| Komponente | I/O-Adresse (XT) | I/O-Adresse (AT) |
|---|---|---|
| DMA-Controller 8237 | 000-00F | 000-01F |
| Interrupt-Controller 8259 | 020-021 | 020-03F |
| Timer 8253/8254 | 040-043 | 040-05F |
| Parallel-Interface | 060-063 | - |
| Tastatur-Interface | - | 060-06F |
| Echtzeituhr | optional | 070-07F |
| DMA-Seiten-Register | 080-083 | 080-09F |
| NMI-Maskierung (Bit 4) | 0A0 | - |
| 2. Interrupt-Controller 8259 | - | 0A0-0BF |
| 2. DMA-Controller 8237 | - | 0C0-0DF |
| Coprozessor | - | 0F8-0FF |
| reserviert | 0A1-0FF | - |
| nicht verwendbar | 100-1FF | - |
| reserviert | - | 100-1FF |
| Joystick | 200-20F | 200-207 |
| PC-Expansion-Unit | 210-217 | - |
| reserviert | 220-24F | - |
| reserviert | 278-27F | - |
| 2. paralleler Port (LPT2) | - | 278-27F |
| reserviert | 2F0-2F7 | - |
| 4. serieller Port (COM4) | - | 2E8-2EF |
| 2. serieller Port (COM2) | 2F8-2FF | 2F8-2FF |
| HDD-Controller | 320-32F | 1F0-1F7 |
| 1. paralleler Port (LPT1) | 378-37F | 378-37F |
| reserviert | 3A0-3AF | - |
| Monochrom-/Hercules VGA | 3B0-3BF | 3B0-3BF |
| reserviert | 3C0-3CF | - |
| CGA | 3D0-3DF | 3D0-3DF |
| reserviert | 3E0-3E7 | - |
| 3. serieller Port (COM3) | - | 3E8-3EF |
| FDD-Controller | 3F0-3F7 | 3F0-3F7 |
| 1. serieller Port (COM1) | 3F8-3FF | 3F8-3FF |