Jo22 wrote on 2025-06-02, 08:28:

myne wrote on 2025-06-02, 03:42:

What is the fundamental difference between int13h translation to sata, and an int5h translation from sb# to hda?

Software interrupt vs hardware interrupt, I think.
MS-DOS uses int21h, for example.

Ah, okay. Now I understand the confusion here as well. Indeed, IRQ 5 (hardware interrupt typically used by sound cards) is not the same as INT 5h (software interrupt).

Both the IBM compatible PC BIOS API and the DOS API are accessed through software interrupts. Same with DOS device drivers. And those you can easily intercept by hooking into them, without having to result to virtualization and I/O port trapping and such, which can't be done in "pure" real mode.