IBM 100/10 User Manual
143
Appx. D
D.2 1st MB memory map
D.3 DMA channel assignments
Table D.2: 1st MB memory map
Addr. range (Hex)
Device
F0000h - FFFFFh
System ROM
*CC000h - EFFFFh
Unused (reserved for Ethernet ROM)
C0000h - CBFFFh
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
* E0000 - EFFFF is reserved for BIOS POST
Table D.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
* Audio DMA select 1, 3, or 5
** Parallel port DMA select 1 (LPT2) or 3 (LPT1)
** Parallel port DMA select 1 (LPT2) or 3 (LPT1)