Read the statement by Michael Teeuw here.
Problem with PIR Sensor's control
I added pir sensor for my mirror but i dont want to control hdmi output with it. Because when hdmi is turned off, it changes to blue screen. So i want to control raspberry’s sleeping mode with hc-sr501 to on/off. After that i can take black screen. How can i do it?
@Damian yes i did black but its an alert turning: “No signal”. How can i deactive that alert
you cannot It is built in