INT 14 - Digiboard - CCB COMMAND - SET INTERRUPT TO HOST MASK AX = 1646h BL = bits to set BH = bits to clear CL = byte 1 DX = port number (00h-03h) (04h-43h for XAPCM232.SYS) Return: AH = status 00h successful 80h error FFh error SeeAlso: AH=16h"Digiboard",AX=1647h