Int 14 Fn 0F  - Digiboard Digichannel PC/x* - Read String                  [S]

   AH = 0Fh
   CX = number of characters to read
   ES:BX -> buffer
   DX = port number (00h-03h) (04h-43h for XAPCM232.SYS)

Return: AX = number of characters read
   ZF clear if successful
   ZF set on error (line status or wrong number of characters)

See Also: AH=0Eh"Digiboard"