Appendix
PEB-7431VL User’s Manual
Appendix A
I/O Port Address Map
Each Peripheral device in the system is assigned a set of I/O port addresses, which
also becomes the identity of the device. The following table lists the I/O port
address used.
Memory Area
Size
Device Description
0000 – 003F
1K
Interrupt Area
0040 – 004F
0.3K
BIOS Data Area
0050 – 006F
0.5K
System Data
0070 – 04C6
17K
DOS
04C7 – 0582
2.9K
Program Area
0583 – 9FFE
617K
[Available]
9FFF – 9FFF
0.1K
Unused
= Conventional memory ends at 640K =
A000 – AFFF
64K
VGA Graphics
B000 – B7FF
32K
Unused
B800 – BFFF
32K
VGA Text
C000 – C7FF
32K
Video ROM
C800 – C949
5.2K
Unused
C94A – DFFF
90K
High RAM
E000 – EFFF
64K
Page Frame
F000 – FFFF
64K
System ROM
HMA
64K
First 64K Extended