System I/O address specifications
I/O address (hex) | System function (shipping configuration) | |
|
|
|
000 | - 00F | DMA controller no. 1 |
|
|
|
010 | - 01F | Unused |
|
|
|
020 | - 021 | Interrupt controller no. 1 |
|
|
|
022 | - 024 | Opti chipset configuration registers |
|
|
|
025 | - 03F | Unused |
|
| |
02E - 02F | 87334 “Super I/O” configuration for CPU | |
|
|
|
040 | - 05F | Counter/timer registers |
|
|
|
044 | - 05F | Unused |
|
|
|
060 |
| Keyboard controller |
|
|
|
061 |
| Port B |
|
|
|
062 | - 063 | Unused |
|
|
|
064 |
| Keyboard controller |
|
|
|
065 | - 06F | Unused |
|
|
|
070 | - 071 | NMI enable/RTC |
|
|
|
072 | - 07F | Unused |
|
|
|
080 | - 08F | DMA page registers |
|
|
|
090 | - 091 | Unused |
|
|
|
092 |
| Port A |
|
|
|
093 | - 09F | Unused |
|
| |
0A0 - 0A1 | Interrupt controller no. 2 | |
|
| |
I/O Address (hex) | System function (shipping configuration) | |
|
| |
0A2 - 0BF | Unused | |
|
| |
0C0 - 0DF | DMA controller no. 2 | |
|
| |
0E0 - 0EF | Unused | |
|
| |
0F0 - 0F1 | Coprocessor busy clear/reset | |
|
| |
0F2 - 0FF | Unused | |
|
|
|
100 | - 16F | Unused |
|
|
|
170 | - 177 | Secondary fixed disk controller |
|
|
|
178 | - 1EF | Unused |
|
| |
1F0 - 1F7 | Primary fixed disk controller | |
|
| |
1F8 - 200 | Unused | |
|
|
|
201 |
| JoyStick (decoded in ESS1688) |
|
|
|
202 | - 21F | Unused |
|
|
|
72 Chapter 6 Specifications
