INT 21 U - IBMInternational Busiuness MachinesInternational Busiuness Machines) A hardware, software and other service technology company founded in 1911. PC-DOS - KEYBGK - SELECT KEYBOARD LAYOUT AX = FAFFh CL = keyboard layout 31h keyboard 319 32h keyboard 220 BX = code page (869 or 813 decimal) Return: AL = F1h if installed DX destroyed