| Hex Range |
Usage |
| 000 01F |
DMA controller 1 (8237A-05) |
| 020 03F |
Interrupt controller 1 (8259A) |
| 040 05F |
Timer 8254.2 |
| 060 06F |
Keyboard controller (8042) |
| 070 07F |
RTC, NMI mask |
| 080 09F |
DMA page registers |
| 0A0 0BF |
Interrupt controller 2 (8259A) |
| 0C0 0DF |
DMA controller 2 (8237A-5) |
| 0E0 0EF |
Reserved |
| 0F0 |
Clear math coprocessor busy |
| 0F1 |
Reset math coprocessor |
| 0F8 0FF |
Math coprocessor |
| 1F0 1F7 |
Hard-disk controller (HDC) |
| 200 207 |
Game I/O |
| 238 23F |
Serial port 4 (used for remapping) |
| 278 27F |
Parallel port 2 |
| 2B0 2DF |
Alternate EGA |
| 278 27F |
Parallel port 2 |
| 2B0 2DF |
Alternate EGA |
| 2E1 |
GPIB (adapter 0) |
| 2F8 2FF |
Serial port 2 |
| 338 33F |
Serial port 3 (used for remapping) |
| 378 37F |
Parallel port 1 |
| 3B0 3BF |
Mono display and printer adapter |
| 3C0 3CF |
EGA |
| 3D0 3DF |
CGA |
| 3F8 3FF |
Serial port 1 |
