I think maybe I am obsessed with making Neopixel clocks. It's definitely becoming a problem.
Anyhoo, I bought a Neopixel RGBW 60-LED strip only to discover it was too big the perspex circular 'chocolate' box that I thought would make a neat transparent clock. I kind of left it for a while, then discovered hula-hoop-shop.eu who sell the all the components to make your own hula-hoop.
Obviously, a hula-hoop Neopixel clock was going to be the mutt's generative organs.
Side note: Really important - don't forget the '-shop' part to the above website address. Boy, you don't want to forget that, at work, and have to explain to your IT department. Trust me.
| Components | Src | Cost | Notes |
|---|---|---|---|
| Arduino Nano | 1 | £2.41 | V3 Compatible ATMEGA328P CH340 |
| Rotary Encoder RGB | 1 | £4.99 | Didn't come with the knob :( |
| Clear Plastic Knob | 2 | £0.66 | Plus £2.40 postage!!! |
| PCB Protoboard | 1 | £0.69 | Out of a pack of 10 |
| Adafruit Neipixel RGBW Strip | 1 | £29.43 | Black PCB 60 LED/m (ADA2837) |
| Tiny RTC I2C DS1307 | 1 | £0.99 | From a batch of 5 for £4.99 |
| A blue project box | ? | £?? | Don't remember where I got it! |
| 16mm Transparent tube x 3M | 3 | £13.28 | And £10.65 DPD Shipping cost! |
| 19mm Transparent tube x 1M | 3 | £5.17 | And the shipping cost... again! |
| 5v 2A PSU (UK Plug) | 1 | £7.99 | 5.5mm input jack |
The prices of the tubing were in Euros, so the cost in GBP is likely to fluctuate with the exchange rate.
I am a fool when it comes to checking the shipping costs. Like a real idiot I never check. In retrospect, I could have got the RGB Encoder cheaper from Hobbytronics along with the knob for the same postage. And I never checked the shipping costs from Hula-Hoop-Shop.eu until after I made the order - doh!
And, if I'd known at the start that the trick to reliably making a hoop was to use a slightly bigger bit of hoop to fit the ends in, I wouldn't have to have made a second order. On the plus side, I made a decent sized hula-hoop out of the tubing I had left over.
So, this is the bastard child of my RGB Rotary Encode and OTHER Neopixel Clock projects.
Honestly, there was a lot of hot glue used too. It's a bit of a blur. However, the Arduino Nano pin connections are documented in the source code.
Software-wise - this project relies on the following Adafruit libraries:
I wrote some fancy user instructions. The PDF file is here in the repo.
The RGB Encoder is designed to sit on a circuit board with through hole soldered connections. In this project, I soldered the legs to wires and then connectors.
The problem was I dropped the Controller box and it landed on the Encoder Knob. Since the Encoder itself is a push-fit construction of about 3-layers, the metal legs that hold them together are easily bent apart by enough force and the whole thing comes apart. So, one broken RGB Encoder and I had to buy a new one.
I wanted to make a perfect circle of plastic tubing to hold the Adafruit Neopixel strip. Hot glue didn't cut it. I found out that the normal approach is to use a connection bit that goes inside the tube - not an option in this project - or a bigger bit of the same tube that the ends go into. That is why I had to by 1-metre of slightly bigger (19mm) tubing and pay the stupid, expensive shipping cost again, to use about 10cm of that to make the connection.
However, I really like the finished product, so it was worth it.
Just as Jeremy says...
I was having reset problems when trying the more LED intensive display modes. Follow the Adafruit advice for powering Neopixel products, and get a 5v 2-amp power supply and have a big 100uf Cap in the circuit.
This is the default display mode after power on/reset.
White LED show the hour postions around the ring. Red is Hours, Green is Minutes and Blue is seconds.
Only Hours, Minutes, and Seconds are displayed. They pulse - full brightness on the change of second then they fade to black before the next second.
Looks cool but really distracting.
Hours (red), Minutes (Green), and Seconds (Blue) have a comet tail of 30-led which fade in brightness to black. When the colours overlap they mix.
Again, looks cool, but of all the modes, the hardest to actually tell the time. Especially when the comet tails are all overlapping.
Inspired by friends cheapo digital clock kit from Aliexpress. As usual, Hours are Red, Minutes are Green, and Seconds are Blue.
However, on even minutes the Seconds fill the entire circumference, one LED per second. Then on odd minutes it turns a Blue LED off per second.
The effect is that it fills and then clears the whole display every couple of minutes. Quite nice.
Same colour scheme as always except that Hours have 5-LED, Minutes have 3-LED and seconds have 1-LED. It feels almost counterintuitive because normally on the hands of a clock the hours is the small hand.
However, doing it the other way around just doesn't feel right somehow. Not my favourite.