Neopixel Notifier

Neopixel Notifier

I was looking for solutions to make a notifier to for various projects. I while back I made something similar with a small OLED screen but this time I wanted something more “wife friendly” so I set out. I had a few neopixel WS2812 RGB LEDs laying around and some NodeMCU ESPs. I went with a NodeMCU board for simplicity of micro USB power already onboard but you could use any ESP for this project and it should work.

So I started searching how to cobble them together and I found

Which led me to… which led me to here

This was perfect. I took the ESP8266 and connected it via MQTT to subscribe to a topic for changing the colors of a WS2812 (neopixel). All you do is send RBGW code (255000000000 is red for example) via the topic.

The code works great, after changing the topics and such. But its not up to my liking. So here is my re-coded version. I basically made it easily editable, add all the variables to the top.

Now I can slap an ESP and the neopixel in something for notification. I just have to remember what each color means and I will let Node-Red send the changes when needed. Fucking awesome. I can use this for temperature, rain, mail delivery, change the color if someone has ever pressed the doorbell that day…its endless. Only downfall is one alert overrides the previous color (is that really a downfall?) so the alert is “over-written”. So if you are going to use it for say timing on something or modes of the day or what have you, single project use, then it should fit the bill.

I happened to have to have a 3D printer and came across a really nice model of a lamp (Bioh Lamp) that I decided would work perfect as a notifier. After I made some modifications and added NodeMCU standoffs it worked perfectly. Don’t get me wrong it took a few tries to get the spacing right and I tried a few approaches before using the NodeMCU so the older standoff for centering the WS2812 is still there. Unfortunately the author has is locked up pretty tight and used the Creative Commons – Attribution – Non-Commercial – No Derivatives license so I cannot share it.

I used an old Apple iPod USB cable and chopped it up wired it to the boards. Also repurposed an old iPhone charger to use as the power supply. Perfect!


Code below.

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I2C Scanner for ESP8266-01

I2CI am semi new to programming electronics. Straight amateur thats for sure, but I know enough to be dangerous. I have been trying to figure out how to get my MPU6050 sensor to work with the ESP-01. I couldn’t figure it out for the life of me. I have tried all kinds of things. I started this endeavor back when there was no Arduino IDE support for the ESP (a while ago). It was AT commands or LUA. Now that the Arduino IDE can be used it makes things much easier (I initially had issues getting it to work on my Mac). But sometimes there is a catch. I have noticed that most of the Arduino sketches will work but with a small minor tweak here or there. For example most tutorials I have found people are using the ESP8266-12. The model 12 has multiple pins available for TX & RX, the 01 model does not. The 01 model is the cheapest and happens to be what I have.

I found out it was pretty easy to change the sketch to get it working, most of the time. In the case of say I2C you have to specify the pins used for communication. The 01 only has two free pins, GPIO0 and GPIO2. Those can be used as inputs/outputs for a relay or say an LED. Or, you can use them for I2C communication. You need to specify the pins used in the sketch though. I am pretty sure this is beginner stuff, but hey I just figured it out.

Load up the default I2C scanner sketch and where you see Wire.being()  change that to Wire.being(0,2)  and you are now good to go. That should get you going on almost any I2C based sketch for Arduinos. You wont be able to use the pins for input/outputs (as far as I know) but now you have I2C.

ESP8266 and the Arduino IDE on macOS

ESP8266 and the Arduino IDE on macOS

Doesn’t work. Fucking go figure. There’s always something to cause a problem. If you have been following the last few posts I’ve made you would see that I have been working on ESPs all weekend. I finally got a new TTL adapter that works with the ESPs and have been playing with ESPlorer and LUA code. I decided to switch over to the Arduino IDE since there seems to be more support and tutorials for it. Well it won’t connect.

That is what I am greeted with. Well after about an hour of trying different shit I found this tidbit on the Github for Arduino issues: This is because esptool-ck doesn’t work with PL2303 based converters on OS X. Fucking great. Thats what I just bought, so I could flash the chips again. So I fired up Virtual Box and Windows 7, downloaded/installed all the needed Arduino shit and drivers and blah blah. Opened a blank sketch in the IDE, selected the ESP board and hit upload. BAM! Shit worked. Took daaays, but it worked. Fucking Apple. Looks like I’m stuck to a Windows machine no matter what I do. Sad face.

Update: So after flashing via Windows in Arduino IDE and it working I went back to macOS to try again. I changed “ck” to “nodemcu”, which didn’t work at all. So I changed it back, thats when it started working. I still had to do the reset-flash-dance. Ground GPIO02 and reset, once booted release GPIO02 and set it high, or let it float. That should put you in bootloader mode so you can flash via the Arduino IDE. I also noticed that I cannot switch back and form between the IDE and ESPlorer. They don’t play nice together. If I want to switch I have to reflash the ESP firmware. That sucks. Picky ass modules.

I can finally flash again

I finally did it! I was able to flash my ESP8266s again. It only took months and a bunch of scratching my head – then banging it against a wall. I cannot even really remember where I left off with my programs, but I do recall I stopped because I wasn’t able to flash my chips anymore.

WiFi Module ESP8266-01

That was a big problem obviously, and I do not know why it started as all was well in the beginning. I originally had ordered a few ESP8266-01s and some Arduino Mini Pros. I figured they would work well together. To go with the Mini Pros and ESPs I nabbed a USB FTDI programmer and it worked fine when I initially got it. I was able to send AT commands to the ESPs and program my Mini Pros no problem. Then I started playing with flashing new firmware on the ESPs to try NodeMCU, and I think thats where everything started to go downhill. The FTDI and ESPs would stop communicating half way through flashing. Eventually I couldn’t flash or upload anything anymore. It just wouldn’t go. Fast forward a months later and I ran into a few posts that mentioned the FTDI chips are unstable with the ESPs and won’t work. Hmmm. They all recommended using a USB TTL adapter instead.

So thats what I finally did, purchased a USB TTL adapter off Amazon for $6. I got the Armorview PL203HX adapter. USB plug on one end and four breadboard connectors on the other for PW, GND, RX and TX. Simple. As soon as I got it I plugged it in and… nothing. A ls /dev/tty.*  yielded nothing. WTF. I probably need a driver. Yup, the PL2303 driver was needed in my case. Installed that and plugged the adapter back in and now I see it tty.usbserial . Nice and generic. First thing I tried was flashing the AT firmware to an ESP. And it worked!!

I can now flash firmware to the ESPs again, and the Arduinos if I wanted to but the FTDI still works fine with those. For those that want to know; I use a breadboard power supply for powering the ESPs and Arduinos. I only use the USB adapters for communication. You can and I have done it without it, but it is just way more stable to use the extra power supply. The adapters don’t have the juice, especially for the ESPs. Now I can get back to tinkering again.

See this post for how I got the ESP to send MQTT data

See this one for how I got send and receive to work with MQTT

Send and Receive MQTT data


I made a post last year on how I was finally able to get the ESP to send MQTT data. I had forgotten all about that when I was able to flash the chips again, so I started digging for how to do it. I basically came across the same code somewhere else (can’t remember where), but this time I was able to get send and receiving to work. Decided to share. Once uploaded to the ESP you can see the printed results in the buffer window (I use ESPlorer). Code is below.