So as you can see, I’ve been working on some projects waiting for all the paperwork to come through for a building and construction. This is one of several ideas I have rattling in my brain and unlike the grain art project that took 5 times longer than I expected it to, I knocked this project off pretty fast. (maybe 5-6 hours total)
I call it a “Barrels Produced” Display and I’ve seen other breweries do this with a chalk board or dry-erase board before, so I borrowed the idea and decided to turn it into an electronics project. The simple idea is that any customer can see the amount of beer we will have produced from day one at any snapshot in time. I remember when Wynkoop Brewpub released their 3000th batch of beer they appropriately named B3K. They have a large manually updated display over the doorway to their brewhouse that can be seen in the bar.
The project is based around this large format quadruple digit (7-segment) display panel that I purchased from adafruit.com. Like all electronic projects, they start on a breadboard. I prefer to use arduino for my processing as I’m most familiar with the programming. Raspberry Pi makes a more powerful and versatile processor, but that would have been overkill for this project. If I were REALLY good, I would have just done this with ATMEGA from scratch.
On bigger projects I spend a lot of time writing psuedo code first and spend several days thinking about efficiency of the program before finalizing the circuit, then you are left with implementing the plan. This project was small enough that I just did the programming on the fly.
There is no one-way to tackle my problem, but I went with one incremental button per digit (1’s, 10’s, 100’s, 1000’s) and a subtracting one, just for kicks. The program worked great until I realized that when I powered off the display the counter always reset back to zero. That wouldn’t be fun, re-keying in the latest display everyday. (I would need a dry erase board next to this display, which defeats the whole purpose).
After some online research, I realized that I could just store the value in the EEPROM and it could be called back up after power loss. According to the internet (and it’s never wrong!) I can only write to the EEPROM bits 100,000 each before they will start to fail. But some quick math shows that even if I update this every single day then it will last 274 years! Even if I update it once an hour, it will still last 11.4 years! I think I’m safe.
Then of course was the enclosure which makes sense to custom laser cut/engrave. I probably spent less than two hours on the laser for this, which is fast for I’m still getting the hang of the thing. As you can see it runs neatly off a 9VDC battery and I wired an easy toggle switch so we can turn it on and off.
Overall, it was a super quick and fun little electronics project that had a final purpose.
***Editors Update 2-28-18***
The Arduino Pro mini became corrupt. I hard soldered it. so, after unsoldering and putting in headers so I can plug in new cpu, a single download and reset and it was working again.