Are you sure that your Samsung doesn't have an IR receiver? I got a 4K Samsung TV last month. Its remote is bluetooth, but it still has an IR receiver. I used the Samsung IR codes that I got elsewhere from this forum, and the IR codes work fine. I looked into using the RS232 interface, but I could not find where to get Samsung's USB to RS232 cable. Online requests and phone calls led nowhere. Also, their RS232 API doesn't provide 2-way feedback (like querying its status), so there really was no advantage of using RS232 instead of just IR. I couldn't find a way to control it via IP.