System Device Numbers
Programmer's Reference Manuals
» System Device Numbers
Note: The following table is only valid for IOMD-based pre-HAL machines. For machines with a HAL (even a HAL running on IOMD), programmers should make no assumption about device numbers following any fixed scheme. Instead, the appropriate OS calls or hardware-specific documentation should be used to determine the correct device numbers.
| # | Meaning |
|---|---|
| 0 | Printer interrupt from 82C710/1 |
| 1 | Unused (was Low battery warning on IOC) |
| 2 | Floppy disc indexer |
| 3 | VSync Pulse |
| 4 | Power on reset |
| 5 | Timer 0 |
| 6 | Timer 1 |
| 7 | FIQ downgrade – reserved for the current owner of FIQ |
| 8 | Expansion card FIQ downgrade; this should normally be masked off |
| 9 | IDE hard disc interrupt (was Sound system buffer change on IOC) |
| 10 | Serial port interrupt from 82C710/1 also mapped to FIQ device 4 |
| 11 | Network interrupt |
| 12 | Floppy disc interrupt |
| 13 | Expansion card interrupt |
| 14 | Keyboard serial transmit register empty |
| 15 | Keyboard serial receive register full |
| 16 | DMA channel 0 |
| 17 | DMA channel 1 |
| 18 | DMA channel 2 |
| 19 | DMA channel 3 |
| 20 | DMA sound channel 0 |
| 21 | DMA sound channel 1 |
| 22 | ARM 7500 mouse port receive register full |
| 23 | ARM 7500 mouse port transmit register empty |
| 24 | ARM 7500 joystick A-to-D completion |
| 25 | ARM 7500 event 1 |
| 26 | ARM 7500 event 2 |
Controlling sources: Hdr:DevNos managed by the allocations manager
Notes
PCI device numbers are allocated dynamically – see PCI_ReadInfo (bit 11).
See also
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