Hyperion with Sunrise and Sunset

You may have gotten here from my hyperion with nagios writeup, this doesn’t follow on from that and is separate, but maybe of interest.

The basic idea: I’ve now got LED’s in my room and would like them to come on before I go to bed so I can see without falling over. The ones on the stair I just leave running, but like hell am I going to sleep with such a bright LED (I probably could, I can sleep in the day but I thought it would be a better idea for them to come on ready).

I could have just set this up on a basic cron and picked a time early enough to account for summer/winter before I go to bed. but where’s the fun in that. I know my PI can work out when the sunrise/sunset is. so it can’t be that difficult to set something up.

After a little bit of searching I come across sunwait you will need this or a similar program. I wont cover installing sunwait on the PI here. just the config I use with hyperion.

First I need a script that sunwait will call and tell it what it needs to do. Here’s my sun-light.sh

case "$1" in
        /usr/bin/hyperion-remote -p 50 -e "Knight rider"
        /usr/bin/hyperion-remote -p 50 -e "Little Chaser Blue"
        echo "Usage: $0 {sunrise|sunset}"
        exit 1
exit 0

Don’t forget to make this script executable ‘chmod +x sun-lights.sh’

This is basically told to either run sunset or sunrise and will then call hyperion-remote passing the relevant priority and effect. (Little Chaser Blue is a copy and customisation of Knight Rider)

Then I added the following to /etc/crontab

0 02   * * *   root    sunwait -p sun up 51.xxxxN 3.xxxxW ; /root/sun-lights.sh sunrise
12 02   * * *   root    sunwait -p sun down 51.xxxxN 3.xxxxW ; /root/sun-lights.sh sunset

This basically run’s sunwait which will wait until the sun is either coming up or going down at the specified co-ordinates before running the bit after ;

The important bit to get your head around if you must have cron run this at a time well before the sun will rise or set. midnight and midday seems like a good safe bet.

I know I’ve skipped over the actual installation of sunwait and more details on hyperion and running the scripts to check it works, but it’s 1am and I just want to save this 🙂 So if you’ve got this far and are still confused, comment below and I’ll expand on the relevant bits.