I finally got around to taking some pictures and shooting some video of my assembled clock project. Above you can see it displaying time. Minutes are tracked by the blue LEDs in binary code. Each spire has three digits, when the inner and outer digits are lit it shows a binary five and the next spire starts counting. Hours are displayed as a red LED corresponding to the positions on an analog clock. Here it is 12:54.
After the break you can see the video of the clock in action, as well as a description of what went into the build. You’ll also find some close-up pictures and a bit more info.
I received the boards back from Seeed Studios two weeks and four days after placing my order. I’m shocked by the quick turn-around, especially since I selected the slowest shipping option available which itself could have taken three weeks.
I’ve been pretty busy with work lately but finally found a bit of time to populate a board and get some test code running. I’m happy to report that I made no design errors. Everything seems to work as planned! Well, that is after I discovered the tiny trace bridge between two vias which prevented ISP communications with the chip. A sharp razor blade fixed that right up. I understand that this type of manufacturing error is not uncommon and it doesn’t really bother me.
Above is a fast-motion video I made while populating the second board. I’ll be sending this one to my friend Christian who is going to lend a hand adding features to the firmware. Hand soldering the mostly SMD project wasn’t too hard, but it did take about an hour. If I were making any more than two of these it would be worth it to order a stencil and procure solder paste and an old toaster oven for reflow. Perhaps on the next project.
In my next post I’ll talk about adding the LEDs. This took a long time. The first spire took about 45 minutes, by the twelfth spire I had it down to around twenty. Here’s a peek at the final product:
How did I do hitting the mark from my concept?
A lot of work went into designing this board. Thanks to help from Chris Meyer and Devlin Thyne I ended up with what I think is a design that will be friendly for the PCB manufacturer.
The parts order from Mouser came in on Saturday. I printed out the copper layers and checked all of the footprints against the parts. Everything looks just perfect. Yesterday I placed an order with Seeed Studio for ten copies of the board. Hopefully I’ll have then in hand in about two or three weeks.
Click on the image above for a larger version of the artwork. Or you can checkout the Kicad files from my git repository. This board is tagged as brd-v1.0.
I’ve been working on a new clock concept and am far enough along to start sharing some details about it. I call it the Binary Burst. The latter is because I was inspired by some vintage starburst clocks and have settled on twelve spires as a reminder of that design. The binary moniker is because the readout will utilize binary code.
The illustration above shows my intended design. The time shown is 8:22. Each spire reads the minutes in binary shown as three bits made up of blue LEDs. The hour is noted as a red LED on the corresponding spire. If you saw the previous post about balancing the LEDs you may have figured out that the middle LED is a red/blue bicolor, with the rest being single blue. They are 5mm diffused packages that appear cloudy white when not illuminated. There should be some room for alternate display modes, but I’ll need to get working hardware in hand before I figure that out.
I spent a large amount of time over the Christmas break designing the circuit and laying out the board. This evening I ordered parts for four clocks. When they arrive, I’ll check that the footprints work and send the files off to a fab house for manufacturing. This is my first professionally fabricated PCB and I’ve put a lot of extra time in to make sure the design is up to snuff.
I’m actually seeing some results from my Light Programmer. I’m reading a photoresistor using the analog comparator on an ATmega168. Check out my previous post about the hardware, then join me after the break to see what I changed to get things working, and to see the demo video.