Int 14 Fn 14  - Pc-mos/386 V5.01 $serial.sys V5.04 - Output String         [S]

   AH = 14h
   CX = number of characters in string
   DX = port number
   ES:BX -> string to be sent
   SI = timeout in timer ticks or 0000h for default

Return: AX = number of bytes actually sent
   ZF clear if successful
   ZF set on timeout

See Also: AH=01h,AH=15h"PC-MOS"