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.

Hyperion LED’s & Nagios (Part 2)

Maybe you read Part 1, maybe you skipped it 🙁

Either way Part 2 is going to cover creating a new effect for Nagios. I wont say it’s the best bit of python programming I’ve done (Yes I copied and changed another effect as a starting point). The main thing I wanted was an alert status (yes Star Trek does come into it).

There’s 4 files to this effect:

  1. alert.py – The actual python program
  2. alert-green.json – etting a green colour (yes it’s spelt COLOUR not color!!!!!)
  3. alert-yellow.json
  4. alert-red.json

My hyperion is installed to ‘/opt/hyperion’ so first thing is to go to the effects directory

cd /opt/hyperion/effects

Then create the alert.py file

nano alert.py

Paste the following into it and save the file

import hyperion
import time
import colorsys
import numpy as np

# Get the rotation time
colorfrom =     hyperion.args.get('colorfrom', (0,0,0))
colorto =       hyperion.args.get('colorto', (0,255,0))
speed   =       float(hyperion.args.get('speed', 0.05))
freq    =       float(hyperion.args.get('frequency', 2.5))
step    =       float(hyperion.args.get('step', 30.0))
ledCount =      hyperion.ledCount

# Setup the colors
colorfromnp     =       np.array(colorfrom)
colortonp       =       np.array(colorto)

#define the lerp calc
def lerp(a, b, t):
        x = a*(1 - t) + b*t
        x = np.around(x)
        x = x.tolist()
        return x

# Start the write data loop
while not hyperion.abort():
        for i in range(0,int(step)):
                n = i / step
                thiscolor = lerp(colorfromnp, colortonp, n)
                colorLedsData = ledCount * bytearray((int(thiscolor[0]), int(thiscolor[1]), int(thiscolor[2])))
        for i in range(1,int(step)):
                n = i / step
                thiscolor = lerp(colortonp, colorfromnp, n)
                colorLedsData = ledCount * bytearray((int(thiscolor[0]), int(thiscolor[1]), int(thiscolor[2])))
        colorLedsData = ledCount * bytearray(colorfrom)

I do use a numpy array, I can’t remember installing it but may have done. You can test if you have it installed

import numpy as np

Then we create the alert-green.json

nano alert-green.json

And Paste

        "name" : "Green Alert",
        "script" : "alert.py",
        "args" :
                "colorfrom" : [0,0,0],
                "colorto" : [0,255,0],
                "speed" : 0.05,
                "freq" : 2.5,
                "step" : 30.0


        "name" : "Yellow Alert",
        "script" : "alert.py",
        "args" :
                "colorfrom" : [0,0,0],
                "colorto" : [255,255,0],
                "speed" : 0.05,
                "freq" : 2.5,
                "step" : 30.0


        "name" : "Red Alert",
        "script" : "alert.py",
        "args" :
                "colorfrom" : [0,0,0],
                "colorto" : [255,0,0],
                "speed" : 0.05,
                "freq" : 2.5,
                "step" : 30.0

Finally restart hyperion to pickup the new effects

service hyperion restart

That’s it, you should now be able to run these effects. From the terminal:

hyperion-remote -e "Red Alert"

Should start the led’s glowing Red. If not I’d start with ‘hyperion-remote -l’ to check the effects are listed, then move on to working out what’s missing (see above about numpy array).

A few notes on this effect:

  • Originally I programmed it forced to black, but it made sense to change this to a colorfrom value for future (if you want it green and fading to red for example).
  • The speed is how quickly to progress through the fade.
  • The step is how many colours it goes through to get from the colorfrom to the colorto
  • Working out the speed and the step together are important for a nice fade (not jerky).
  • The Freq in how long it stays on black before running the fade again.

This completes the hyperion side of the setup. I now have this effect installed and running on 3 PI’s and yes when there’s a problem they ALL go to yellow/red alert

See Part 3 for the nagios setup

Hyperion LED’s & Nagios (Part 1)

Part 1 is more Background story on my use of WS2801 WS2812b and Hyperion with the Raspberry Pi. Skip to Part 2 for the techy bit.

I’ve been using Hyperion for a while. I setup light behind the TV first off (using sticky tape) WS2801 and RaspBMC. This work brilliantly and I loved it. Spent hours tweaking the config so the LED’s were picking up the correct colour to the screen.

With all that working and a length of LED’s left over I decided to run some up the stairs. They sit just under the banister lip so you can’t see them, just the light on the stairs. I set these to Rainbow swirl and let it. They’re been running for months, occasionally changing the effect to show off what they can do.

Then disaster struck, the power adapter stopped working. Have to be honest I didn’t really notice until I was going to bed at 2am and almost fell over. They’ve been there giving off light (possibly a bit bright if anything) and I just got used to being able to see in the middle of the night without any other lights.

Anyway I digress, ordering a new power adapter I went searching for more LED’s (yes you can’t have enough of them once you’ve been playing). I decided that I’d really like to run some in my bedroom, the effects are cool and there would be plenty of light I wont need to use the main light with them on.

So I looking at where I originally bought my WS2801’s and nothing 🙁 so off to google, the obvious thing was I was going to have a hard time sourcing them in the UK. but why they’re great. So off I went to the hyperion git site for info and found there’s newer versions WS2811 and WS2812b. ah that may help, another search and I found someone selling a load on ebay. So I bought all he had 3xreels of WS1812b’s.

They turned up and I connected them up to try them as directed by hyperion. It was at this point I read the important bits RPi2 isn’t working yet and there maybe a problem with the PI communicating with them due to the voltage. I really thought I was going to have to make another little circuit to (buffer?) get them working. As a last ditched attempt it was mentioned try removing the resistor and try running them direct from python. I did both at the same time (not the best decision for troubleshooting. But to my surprise they worked.

So I killed the python program and restart hyperion, yep they’re working.

So off I went to stick them to the ceiling (they have sticky tape on the back). Done. If only I’d thought about connecting them before I stuck them up. I now had to work up in the air joining the cables. Not to worry I’ve done worse.

So I go to get what I need, by the time I got back up they’ve come down 🙁 bloody gravity! Now you’d think at this point I’d connect them up and sort out attaching them later Nope! (didn’t even enter my head) I was now on track to get them to stay up. Enter ‘SuperGlue’, applied little dots along the strip and stuck them up (yes I glued my fingers to the ceiling too). Finally they’re up and staying there. Oh I should have connected them when they were down!

‘Bugger it, where’s my screw driver’ I connected them up, put a power connector on the end and powered them and the PI.

Then installed hyperion on yet another pi. and it all worked like magic.

Have a look at the video, there’s no light other than the TV and it’s dark outside, but the room is really bright.


Click here for Part 2