In the IBM compatible computer, addresses 0 to 1024 decimal are used for storing interrupt vectors. The entries in this table of vectors point to all the code fragments that control MS DOS screen, disk, mouse, keyboard and other services. The simulator vectors sit between addresses 0 and 15 decimal. It is convenient to start a simulator program with a jump command that occupies two bytes. This means that the first free address for an interrupt vector is [02]. This is used by the hardware timer if the interrupt flag is set.
Have another look at the example program. 10swint.asm
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