| PCI Base | PCI | 
 | |
| Class | 
 | ||
| Description | |||
| (lower | |||
| S3  | 
 | ||
| nibble) S2 | 
 | ||
| 
 | 
 | ||
| 
 | 
 | 
 | |
| 
 | Bridge devices | 
 | |
| 
 | 
 | 
 | |
| 
 | 00 | Host bridge | |
| 
 | 
 | 
 | |
| 
 | 01 | ISA bridge | |
| 
 | 
 | 
 | |
| 
 | 02 | EISA bridge | |
| 
 | 
 | 
 | |
| 6 | 03 | MCA bridge | |
| 
 | 
 | ||
| 04 | |||
| 
 | |||
| 
 | 
 | 
 | |
| 
 | 05 | PCMCIA bridge | |
| 
 | 
 | 
 | |
| 
 | 06 | NuBus bridge | |
| 
 | 
 | 
 | |
| 
 | 07 | Cardbus bridge | |
| 
 | 
 | 
 | |
| 
 | 80 | Other bridge device | |
| 
 | 
 | 
 | |
| 
 | Simple communication controllers | ||
| 
 | 
 | 
 | |
| 7 | 00 | Serial controllers | |
| 
 | 
 | ||
| 01 | Parallel port | ||
| 
 | |||
| 
 | 
 | 
 | |
| 
 | 80 | Other communication controllers | |
| 
 | 
 | 
 | |
| 
 | Generic system peripherals | ||
| 
 | 
 | 
 | |
| 
 | 00 | PIC | |
| 
 | 
 | 
 | |
| 8 | 01 | DMA controller | |
| 
 | 
 | ||
| 02 | System timer | ||
| 
 | |||
| 
 | 
 | 
 | |
| 
 | 03 | ||
| 
 | 
 | 
 | |
| 
 | 80 | Other system peripherals | |
| 
 | 
 | 
 | |
| 
 | Input devices | 
 | |
| 
 | 
 | 
 | |
| 
 | 00 | Keyboard controller | |
| 
 | 
 | 
 | |
| 9 | 01 | Digitizer (pen) | |
| 
 | 
 | 
 | |
| 
 | 02 | Mouse controller | |
| 
 | 
 | 
 | |
| 
 | 80 | Other input controllers | |
| 
 | 
 | 
 | |
| 
 | Docking stations | 
 | |
| 
 | 
 | 
 | |
| A | 00 | Generic docking station | |
| 
 | 
 | 
 | |
| 
 | 80 | Other type of docking station | |
| 
 | 
 | 
 | |
| Appendix A. Interpreting Firmware Error Codes | 
