--> Serial communication

Arduino -> RPi
button_pressed\n

RPi -> Arduino
open_door\n
close_door\n
print_text:this is some text\n
play_buzzer:frequency,duration\n  --> play_buzzer:200,1000\n
set_led:red,green,blue\n          --> set_led:003,255,050\n

--> Telegram communication

/start
/open
/deny
