Int 15 Fn C200  - System - Pointing Device Bios Interface (ps) - Enable/d  [M]

   AX = C200h
   BH = new state
       00h disabled
       01h enabled

Return: CF set on error
   AH = status (see #0446)

Note:  IBM classifies this function as required

See Also: AX=C201h,AX=C207h,AX=C208h

(Table 0446)
Values for pointing device function status:
 00h   successful
 01h   invalid function
 02h   invalid input
 03h   interface error
 04h   need to resend
 05h   no device handler installed