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LC

Master 16-Bit Stack Operations in Real Mode

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Use BIOS INT 0x16 for Keyboard Input Use x86 String Instructions (MOVSB, STOSB, LODSB)

Language

Compiler

2.0s Limit 256MB

Submit and pass all tests to enable saving to GitHub.

Implementation

Implement a 16-bit stack simulator in C.

Requirements:

Implement a stack array and SP/SS registers
Implement push16(value) and pop16() operations
Implement pushf() and popf() for flags
Simulate CALL near/RET near
Simulate CALL far/RET far
Implement stack frame setup with BP
Show stack contents after each operation
Demonstrate stack overflow detection
Show interrupt frame (FLAGS, CS, IP pushed)
Print stack state after each operation

Test:

Show push/pop operations
Show CALL/RET sequence
Show stack frame
Show interrupt frame
Show stack overflow warning

Why This Matters

The `mov sp, 0x7C00` stack setup you simulate here is the literal second or third instruction in nearly every real x86 boot sector on the OSDev wiki, chosen precisely because it sits just below the loaded boot sector and grows down into unused low memory. Understanding that hardware interrupts auto-push FLAGS/CS/IP onto this same stack is essential background for writing the IRET-based handlers used throughout the rest of this track.

Hints

0 / 3 revealed

Validation Suite

main.c

Workspace 1.0

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