Compact LED display unit that functions as cryptocurrency ticker and doubles as a realtime YouTube subscriber counter.
In this project, we use a Raspberry Pi Zero W, some 3D printed parts, and a couple of max7219 display units to create a realtime subscriber counter in honor of our 100k milestone. With the recent rise and fall of Bitcoin, Ethereum, and other cryptocurrencies, we thought it was fitting to also make this display function as a cryptocurrency ticker. We've already coded this project for you, but you can modify our code to make this display do anything you want.
Step 1: Overview
Watch the video we created about it for an overview of the project, demonstration of what it can do, and a Q&A special at the end.
Step 2: Materials
We used the following materials to build this project:
2 x 4-in-1 max7219 Display https://goo.gl/WXEPUU
1 x Raspberry Pi Zero W https://goo.gl/r17sGH
12 x 2.5mm Bolt and Nut
4 x 3mm Bolt and Nut
1 x Micro USB wire
3 x Jumper wires
We also used these tools:
Allen Wrench Set
3D Printer (for the housing)
If you don't have a 3D printer, you can usually find one at a public library or school. There are also 3D printing services online like https://www.shapeways.com/
Step 3: Wiring
Five small wires were used to daisy chain the displays together. Each display has an in/out arrow that shows how data flows through the displays. Display 1 out should connect to Display 2 in.
Vcc => Vcc
Ground => Ground
DOut => DIn
CS => CS
Clock => Clock
We had to power the Raspberry Pi and the displays through the 5v GPIO pin on the Pi because they draw too much power through the micro usb. Here are the connections to the Raspberry Pi from display 1.
VCC => 5V
GND => GND
DIN => GPIO 10 (MOSI)
CSC => GPIO 8 (SPI CE0)
CLK => GPIO 11 (SPI CLK)
Step 4: Assembly
To make the housing, we 3D printed a few PLA parts. Our print bed was too small to print the entire front/back so we cut them into three pieces on the back side and four pieces on the front. A box cutter helped deburr the pieces so that they fit together better. This step is less critical if you plan on gluing the parts together.
The Raspberry Pi Zero W was slotted into the middle, back piece with 4 2.5mm nuts/bolts. The back has 4 counterbored holes so that the screws can sit flush. The housing parts have small tabs on the sides that allow you to screw them together with small 2.5mm nuts/bolts. A pair of tweezers made it easy to hold the small hardware in place.
The combined display unit was slotted into the front piece of the housing. The right side has a wider frame portion so that the wires can wrap around to the Raspberry Pi. the third front housing piece has to be screwed on after the display has been slotted in.
After connecting the display to the Pi, we add 3mm nuts to the 4 extensions on each side of the top piece. These nuts will be used to hold the housing together. Then, the housing was then carefully snapped together. We made sure not to loosen any wires connected to the Raspberry Pi.
The back piece of the housing was screwed on with 4 3mm bolts. These bolts will attach to the nuts that you placed in the previous step. If you want to give the housing some extra protection, you can wrap the seam in a piece of black electrical tape like we did.
Step 5: Coding
We've posted full instructions about how to code this project on Github: https://github.com/HackerHouseYT/realtime-subscrib...
If you have any questions about running the code, make sure to leave post an issue on the Github page. Someone should be able to help. If you added a cool, new feature, make a pull request and I'll merge it in!
Step 6: Resources
Some resources for this project are provided below:
Find all the 3D printable parts and code for this project on our hackster.io page: https://www.hackster.io/hackerhouse/realtime-cryp...
Follow Hacker House on Instagram:
If you liked this project, subscribe to Hacker House on Youtube: https://goo.gl/qHjz4j
Visit our website for parts and project updates: https://www.hackerhouse.site/
Thanks for viewing our instructable!
Aaron @ Hacker House