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Intel 8259 PIC

1976

Intel's Programmable Interrupt Controller, managing hardware interrupt lines in the IBM PC and AT.

Reference & documentation

External technical references for programming Intel 8259 PIC and for writing emulators.

ResourceTypeNotes
Intel 8259A Programmable Interrupt Controller Datasheet ↗DatasheetOfficial Intel 8259A datasheet, complete authoritative reference
Intel 8259 (Wikipedia) ↗PinoutPinout, IRQ/INTR/INTA/CAS signals, cascade wiring
8259 PIC - OSDev Wiki ↗ProgrammingInit sequence, IRQ remapping, EOI, spurious interrupts
Intel 8259A Datasheet (command words) ↗ProgrammingICW1-4 and OCW1-3 command word bit definitions
The i8259 PIC - Davmac.org ↗ReferenceRegisters, ICW/OCW, ELCR, spurious IRQ handling
8259A Verilog HDL Implementation ↗SchematicGate-level 8259A Verilog: priority resolver, IRR/ISR/IMR
QEMU i8259.c interrupt controller emulation ↗SourceQEMU's reference 8259 emulation in C
8259A Verilog Testbenches ↗Test suitePer-module testbenches verifying 8259A behavior