AH = 47h: Contrast95 (HP 95LX Compatibility)

This service provides the functional equivalent of Fcn 62h for programs written specifically for the HP 95LX. The HP 100LX has greater display contrast resolution than the HP 95LX. This service attempts to "hide" these hardware differences by converting the inputs and outputs to what one would expect if the code were running on an HP 95LX.

• Input: AH = 47h
  AL = Subfunction
  = 0 - Set Contrast value in BL.
  = 1 - Read Contrast value and return it in AL.
  AL = 00h-0Fh: HP95 Contrast value (If AL=0)
  > 0Fh: HP95 Contrast value set to 0Fh

• Output: AL = contrast value if AL was 1 at entry
• Registers modified AX