STANDARD IRQ ASSIGNMENTS
INTERRUPT REQUEST

IRQ

FUNCTION

BUS SLOT REQUIRED

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^{SYSTEM TIME IC}

^{KEYBOARD CONTROLLER}

^{SECOND IRQ CONTROLLER IC}

 ^{SERIAL PORT 2 (COM2)}

^{SERIAL PORT 1 (COM1)}

^{PARALLEL PORT 2 (LPT2)}

^{FLOPPY DISK CONTROLLER BOARD}

^{PARALLEL PORT 1 (LPT1)}

^{REAL TIME CLOCK (RTC)}

^{UNUSED (REDIRECTED TO IRQ 2)}

^UNUSED

^UNUSED

^{MOTHERBOARD MOUSE PORT}

^{MATH COPROCESSOR}

^{HARD DISK CONTROLLER BOARD}

UNUSED

 

^{NO (MOTHERBOARD)}

^{NO (MOTHERBOARD)}

^{NO (MOTHERBOARD)}

^{YES (8-BIT)}

^{YES (8-BIT)}

^{YES (8-BIT)}

^{YES (8-BIT)}

^{YES (8-BIT)}

^{NO (MOTHERBOARD)}

^{YES (8-BIT)}

^{YES (16-BIT)}

^{YES (16-BIT)}

^{YES (16-BIT)}

^{NO (MOTHERBOARD)}

^{YES (16-BIT)}

^{YES (16-BIT)}