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Program the 8259 PIC for Interrupt Management

hard2/8

Implement Simple Interrupt Handler for Timer or Keyboard Program the PIT for Precise Timing

Language

Compiler

2.0s Limit 256MB

Submit and pass all tests to enable saving to GitHub.

Implementation

Implement PIC initialization and control in C.

Requirements:

Implement pic_remap() with all 4 ICWs for both PICs
Show correct ICW values
Implement pic_send_eoi() for master, slave, and cascaded
Implement pic_enable_irq() and pic_disable_irq()
Show IRQ-to-vector mapping
Demonstrate masking and unmasking
Print initialization sequence
Show IMR read/modify/write operations
Handle slave IRQs correctly (EOI to both)

Test:

Show ICW1 sent
Show remapping to vectors 32-47
Show EOI sent
Show IRQ enabled/disabled

Why This Matters

Every x86 hobby kernel on the OSDev wiki remaps the PIC to vectors 32-47 with these exact four ICWs, because leaving IRQ0-7 at their BIOS default of vectors 8-15 collides head-on with CPU exception vectors like the double-fault (8) and general-protection-fault (13) handlers. Linux's own arch/x86/kernel/i8259.c performs this identical remap during early boot before switching most systems over to the APIC.

Hints

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Validation Suite

main.c

Workspace 1.0

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