/ledcontrolserver

Server for my LEDs

Primary LanguagePython

ledcontrolserver

Setup

Parts required

  • One strip of RGB LEDs. Any generic one like this one will work.
  • An appropriate power supply if it doesn't come with the strip.
  • Three N-Channel MOSFET transistors. I used IRLZ34N.
  • A Raspberry Pi
  • Optional
    • I used a breadboard and connector cables.
    • A USB wifi dongle.

Setup your raspberry pi

  • Follow this guide.
    • I didn't bother with an SD card pre installed with NOOBS, I just straight up installed Raspian using this guide.
  • If you went with the wifi dongle option, here are the setup instructions.

Make your connections like so:

alt text The part on the top right is the power supply, or an extension (not necessarily a separate circuit-board part)

Software setup

  • Run sudo apt-get update
  • Install ngrok on the Raspberry Pi. Use the Linux 32 bit version.
  • Install PiGPIO.
  • Install screen using sudo apt-get install screen
  • Clone this repo into your home directory which will be something like /home/pi
    • After cloning, you should get a /home/pi/ledcontrolserver directory.
  • Edit /home/pi/ledcontrolserver/led.py. Change the PIN_RED, PIN_GRN and PIN_BLU variables to match whatever GPIO pins you connected your red, green and blue LED connections to (via the transistors of course) respectively.

Running the whole thing

  • Run sudo pigpiod
  • Run screen -S ngrok. In the screen that appears, do the following:
    • Run ./ngrok http 8080 (assuming you put it in your home directory)
    • Note down the Public URL once ngrok establishes the tunnel
    • Press Ctrl+A and then D to detach the screen.
  • Run screen -S server. In the screen that appears , do the following:
    • Run python /home/pi/ledcontrolserver/led.py
    • Press Ctrl+A and then D to detach the screen.
  • You can resume any of your screens using screen -r ngrok or screen -r server
  • You can now control your LED strip by using to the Public URL from the step above. See the API section.

Optional steps

If your Raspberry Pi gets disconnected or rebooted for any reason or your internet router gets rebooted, you'll have to many of the above steps. To avoid that, I have added some automation. This will run ngrok and the server every time the Raspberry Pi boots and send you the new Public URL by email.

  • Move all the files from /home/pi/ledcontrolserver/other_tools/ to the home directory /home/pi/
  • Run sudo crontab -e
    • Add @reboot . /home/pi/onstartup.sh to the end of the file that opens and save.
  • Install mailx.
  • Edit the .mailrc file with your GMail details.
    • If you use 2-factor authentication, use an app password instead.

API

You should have an ngrok Public URL from the above steps that looks something like http://abcd123.ngrok.com. Append one of the following endpoints and send a GET request to the full path to that URL to control the LED strip (eg: Go to http://abcd123.ngrok.com/setstate/255/255/255 in your browser).

Endpoints:

  • /getstate : Get the current state of the LED strip.
  • /setstate/100/128/234 : Set the color of the LED strip.
    • The 3 numbers are the Red, Green, and Blue intensities.
    • They can range between 0 and 255.
    • Use a colorpicker tool for finding out RGB values for colors.
  • /turnoff : Turn the LED strip off.
  • /turnon : Turn the LED strip on.
    • The first time this is run, it will have no effect, because the color is set to black, which is the same as the strip being off. Use /setstate to set some color first before using /turnon and /turnoff
  • /turnonifdark : If the strip is off, this turns the LED strip on, only if sunset has occurred and it is before sunrise the next morning.
    • Edit the file /home/pi/ledcontrolserver/suncycle.py to use your latitude and longitude instead for correct sunset and sunrise times.
  • /flicker : Flickers between colors.
  • /pulse : Starts 1 slow pulse of color.