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jdm:pc9801:int18h

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NEC PC-9801 - INT 18h

AH = 00h - Get Keystroke

Input:

  • AH = 00h

Output:

  • AX = keystroke

The keystroke is removed from the input buffer.

AH = 01h - Check Keystroke

Input:

  • AH = 01h

Output:

  • AX = keystroke
  • BH = 1 if keystroke in buffer, else 0.

The keystroke is NOT removed from the input buffer.

AH = 02h - Get Shift Status

Input:

  • AH = 02h

Output:

  • AL = shift flags:
    • bit 0 - SHIFT (pressed)
    • bit 1 - CAPS (held)
    • bit 2 - KANA (held)
    • bit 3 - GRPH (pressed)
    • bit 4 - CTRL (pressed)

AH = 03h - Initialize Keyboard Interface

TODO

AH = 04h - Access Keystroke Bitmap

Input:

  • AH = 04h
  • AL = byte of keystroke bitmap (bits 0-3)

Output

  • AH = keystroke bitmap value

TODO

jdm/pc9801/int18h.1640434108.txt.gz · Last modified: 2021/12/25 12:08 by asie