and the contents of the box are a bonus. I like tic tac® candy. Lastly, "tic tac" is French for "Tick Tock", so
I've chosen a tic tac® box for an enclosure because it's the smallest that fits the components, it's cheap,
been carrying it around.
The end goal is to make a wristwatch (SOIC, SMD, etc...) but this prototype is already so useful I've
last longer on batteries as the voltage drops. Also, red doesn't affect night vision that much, a god-send
It's using red LEDs because they have lower forward voltage than other colours, so the clock will
accomplished with adjustments as small as parts in 100 million. That's over-kill since the crystal's drift
Ever since I've owned a digital watch, I've always wished that it had a way to adjust the clock's drift without
The tic tac clock's large single digit makes it very easy to read without glasses.
This makes it annoying for reading the time on a wristwatch or a phone; it requires pulling out the glasses.
The design decisions for this clock are that first and foremost I wanted a small, portable clock that I could
It can display pretty much all uppercase letters, punctuation and a few other doodles:
The choice of a 15 LEDs (3x5) display is to get the most functionality with the least resources.
Fits inside a tic tac® box:
All functions on the clock are operated using the single button:
Here's a video of the clock being operated to display the time (05:45:24) and then
the date (Sun Jun 22 2014):
N.B.: Crappy webcam that has issues with raster frequency. In person the display is solid.
use on the go. I'm far-sighted (bad eyesight, not clairvoyant) so I need glasses for looking at near things,
but I usually walk outside without glasses since I can see just fine past the length of my arms.
having to open the blasted thing and adjust a finicky variable capacitor, an endeavour that usually ends
up with a much worse drift. The Tic Tac clock lets the user adjust the drift so that very good accuracy can be
caused by temperature fluctuations is larger, but 2-3 seconds per month is feasible.
it's very apropos.
By the way, if you'd prefer you can use a 7-segment single digit display module instead, although the
current firmware 7-segment code isn't up to date. It will be fixed in a future revision, soon.
Very good accuracy can be achieved with drift measurement and compensation. In this video, two
clocks are running side by side, the one on the left is a breadboard prototype which has had its
time set just a few minutes prior, the one on the right in the orange tictac box had its time
adjusted four days prior. Both are in drift measurement mode which displays pulses every
second and minute and show better than 1/30th of a second synchronization. That's not
bad after four days. The pulses disappear for a short while in the middle of the video because
of the video camera's induced stroboscopic effect.
Here's the content of cheatsheet.txt, if you're curious: (you must be if you're still reading)
+--- Display modes ---+ +--------------- Action modes ----------------+
Here's a copy of the manual's Table of Contents:
- Action modes.
- Setting parameters.
- Setting the time and date.
- Setting the alarm.
- Setting the chime.
- Setting the pulse.
- Setting the beep tone.
- Setting the display speed.
- Setting the 12/24 hour mode.
- Setting the display seconds mode.
- Setting verbose mode.
- Setting the display refresh rate.
- Using the timer.
- Using the chrono (stopwatch).
- Using the dice.
- Using the animations.
- About the alternate parameters.
- Using the countdown timer.
- Using the two alternate alarms.
- Personalizing the user messages manually.
- Personalizing the user messages using RS232TA.
- Adjusting the clock's time using RS232TA.
- Editing the user characters.
- Setting the user characters with RS232TA.
- About adjusting the clock's drift.
- Adjusting the clock's drift manually with a calculator or CALCDRIFT.SH.
- Adjusting the clock's drift using RS232TA.
- Turning the clock's power off.
- Compiling the RS232TA optional utility.
- Various notes.