automatically lower projection screen when projector is switched on

when space is closed, switch off projector and raise screen

scripts/beamerdetect.sh

@@ -1,4 +1,11 @@
 #!/bin/bash
+if [ "$1" = "off" ]
+then
+  projip=$(arp -an|awk -F'[()]' '/00:50:41:79:d1:34/{print $2}')
+  ssh pi@doorbuzz 'doorbuzz/projectionscreen.sh up'
+  wget -qO - 'http://'"$projip"'/tgi/return.tgi?command=2a3102fd0660'
+  exit
+fi
 prevstatus="unknown"
 while true
 do
@@ -6,12 +13,13 @@ do
   # from the acer webpage we read that bytes 30-31 contain 00 if poer off and 01 if power on
   # we only test if 01, because if off, it can also give no response
   # but seems to be bytes 32-33 more accurate
-  statusbyte="$(wget -qO - 'http://10.2.113.104/tgi/return.tgi?query=info'|awk -F'[<>]' '/<info>/{print substr($3,31,2)}')"  
+  statusbyte="$(wget -qO - 'http://'"$projip"'/tgi/return.tgi?query=info'|awk -F'[<>]' '/<info>/{print substr($3,31,2)}')"  
   if [ "$statusbyte" = "01" ]
   then
     if [ "$prevstatus" != "on" ]
     then
       logger -t $(basename $0) "$$ Projector is on"
+      ssh pi@doorbuzz 'doorbuzz/projectionscreen.sh down'
       prevstatus="on"
     fi
   else

scripts/lockbutton.sh.d/projector.sh

@@ -0,0 +1,2 @@
+#!/bin/bash
+$(dirname $0)/../beamerdetect.sh off