INT 0fH: IRQ 7 LPT1

  INT 0fH is a hardware-generated interrupt (IRQ 7) forced by LPT1 when it
  is ready to receive a character (but only when the printer controller has
  been programmed to generate the interrupt).

See Also: IRQs: Hardware Interrupts
          Printer Ports
          BIOS Data Area
          ROM-BIOS Functions
          DOS Functions
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