Int 21 Fn FFE3  - Topware Network OS V5.10+ - Send Packet                  [N]

   AX = FFE3h
   DL = 02h
   CX = length of data buffer
   DS:SI -> buffer containing data

Return: CF clear if successful
   CF set on error
       DH = error code (0Ch,11h) (see AX=FFE3h/DL=00h)