0E0000h to 0FFFFFh 128 KB System BIOS
0E0000h to 0EFFFFh 2 MB Extended system BIOS
FC000000h to FFFFFFFFh 64 MB PCI memory space
Important If you disable an IDE controller to free the interrupt for that
controller, you must physically unplug the IDE cable from
the system board. Simply disabling the drive by configuring
the SSU option does not make the interrupt available.
Interrupt (IRQ) Description
0 8254 timer
1 Keyboard controller
2 Cascade
3 Serial port
4 Serial port