If you want to proclaim to the world that you’re a geek, one good way to go about it is to wear a wristwatch that displays the time in binary. [Jordan] designs embedded systems, and he figured that by building this watch he could not only build up his geek cred but also learn a thing or two about working with PIC microcontrollers for low power applications. It seems he was able to accomplish both of these goals.
The wristwatch runs off of a PIC18F24J11 microcontroller. This chip seemed ideal because it included a built in real-time clock and calendar source. It also included enough pins to drive the LEDs without the need of a shift register. The icing on the cake was a deep sleep mode that would decrease the overall power consumption.
The watch contains three sets of LEDs to display the information. Two green LEDs get toggled back and forth to indicate to the user whether the time or date is being displayed. When the time is being displayed, the green LED toggles on or off each second. The top row of red LEDs displays either the current hour or month. The bottom row of blue LEDs displays the minutes or the day of the month. The PCB silk screen has labels that help the user identify what each LED is for.
The unit is controlled via two push buttons. The three primary modes are time, date, and seconds. “Seconds” mode changes the bottom row of LEDs so they update to show how many seconds have passed in the current minute. [Jordan] went so far as to include a sort of animation in between modes. Whenever the mode is changed, the LED values shift in from the left. Small things like that really take this project a step further than most.
The board includes a header to make it easy to reprogram the PIC. [Jordan] seized an opportunity to make extra use out of this header. By placing the header at the top of the board, and an extra header at the bottom, he was able to use a ribbon cable as the watch band. The cable is not used in normal operation, but it adds that extra bit of geekiness to an already geeky project.
[Jordan] got such a big response from the Internet community about this project that he started selling them online. The only problem is he sold out immediately. Luckily for us, he released all of the source code and schematics on GitHub so we can make our own.
Not just another steampunk fashion statement, [Johngineer’s] ChronodeVFD wristwatch is as intricate as it is beautiful. Sure, we’ve seen our share of VFD builds (and if you want a crash course in vacuum fluorescent displays, check out Fran’s video from earlier this year) but we seldom see them as portable timepieces, much less ones this striking.
The ChronodeVFD uses a IVL2-7/5 display tube, which in addition to being small and low-current is also flat rather than rounded, and features a transparent backing. [Johngineer] made a custom board based around an AtMega88 and a Maxim DS3231 RTC (real time clock): the latter he admits is a bit expensive, but no one complains about left-overs that simplify your design.
The VFD runs off a Maxim MAX6920 12-bit shift register and is powered by a single alkaline AA battery. A rechargable NiMH would have been preferable, but the lower nominal voltage meant lower efficiency for his boost converters and less current for the VFD. [Johngineer] won’t get much more than 6-10 hours of life, but ultimately the ChronodeVFD is a costume piece not meant for daily wear. Swing by his blog for a number of high-res photos and further details on how he built the brass tubing “roll cage” enclosure as well as the mounts for the leather strap.
Until recently, watches have been entirely mechanical where each wheel, gear, and mechanism representing a milestone in our understanding of precision manufacturing and timekeeping.
Today it is nearly impossible to find watchmakers to service or repair vintage mechanical pocket and wristwatches, so we have to do it ourselves. Learn to repair vintage mechanical watches. You can do this and we’ll show you how.
PCB fab can vary greatly depending on board size, number of layers, number of copies, and turn time. PCBShopper will perform a meta-search and let you know what all of your options are. We ran a couple of tests and like what we saw. But we haven’t verified the information is all good so do leave a note about your own experience with the site in the comments below. [via Galactic Studios]
A few days ago [Andrew] contacted us to offer his help for the design of the mooltipass project case. While introducing himself, he casually mentioned his OLED watch that you can see above.
The watch is based on the low-power MSP430F microcontroller from Texas Instruments. It can consume as little as 1.5uA while maintaining a real-time clock and monitoring interrupts. It also uses ferroelectric RAM, which doesn’t need any power to retain its memory contents. That means there’s no need to set the time again if you remove the CR2016 battery that powers the watch.
[Andrew] chose an 0.96″ OLED display that only consumes up to 7mA. He also included an accelerometer that allows him to interact with the watch through its single and double tap detecting feature. He modeled his PCB using EagleCAD and the whole assembly using Sketchup. Most of the components were soldered in his reflow (toaster) oven. The final result is a mere 8.8mm thick and looks very professional in our opinion.
Our mouth is still agape after digging through [Tom’s] watchmaking blog. This gentleman spent several years designing and machining his own mechanical wristwatch. A dozen years ago or so [Tom] answered an ad for an apprentice watchmaker. He worked on watches and came across a book that detailed how timepieces are made. He was told that no-one does it like that anymore, which only fed his curiosity. What he came up with is, to his knowledge, the first timepiece every made in Australia.
It’s no secret that we have a thing for clocks. But we feature digital timepieces almost exclusively. We’ve love mechanical watches too but don’t see them as hobby projects very frequently. After looking at what goes into the mechanism it’s not hard to see why.
[Tom] was faced with a variety of challenges along the way. One of the biggest was having to come up with tools that would let him perform the precise milling work necessary to achieve success. You’ll want to read through his movement design and manufacture posts. He laid out the plan in CAD, but ended up using some hacked together milling tools to get the job done.
[Mats Engstrom] wrote in to tip us off about his build. The design goes with LEDs which is nothing new. But unlike previous offerings [Mats] didn’t go with one LED for each minute. When the touch sensor in the middle of the watch is activated the twelve LEDs on the face will let you know the hour and the nearest five minutes. A video of this is embedded after the break.
The design uses three different circuit boards. The bottom board is the largest and provides slots through which the wrist bands can connect. It also serves as one of the two battery connectors. The second PCB is a spacer with a cutout for the coin cell that powers the device. The top board is where all the magic happens. It’s dual sided to host the LEDs and touch senor, with the PIC microcontroller and support circuitry on the other side.