List displays.
tvservice -l
2 attached device(s), display ID's are :
Display Number 2, type HDMI 0
Display Number 7, type HDMI 1
tvservice -l | grep '^Display' | while read ENTRY; do
echo "$ENTRY" | tr '\n' ' '
tvservice -s -v $(echo "$ENTRY" | awk '{print $3}' | tr -d ',')
done
Display Number 2, type HDMI 0 state 0x2 [TV is off]
Display Number 7, type HDMI 1 state 0x6 [DVI DMT (82) RGB full 16:9], 1920x1080 @ 60.00Hz, progressive
Power specific display off/on. More info.
tvservice -v 7 -o
Powering off HDMI
tvservice -v 7 -p
Powering on HDMI with preferred settings
fbset -depth 8 && fbset -depth 16 # cycle color depth
Send both displays into low power mode. See differences between vcgencmd and tvservice.
vcgencmd display_power 0
vcgencmd display_power 1