TECHNICAL REFERENCE
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MEMORY ADDRESS MAP
Address Range (Hex)
Description
000000H - 09FFFFH
640 KB of Conventional RAM
0A0000H - 0BFFFFH
128 KB of Video RAM
0C0000H - 0EFFFFH
256 KB of I/O Expansion ROM
0F0000H - 0FFFFFH
64 KB of System BIOS ROM
0100000H - 7FFFFFFFH
1 MB ~ 128MB of User RAM
DMA CHANNELS
CHANNEL
Function
DMA 0
Reserved
DMA 1
Reserved
DMA 2
Floppy Disk Controller
DMA 3
ECP Parallel Port
DMA 4
Cascade for DMA #1
DMA 5
Reserved
DMA 6
Reserved
DMA 7
Reserved
INTERUPT CONTROLLER
IRQ
Function
IRQ 0
System timer output
IRQ 1
Keyboard
IRQ 2
Cascade for INTC #2
IRQ 3
Serial port #2
IRQ 4
Serial port #1
IRQ 5
Parallel port #2
IRQ 6
Floppy disk controller
IRQ 7
Parallel port #1
IRQ 8
Real time clock
IRQ 9
Software redirected to INT 0AH (IRQ 2)
IRQ 10
Reserved
IRQ 11
Reserved
IRQ 12
PS/2 Mouse
IRQ 13
Math Coprocessor (CPU Internal)
IRQ 14
Primary Hard disk
IRQ 15
Secondary Hard Disk
NMI
Parity Check Error