Send Command over TCIP/IP to local device

I want to send the following command “!POWERONMAIN” to a specific ip adress xx.xx.xx.xx port: 84
The manual states: Every command starts with ‘!’ character and ends with carriage return (ascii 0x0D, referred to in this document as )
How can I do this in HA? Please advice. Thx.

Which protocol?

Wild guess:

Try like this: How to send TCP message from HA? - #15 by RaA11

The TELNET with a switch worked great for turning the receiver ON/OFF. Is there anyway to send other commands, but not a switch instead a button for selecting inputs for example (!SRC(X)”Name”) or to get values and send values for a volume slider. The commands look like !VOL?, !VOL(X) etc.

Did you look for built-in media player support of your receiver?

If not, you might try to combine Tom’s suggestion with