
Chapter 3 | Hardware |
Interrupt Channel Assignments
The channel interrupt assignments are listed in Table
Table
| Device vs IRQ No. | 0 | 1 |
| 2 | 3 | 4 | 5 |
| 6 | 7 |
| 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | ||
| Timer |
| X |
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| Keyboard |
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| X |
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| Secondary |
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| X |
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| Cascade |
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| COM1 |
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| O | D |
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| COM2 |
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| D | O |
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| COM3 |
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| O | O |
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| O | D |
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| COM4 |
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| O | O |
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| D | O |
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| Floppy |
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| X |
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| Parallel |
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| O |
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| D |
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| RTC |
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| X |
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| IDE Primary |
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| X | O | |
| IDE Secondary |
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| O | X | |
| Math Coprocessor |
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| X |
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| PS/2 Mouse |
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| X |
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| PCI INTA |
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| Automatically Assigned |
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| PCI INTB |
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| Automatically Assigned |
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| PCI INTC |
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| Automatically Assigned |
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| PCI INTD |
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| Automatically Assigned |
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| Sound Blaster |
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| D |
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| O |
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| O | O |
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| USB |
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| Automatically Assigned |
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| VGA |
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| Automatically Assigned |
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| Ethernet |
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| Automatically Assigned |
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| Legend: D = Default, O = Optional, X = Fixed |
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| NOTE | The IRQs for the Ethernet, Video, and Internal Local Bus (ISA) are |
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| automatically assigned by the BIOS Plug and Play logic. Local IRQs |
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| assigned during initialization can not be used by external devices. |
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Memory Map
The following table provides the common PC/AT memory allocations. Memory below 000500h is used by the BIOS. Refer to Table
ReadyBoard 700 | Reference Manual | 21 |