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Why does BIOS INT 0x19 load the bootloader to "0x7C00"?

As we know, BIOS interrupt (INT) is 0x19, which is looking for a boot signature (0xAA55). Loads and executes our bootloader at 0x7C00, if found.

My question is: why is 0x7C00? What is the reason? How to evaluate it using some methods?

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He may be dead, but I'm going to answer.

At the beginning of any bootloader, when you set the beginning of a segment to 0x7c00 , then the registers also go to that address. Therefore, ideally, if you study some online resources that tell you how to use the int 0x19 , they will help you move to another address.

To fix this, ideally, reset the stack to 0 at the beginning of each transition to a new address.

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