Int 10 Fn 5F50  - Chips & Technologies Extended Bios - Get Laptop Display  [V]

   AX = 5F50h

Return: DL = display status (see #0117)

Note:  this call can be used on Toshiba laptops since ~1995 instead of
     INT 42/AX=7503h which is no longer supported with the F655xx chips

See Also: INT 42/AX=7503h

Bitfields for display status:
Bit(s) Description (Table 0117)
 7-4   always 0 ???
 3 1: both displays active (bit 1 also set)
 2 1: normal (monochrome display only), 0: inverse or color
 1 1: internal display active, 0: external only
 0 always set ???