User`s manual

75 Chapter B
B.6 Interrupt Assignments
B.7 1st MB Memory Map
Table B.6: Interrupt assignments
Interrupt# Interrupt source
IRQ 0 (ISA) System timer
IRQ 1 (ISA) PC/AT enhanced PS/2 keyboard (101/102-Key)
IRQ 3 (ISA) Communications port (COM2)
IRQ 4 (ISA) Communications port (COM1)
IRQ 8 (ISA) System CMOS / real time clock
IRQ 12 (ISA) Microsoft PS/2 mouse
IRQ 13 (ISA) Numeric data processor
IRQ 14 (ISA) Primary IDE channel
IRQ 15 (ISA) Secondary IDE channel
Table B.7: 1st MB memory map
Address range (Hex) Device
F000h - FFFFh System ROM
CC00h - EFFFh Unused
CA00h - CBFFh Used
C000h - C9FFh Expansion ROM
B800h - BFFFh CGA/EGA/VGA text
B000h - B7FFh Unused
A000h - AFFFh EGA/VGA graphics
0000h - 9FFFh Base memory.