
D.1 System I/O ports
Table 
| Addr. range (Hex) | Device | 
| DMA controller | |
| 
 | 
 | 
| Interrupt controller 1, master | |
| 
 | 
 | 
| Chipset address | |
| 
 | 
 | 
| 8254 timer | |
| 
 | 
 | 
| 8042 (keyboard controller) | |
| 
 | 
 | 
| 
 | 
 | 
| DMA page register, | |
| 
 | 
 | 
| Interrupt controller 2 | |
| 
 | 
 | 
| DMA controller | |
| 
 | 
 | 
| 0F0 | Clear math  | 
| 
 | 
 | 
| 0F1 | Reset math  | 
| 
 | 
 | 
| Math  | |
| 
 | 
 | 
| Fixed disk | |
| 
 | 
 | 
| Reserved (Game I/O) | |
| 
 | 
 | 
| Reserved | |
| 
 | 
 | 
| Serial port 4 | |
| 
 | 
 | 
| Serial port 2 | |
| 
 | 
 | 
| Prototype card | |
| 
 | 
 | 
| Reserved | |
| 
 | 
 | 
| Parallel printer port 1 (LPT 2) | |
| 
 | 
 | 
| SDLC, bisynchronous 2 | |
| 
 | 
 | 
| Bisynchronous 1 | |
| 
 | 
 | 
| Monochrome display and printer adapter(LPT1) | |
| 
 | 
 | 
| Reserved | |
| 
 | 
 | 
| Color/graphics monitor adapter | |
| 
 | 
 | 
| Serial port 3 | |
| 
 | 
 | 
| Diskette controller | |
| 
 | 
 | 
| Serial port 1 | |
| 
 | 
 | 
| 443 | Watchdog timer | 
| 
 | 
 | 
* 
106 
