BIOS Processor Instructions
| INT | Address | Type | Function Description |
|---|---|---|---|
| 00h | 0000:0000h | Processor | Divide Error |
| 01h | 0000:0004h | Processor | Single Step |
| 02h | 0000:0008h | Processor | Non-maskable interrupt |
| 03h | 0000:000Ch | Processor | Breakpoint instruction |
| 04h | 0000:0010h | Processor | Overflow instruction |
| 05h | 0000:0014h | BIOS Processor | Print screen Bound range exceeded |
| 06h | 0000:0018h | Processor | Invalid opcode |
| 07h | 0000:001Ch | Processor | Coprocessor not available |
| 08h | 0000:0020h | Hardware Processor | IRQ 0 – System timer Interrupt out of range exception Double exception |
| 09h | 0000:0024h | Hardware Processor | IRQ 1 – Keyboard Coprocessor segment overrun |
| 0Ah | 0000:0028h | Hardware Processor | IRQ 2 – General adapter use/Cascade Invalid Task State Selector |
| 0Bh | 0000:002Ch | Hardware Processor | IRQ 3 – Serial port (COM2) Segment not present |
| 0Ch | 0000:0030h | Hardware Processor | IRQ 4 – Serial port (COM1) Stack exception |
| 0Dh | 0000:0034h | Hardware Processor | IRQ 5 – General adapter use Segment overrun exception General protection fault |
| 0Eh | 0000:0038h | Hardware Processor | IRQ 6 – Diskette controller Page fault |
| 0Fh | 0000:003Ch | Hardware | IRQ 7 – Parallel port (LPT1) |
| 10h | 0000:0040h | BIOS Processor | Video services Coprocessor error |
| 11h | 0000:0044h | BIOS Processor | Equipment list service Alignment check |
| 12h | 0000:0048h | BIOS Processor | Memory size service Machine check |
BIOS Instructions
| INT | Address | Type | Function Description |
|---|---|---|---|
| 13h | 0000:004Ch | BIOS | Floppy/Hard disk services |
| 14h | 0000:0050h | BIOS | Serial communications services |
| 15h | 0000:0054h | BIOS | Systems services |
| 16h | 0000:0058h | BIOS | Keyboard services |
| 17h | 0000:005Ch | BIOS | Parallel printer services |
| 18h | 0000:0060h | BIOS | ROM BASIC/Boot failure |
| 19h | 0000:0064h | BIOS | Bootstrap loader |
| 1Ah | 0000:0068h | BIOS | Time-of-Day services |
| 1Bh | 0000:006Ch | BIOS | <CTRL >< Break> |
| 1Ch | 0000:0070h | BIOS | User timer tick service |
BIOS Hardware Instructions
| INT | Address | Type | Function Description |
|---|---|---|---|
| 1Dh | 0000:0074h | BIOS Data | Video control parameter table |
| 1Eh | 0000:0078h | BIOS Data | Floppy disk configuration table |
| 1Fh | 0000:007Ch | BIOS Data | Video graphics table |
| … | … | … | … |
BIOS Software Instructions
| INT | Address | Type | Function Description |
|---|---|---|---|
| … | … | … | … |
| 20h-3Fh | 0000:0080h-0000:00FCh | Software | DOS interrupts |
| … | … | … | … |
| 44h-45h | 0000:0110h-0000:0114h | Software | ? |
| … | … | … | … |
| 47h-49h | 0000:011Ch-0000:0124h | Software | ? |
| … | … | … | … |
| 4Bh-6Fh | 0000:012Ch-0000:01BCh | Software | ? |
| … | … | … | … |
| 78h-FFh | 0000:01E0h-0000:03FCh | Software | ? |