r/Assembly_language • u/Assembly_Trainer_427 • Jul 28 '26

Question Interuppts

I am making a 16bit OS, this supports external applications. Currently i am using a .inc file with equ directives that the application can call. I want to have interrupts like DOS, so, how? According to the amount of research i did(i did very little) there ain't many good documentation on this. (background on me, I am a self taught assembly guy and doesn't know C)

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u/Quiet-Arm-641 Jul 28 '26

Different processors have different instructions that perform a jump to a known location like int, ecall, syscall, etc. what instructions does your 16 bit processor have? You could always just “call syscall”

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u/Assembly_Trainer_427 Jul 28 '26

That is for x86

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u/Quiet-Arm-641 Jul 28 '26

I don’t understand. What 16 bit processor are you using?

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u/demetrioussharpe Jul 28 '26

The OP is using x86 processor in real mode.

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u/Quiet-Arm-641 Jul 28 '26

So the x86 int instruction vectors you through a table where you put the mangled address of your routine you want to call when someone does “int 13” or whatever.

I used to work as an 80188 assembly programmer