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Use BIOS INT 0x16 for Keyboard Input

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Use BIOS INT 0x13 for Disk Operations Master 16-Bit Stack Operations in Real Mode

Language

Compiler

2.0s Limit 256MB

Submit and pass all tests to enable saving to GitHub.

Implementation

Implement BIOS keyboard services in C with simulation.

Requirements:

Implement read_key() that returns ASCII and scan code
Implement check_key() non-blocking version
Implement get_shift_flags()
Show scan code translation table for common keys
Implement a simple menu system
Show echo of typed characters
Handle special keys (arrows, escape, enter)
Implement a simple line editor (type and backspace)
Print shift state when keys are pressed

Test:

Show key read
Show scan code and ASCII
Show menu selection
Show shift flags
Show line editor working

Why This Matters

GRUB's legacy boot menu and countless DOS-era utilities use exactly this INT 0x16 polling interface to read a keypress before a real interrupt-driven keyboard driver exists, and the fact that BIOS does NOT echo characters (unlike DOS's INT 0x21) is a real gotcha every bootloader author has to handle manually. Special keys like arrows returning ASCII=0 with only a scan code in AH is why line editors must always check AH, not just AL.

Hints

0 / 3 revealed

Validation Suite

main.c

Workspace 1.0

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