INT 14 - MultiDOS Plus IODRV - WRITE CHARACTER TO PORT
        AH = 06h
        AL = character
Return: AL = status
            00h successful
Notes:  the port number is stored at offset BEh in the Task Control Block
        if output queue is full, the calling task is blocked until the
          character can be stored
SeeAlso: AH=04h"MultiDOS",AH=05h"MultiDOS",AH=21h"MultiDOS"