Int 33 Fn 000C  - MS Mouse V1.0+ - Define Interrupt Subroutine Parameters  [M]

   AX = 000Ch
   CX = call mask (see below)
   ES:DX -> FAR routine

Notes: when the subroutine is called, it is passed the following values:
     AX = condition mask (same bit assignments as call mask)
     BX = button state
     CX = cursor column
     DX = cursor row
     SI = horizontal mickey count
     DI = vertical mickey count
   in text modes, the row and column will be reported as a multiple of
     the cell size, typically 8x8 pixels
BUG:   some versions of the Microsoft documentation incorrectly state that CX
     bit 0 means call if mouse cursor moves, and swap the meanings of SI
     and DI

See Also: AX=0018h

Bitfields for call mask:
 bit 0 call if mouse moves
 bit 1 call if left button pressed
 bit 2 call if left button released
 bit 3 call if right button pressed
 bit 4 call if right button released
 bit 5 call if middle button pressed (Mouse Systems/Logitech mouse)
 bit 6 call if middle button released (Mouse Sys/Logitech mouse)
 bits 7-15 unused