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85 Appx. C
C.2 1st MB memory map
C.3 DMA channel assignments
CF8-CFB PCI Configuration Address
CFC-CFF PCI Configuration Data
D00-FFFF -available for system use-
Table C.2: 1st MB memory map
Addr. range (Hex) Device
F0000h - FFFFFh System ROM
*D0000h - EFFFFh Unused (reserved for Ethernet ROM)
C0000h - CFFFFh Expansion ROM (for VGA BIOS)
B8000h - BFFFFh CGA/EGA/VGA text
B0000h - B7FFFh Unused
A0000h - AFFFFh EGA/VGA graphics
00000h - 9FFFFh Base memory
*
If Ethernet boot ROM is disabled (Ethernet ROM occupies about 16 KB)
* E0000 - EFFFF is reserved for BIOS POST
Table C.3: DMA channel assignments
Channel Function
0 Available
1 Available (audio)
2 Floppy disk (8-bit transfer)
3 Available (parallel port)
4 Cascade for DMA controller 1
5 Available
6 Available
7 Available
* Parallel port ECP mode DMA select 1 or 3
Table C.1: System I/O ports
Addr. range (Hex) Device