Hi, im a bit of a noob at this.

I have everything i need but im a total noob in the software installation part (i dunno where to put your modified library for example). Can you please write down a simple step by step software setup?

If you don't have time, here is my output at the end of my experiment: 

Traceback (most recent call last):
  File "strangerlights.py", line 14, in <module>
    from neopixel import *
  File "/usr/local/lib/python3.5/dist-packages/neopixel.py", line 33, in <module>
    import digitalio
  File "/usr/local/lib/python3.5/dist-packages/digitalio.py", line 12, in <module>
    from adafruit_blinka.microcontroller.raspi_23.pin import Pin
  File "/usr/local/lib/python3.5/dist-packages/adafruit_blinka/microcontroller/raspi_23/pin.py", line 1, in <module>
    import RPi.GPIO as GPIO
ImportError: No module named 'RPi'

Hi-

Looks like you are using python 3.5, try installing python 2.7 and run again. Let me know how it goes!

Cheers,
Paul

Hi Paul,

I'm the guy who recently commented on your YouTube video.

I'm having trouble getting the NeoPixels demo to work.  I'm pretty sure I have the wiring set up correctly.  You can see it here:

https://imgur.com/a/7QojbjY

I have a single 5V 5A power supply which is powering the lights and Pi (tiny red wire going into the white mini USB plug).  It's putting out 5.33V.  The data connection to the lights is from physical GPIO pin 18 (blue wire) and ground is physical pin 39 (tiny yellow wire).  The voltage drop from the power supply to the lights is a bit over .7V, so the lights are seeing 5.59V.  I soldered most of the connections to make sure that was not a problem.

I modified the neopixel strandtest.py file to set LED_PIN to 18, and I also tried lowering LED_COUNT to 5.

Any ideas?  Thanks for your python code!

I'd like to add that I followed the other instructions too (disabling the sound modules).  I've also tried reducing the brightness.

Would the fact that my lights are RGB explain my problem?

https://www.amazon.com/gp/product/B01AG923GI/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1

HI John-

I'd suggest first try running the strand on a separate power supply.  The specs for that strand say they are 0.3W per LED, which means either 3A per strand if counting each LED as one, or ~45A if counting R/G/B as each LED. The specs are a little confusing, but even if it is 3A, your 5A supply doesn't give a ton of room for running the rpi. 

Also, check that you are using the correct end of the white DATA wire of the strand.  On mine, the connection has to be on the side of the white arrow. It's hard to tell from your picture.

Cheers,

Paul

Hi Paul,

I tried a bunch of things, with no luck (resolder everything and verify continuity with a volt meter, switched ends of the string, control only a few LEDs, and add a 560ohm resistor between GPIO 18 and the data).  A separate power supply does not help either.

When I initially plug things in, some of the LEDs flash once.

I guess the next thing I'm going to try is to get a 74AHCT125 level converter.

Hi John-

Did you try disabling the audio in the kernel? If I recall correctly, I saw a similar one-flash behavior before I disabled the audio in the kernel. The audio causes the 1-wire signal to get heavily distorted, which can cause odd behavior on the pin.

Hi Paul, yeah, I did disable the audio in the kernel and verified that the modules were not running when I rebooted.  In the meantime, I tried several different things:  new 10A 5V power supply (the first one I got died), switched from diode to the level converter specified in the Adafruit instructions, new set of lights in case I damaged the other ones, connect to either end of the new lights and still no luck.  I did a test with my arduino and it worked first time I tried (very bright lights), so I know the lights are fine.  I suspect that there is something wrong with the signal coming from the Pi, but I really don't have a way to investigate this.

I am wondering if there might be another module, in addition to the disabled audio module, which is the culprit.  I am using the latest version of the Pi OS.  Perhaps something changed.

I made progress on the web/database part of my project, so I would really like to use a Pi.  Maybe I should get a Pi 3.

Anyway, thanks for your help.  Maybe you can think of something else to try.

Interesting, it could be your Pi. Have you tried a different PWM pin?

Hi Paul,

After putting this project aside for a few weeks, I went back to it and tried your last suggestion, and low and behold IT WORKS!  I am so pumped.  I wonder if my Pi is somehow damaged from something I did before, but it does not matter now.  Thanks for all your suggestions.  When I get the final project done I hope to upload a youtube video.

Glad it worked out! Definitely share the video!

Paul,

Here's the video, finally!

https://youtu.be/4dghbk0zUQQ

Nice work! Love the extension on the initial setup to include a server

I finally got around to do this project. Thank you. It worked as expected on first try.  

Nice, glad it worked for you!  

Awesome project!
I just finished setting this project up. I connected the lights power terminal directly to a Raspberry Pi Zero W and everything worked perfectly. I'm using only one 5V 2.1 A power supply on the RaspberryPi. 

Thanks! Good to hear about the Pi Zero W, that's probably my next purchase.

Would everything be the same in terms of hardware if I used 100 lights? I’m using a large wall and want the letters to be spaced out quite a bit. Thanks!

Hi-

Sorry for the super late response, I am not getting proper notifications for some reason...

I'd think 100 lights would work just fine. There should be enough memory in the pi to run that many lights, you may need a larger power supply for LEDs though.

Where the heck do you get a 5v 4a power supply?! I've searched high and low and all I have found is one that's sold out at a Microcenter; I found a 5v 3.6a one, but it doesn't work!

The minimum should be 3A (0.3W per light @ 5V * 50 lights = 3A), it's strange your 3.6A one doesn't work. Either way, we have a local up-cycled electronics hobby store in Portland, OR that I go to called Surplus Gizmos. If you aren't in the Portland area, Amazon has a "frequently bought together" suggestion for this 4A power supply:

https://www.amazon.com/Coming-Data-5-5x2-1mm-Connector-Certified/dp/B0194B80NY/ref=pd_rhf_dp_p_img_1?ie=UTF8&psc=1&refRID=V2JYZ7AD2JSGM3TH0HVP

That will probably work.

Do you have any step-by step instructions for the connections, then? I feel like this project is giving me more grief than it should! I've been chipping away at it for days. As I posted to reddit (https://www.reddit.com/r/raspberry_pi/comments/59x3w1/building_a_stranger_things_letterwallthing_for/):

A few weeks ago, I saw a post on here with some vague instructions on how to make a "Letter Wall" a la "Stranger Things," so I purchased these. The reviews said they worked for this type of project so I got them: https://www.amazon.com/gp/product/B01DZV3PNO/ref=oh_aui_detailpage_o00_s01?ie=UTF8&psc=1

I have next to no programming experience and can't really make heads or tails of what most of it means.

Now, I originally approached this project with the impression (from other reddit posts) that a Raspberry Pi (2 was what I was told; 3 was what I got) would be adequate. I've since read and been told that an Arduino would work better/best, and/or that a RasPi would NOT work, despite the successes that others have posted about.

Additionally, even after soldering the positive and negative wires of the Christmas lights to the correct wires from the cannibalized USB cable I've used, the lights don't seem to quite work - even when connected just to power, not the Raspberry Pi - no data connection at all (which may not have worked at all, anyway).

Currently, I have the lights (which are 5v) plugged straight in to a power adapter in a wall socket. The lights will initially blink on (blue) and then right back off; occasionally, a few minutes later, some lights will turn on in various colors. Sometimes more lights will turn on over time. I left it plugged in overnight after two lights came on this last time, and after six or so hours, no more came on.
I'm really hoping to be able to get these working today (or tomorrow) if possible, so that I can set them up as a Halloween decoration (y'know, on Halloween...) and for Christmas in my classroom. While it's still relevant and interesting, I guess.
I'm willing to head out and purchase some additional parts if necessary.

I'm willing to PayPal some money to somebody who can help me out, if it leads to them actually working. I mean, I'll SKYPE with someone if I have to.

It appears that the audio blacklist is working, so that shouldn't be a problem. I also found that apparently the lights need a 5v/4a power supply, so I soldered the positive and negative to a separate USB plug and did what I could. It looks like I only had 5v/1a and 5v/2.4a, but I tried, nonetheless, and while the lights did initially blink again when I plugged them in, they wouldn't stay on. I also tried "splitting" the power to 2 USB plugs and plugging them both in to 2.4a power supplies, but it didn't work (in fact, they didn't even blink when I did this).
Radio Shack nearby had 5v/3.6a power supplies, so I tried that; while the lights flash brighter (and a slightly different shade of blue-green?) when I plug them in using this, they still don't stay on.

So I suppose that another issue is tracking down a 5v/4a power supply. I live outside Dallas, so there's a lot in the area, but I've tried:

 - Best Buy: The people I get on the phone are completely clueless about what I'm looking for, and most of the descriptions of power supplies/adapters/hubs on the website are inadequate.
 - Fry's Electronics: Same as Best Buy.
 - Microcenter: Can only find one adapter on their website, but it's sold out everywhere except (apparently) Anaheim. Eep.

Arduinos work, but I prefer using a Raspberry pi for this project solely based on cost ($5 Pi Zero) and the ability to use Python.  A Raspberry Pi v2 or v3 should work just fine, I believe the PWM pins are the same.

Can you post a photo of your wiring? Note that the lights shouldn't work at all if you don't have the data wire connected to the Pi. Also, I'd opt for the 5V 3.6A power supply to power your lights.  That should be more than enough to power them and you'll be clear of any multi-power supply noise issues.

Wire connections for you should be the following (based on the wiring photo they supply on Amazon:

V+: This goes to the positive wire of your 3.6A power supply
V-: This goes to the ground wire of your 3.6A power supply. You also connect this to any one of the ground pads on your raspberry pi.
DATA: This goes to the GPIO18 pin of your Pi.

You'll obviously need to power you Pi with a USB cable too. 

Here is my wiring:

Mr.  V's Strangerlights wiring https://imgur.com/gallery/dqcmA

I've cannibalized an old USB cable to use for power, and use the red and black wires from that to connect to the 5v+ and 5v-. The other wire, data, is connected straight to the 8th (data) pin inside the RasPi3. (this is the one I haven't attached a connector or solder to, yet) 

The results are still the same as posted before, unfortunately. 

I see the data wire connected, but I don't see a connection between the GND (5-) and one of the Raspberry Pi's GND pads.  Also, how do you have your power connected?  I'd advise against using a USB cable for power if possible, the strand draws ~3A when all lights are on and USB cables are typically manufactured to handle less. You could always calculate what AWG your wire is to be sure.  A quick google search told me 99% of usb cables are 28AWG, which is a max of 1.4A (too small for this installation). My power supply is directly soldered to the leads on the strand.

Just for clarification, what pin to you have DATA connected to on the pi on this diagram:

You could also try to change LED_COUNT to 5 and run the script. If the first 5 lights turn on then you know it's likely a power issue.

Hope that helps!

Unfortunately, it seems that  connecting the ground straight to one of the ground pins on the rpi has no effect. When it's connected to the ground that goes to the power supply, at least some of the lights turn on (and usually some more do, after a while). This is true whether the data cable is connected to anything or not. 

All grounds should be connected together. So the light strand + power supply + raspberry pi gnd

Thanks for this, Paul!

I was able to recreate your project as well. I love the flicker effect you added in the script!
All I need to do is setup the wall and lights and lettering...

One thing I'd note for other people who might encounter the same problem with the LEDs not working. When people say they are using pin 18 on the raspberry pi, then they are usually referring to the GPIO pin which is physical pin #12.
I initially wired my LEDs to GPIO 24  lol.

No problem, glad you got it set up! 

I've definitely mixed up the gpio ports before as well, good note. If I get the time I'll put a schematic up so it's a little more clear where to connect it. I also want to add the blacklist file to this page and maybe even add an OS image that already has everything set up. 

Thanks to you I won the office halloween party costume contest! I told everybody how you wrote the python script, but people were mostly more into figuring out the messages lol =)

https://goo.gl/photos/FC6pM9MXcFJ75ur3A 

Awesome, glad you won!  Nice video, pretty cool to see it running on that version of the light strands. I was debating buying those since they are a little more Christmas-like.

Did you change the code at the end to randomly shut the lights off after randomly bringing them back on?  Just want to check if I have a bug in the code or not.

Yeah I added some messages to display at the end and for some reason wanted to turn off the lights first. 

I should have created an array of messages instead or something to iterate through.

This is an awesome project.  It made me go out and buy all the parts.  It took me a day or so to get everything setup due to lack of knowledge, but it is working now.  A couple of pointers for those interested in the project.
1. Buy some 2.1mm female plugs for the end of the LED strip.  This will make plugging in the power easier. The other end of the string has bare wires.  I believe these are for daisy chaining strings.  You'll want to protect there from touching each other so you don't damage the string. https://www.amazon.com/gp/product/B005CMP434/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1 (for example)
2. I bought the canakit bundle(Raspberry Pi, ribbon cable, power supply, case, breakout board, ribbon cable, bread board and some LEDS, resistors, etc.) and it included some additional wire connectors which were great for connecting the IO connections from the LEDs to the breakout board attached to the raspberry pi.  You only need 2 (the set is like 8 to 12 wires wide).
3. The end of the LED string with the female IO connector will have its loose red wire connected to the + side and the loose blue wire to the - side of the power connector plug.  Screw down tight.  This can then be plugged into the additional power adapter you purchased.
4. For the IO connections, connect the blue wire to any GND connection on your breakout board.  Mine came with a T shaped circuit board that connects to the Raspberry Pi with a ribbon cable.  The bottom of the board is screen printed with the pin out information.  Then connect the White wire to PIN 18.  I used the above suggested connector wires, but you can use whatever works.
5.  The script was very nicely written.  In it, it calls out the location of the lights on your string as "*******abcdefgh.....".  You can change this if your letters don't line up on your string.  I had to reverse all the letters due to the direction I had to run my string.
6. My Python knowledge is zero, but I'd like to find out how to allow the program to read multiple strings of words from either a text file or an array variable in the program so I can get it to say more.  I'm using this for a Halloween display and would love it to say more than the 2 sentences that are programmed.  I know it goes against the show, but would be useful for other displays.

Thanks for the response, those are some good tips!  If you want to spell out more than what's programmed, you could always just open a file and read each word line-by-line. For example:

If you file is called words.txt, the code could be changed to:

#flash lights with words from file

f = open('words.txt') 

for line in f:

    blinkWords(strip, line)

    time.sleep(1)

f.close()

Just make sure the words.txt file is in the same directory as the python script. Hope that helps!

Sorry to bother you, but I have zero coding experience and want to build this project for a friend's birthday - I can get it to run your code but which bit would this new code replace? Is it the #flash lights to word section or somewhere else entirely?

Hey Paul,

I'm a computer science grad and totally new to the whole electrical part to this project, so I have some questions. I have the lights and have a pi laying around, I believe all I need is a normal 5V 4A power supply (like a charger) and then I'll need to strip it and connect the wires somehow? Thats the part I dont understand. Like i said, I'm totally new to this type of thing but have an awesome idea for a project around my office! 

I'd love if you could dumb down the whole wire connection part if you have the time, or potentially link me to a resource that can help.

Great project!

Thanks, Tom

Hi Tom-

You are on the right track. You strip the leads on your 5V power supply (for the light strand) and solder them to the red (+5V) and blue (GND) leads on the light strand.  I suggest using a multi-meter to verify which is GND and which is +5V on the power supply wires so you don't accidentally mix them up and burn your strand up.  You then connect your Pi GND to the strand's other blue (GND) lead and your Pi signal wire to the strand's white (SIGNAL) lead.  Then power your Pi with a standard micro-usb power supply, run the code, and you should be set.

I plan to draw up some clearer schematics soon, I'll likely hand-draw them because the software I am trying to use is buggy.  Are you familiar with multi-meter or volt-meters? How about soldering?

Hope that helps, let me know if you have any more questions.

Thanks,

Paul

Thank you for this! We were just cleared to decorate our offices at work and this is going on the wall.

I know you mentioned you are planing on putting together some documentation and sorry if I am jumping the gun. 

Can you confirm I am on the right track? After setting up the rPi (I will be using a rPi2) and the Neopixel Library. How do I connect the LED strand to rPi? I was thinking of connecting (from the LED strand) the red wire directly to GPIO PIN 2 or PIN 4 (+5V), blue to PIN 6 (ground) and white (cut off the JST-SM) to PIN 18 (look this this is the PIN you used after reviewing your GitHub page). Once that is running, hollow out the C7 bulbs and hotglue them on top of the LED.

Am I on the right track or way off? The product has been ordered and will be here in two days. I wanted to make sure I have all my ducks in a row before I start.

Thanks again!

Hi Devin-

You're on the right track. For powering the lights, you should avoid drawing from the 5v+ on the pi. I used a separate power supply (5v, 4a) so I can safely drive all of the lights simultaneously. Just make sure all of the grounds are tied together.

I was able to drive the control signal directly from the pi. Also make sure you follow the arrows on the strand for connecting to the pi. Each light has a data-in and a data-out so the connection needs to be oriented correctly.

I am going to try and get more code updated and update the documentation sometime this weekend. 

Paul, 

Thank you for your guide. I was able to get it setup in my office. I think we are going to win for the best office decor!

You should post a photo of the installation!

Can you make a video of how you set this up? This project looks pretty cool.

Hi Anthony, I plan to make a video of the build sometime this week. I've made some good progress, it's just a matter of finding time to record.

Awesome man. I just haven't found a step by step video guide yet. I know nothing about coding so I am lost when I'm trying to set it up. Thanks

You have it running, but no pictures? :( 

I plan to add pictures and video this week!