Int 16 Fn 02  - Keyboard - Get Shift Flags                                 [B]

   AH = 02h

Return: AL = shift flags (see below)

See Also: AH=12h,AH=22h,INT 17/AH=0Dh,INT 18/AH=02h

Bitfields for shift flags:
 bit 7 Insert active
 bit 6 CapsLock active
 bit 5 NumLock active
 bit 4 ScrollLock active
 bit 3 Alt key pressed (either Alt on 101/102-key keyboards)
 bit 2 Ctrl key pressed (either Ctrl on 101/102-key keyboards)
 bit 1 left shift key pressed
 bit 0 right shift key pressed