Int 17 Fn 2409  - Shamrock Software Net.24 V3.11+ - Transmit Command, Wit  [N]

   AX = 2409h
   BX = target address
   CX = number of data bytes
   DL = command code to send
   DS:SI -> data bytes for command

Return: AL = status (see also AX=2400h)
       03h no response
       06h remote currently unable to perform command

See Also: AX=2405h,AX=2408h