Tuesday, March 13, 2012

Wise Clock 4 Dual screen chronometer

Update (June 30, 2014): This chronometer clock is complete now. It is also available in the two-sided (two-faced) version, aka "Kandinsky", as shown in these photos.

This chronometer, inspired by the Doomsday clock by Wyolum, is made with a Wise Clock 4 board (available for sale here) and two 3216 displays from Sure Electronics.

Its main feature is the odometer-style rolling of the digits when they change.
The time is updated once a second, based on the 1Hz interrupt signal from DS3231, as described here.

As shown in the video, one button is used to change the display brightness, another button is used for changing the font, and the third is used for switching between rolling style and static style.

By using the bigger (5mm) 3216 displays with the same setup and software, this clock can be easily read from a distance of at least 100 feet (30 meters).

Source code is available here. The current version does not allow setting up the time and date from buttons.


  1. Hi Florin, will be available for download?

  2. I will publish the code as soon as I add the ability to set the time from buttons (in a couple of days).

  3. Very nice Florin. How did I miss this earlier?


  4. Hello Florin,

    What a coincidence: it appears that we both share the same name -- I am Fabrice Florin, living in California.

    I just discovered your great blog, Wise Time with Arduino and am interested in this Wise Clock 4 Dual screen chronometer:

    I would like to buy a Wise Clock 4 kit, but one that includes two displays and is already assembled and tested, with SD card and USB cable, for control by an Arduino Duemilanove.

    Before I can place an order, I have a few questions:

    1. What are the dimensions for each dual display? how many LEDs per display?

    2. How can I control it with Arduino? (via USB? with direct pins? is Bluetooth required?) Are the two display daisy-chained, or do I have to control them separately?

    3. Do you know of any Arduino libraries for displaying alphabetic characters, rather than numbers? Do the libraries include effects for scrolling the letters? or using your odometer-style effect?

    4. What is the difference between Wise Clock 3 and Wise Clock 4? Is one smaller than the other?

    We are now looking for an Arduino-compatible solution that can show short phrases on an LED display (see my Arduino Forum post). We have some size constraints: the LED display needs to be between 6" and 8" wide, by about 2" high. We are hoping to show up to 10 characters at a time on the display, either by scrolling or other visual effect (with a minimum resolution of 8 x 12 pixels per character).

    Do you think that one of your Wise Clock products could match our goals? If so, what is your price and shipping cost for delivery to Mill Valley, California?

    I would also love to hear more about you. Where are you based? What kinds of Arduino projects do you do?

    We are creating an interactive art piece called the Pataphysical Slot Machine, which lets you get instructions from the future, at the touch of a button. You can see the art in progress and read more about it here:

    Thank you!

    Fabrice Florin

  5. Hey Fabrice,
    Thanks for your interest in Wise Clock 4.
    Here are my quick answers to your questions. For more clarification please PM me (email address in the top right corner of this page).

    1. The double display can come in 2 dimensions:
    small display (3mm LEDs) is 10" x 2.5"; large display (5mm LEDs) is 19" x 4.75". Each double display has 64 x 16 bi-color (thus showing red, green and orange) LEDs.

    2. You don't need an Arduino, since Wise Clock 4 itself is Arduino-compatible (software-wise). Upload the sketches (if you want to extend the functionality and add new features) using an FTDI cable or breakout, directly from Arduino IDE, through USB, like for a regular Arduino.
    The 2 displays are daisy-chained, bat from the software perspective, they are seen as an array of LEDs (pixels), each addressable individually.
    Bluetooth is not mandatory, but a nice option for remote-control (e.g. sending text to the display, sending commands).

    3. The software contains the definitions of alphabetic as well as numeric characters. The video for the chronometer shows just numbers, but check my other videos (on my youtube channel) to see characters scrolling.

    4. Wise Clock 4 has one added feature over Wise Clock 3: support for XBee devices, like WiFly (to access the internet through WiFi), GPS, Bluetooth.
    The dimensions of the 2 boards are identical.

    I am in Toronto, Canada. Regular shipping for my kits is already included in the price.

    To learn more about my projects, please browse through this blog.

    If you think that the 32x16 display is too big for your needs, please consider the (single color) 32x8 LED display, as used in the BookClock project:

    Again, please PM me and I will offer you more details.

  6. Hello Florin,

    I recently bought the Wise Clock 4 kit and just finished building it. Looking to expand it to the dual display. Did you manage to get the code working to assign time and date using the buttons?



    1. Yes, the time and date can now be set from the buttons (select menu items SETUP/TIME and SETUP/DATE respectively).
      For the dual display, you will need to modify a line in HT1632.h, recompile and upload the sketch.
      Also, if you use the 3mm displays, to connect the second screen you will need a 2x8 right angle male header soldered in the spot beneath the left display connector.

  7. Welcome FlorinC. I just installed your WiseClock 4 I have uploaded soft: https://wiseclock2.googlecode.com/files/WiseClock4.zip and everything works great. But if https://wiseclock2.googlecode.com/files/WiseClock_120707.zip Upload a compilation is OK, but verification after programming with an error: "Binary sketch size: 62216 bytes (of a 63488 byte maximum)
    avrdude: verification error, first mismatch at byte 0xf000
             0x00! = 0xff
    avrdude: verification error, content mismatch. "
    My version of the Arduino IDE to 1.0.3
     Please help me, where is the error. I care about using two displays. Sorry for my English

    1. Hi,
      What processor are you using?
      Are you using the FTDI cable.breakout to upload the sketch?

    2. Atmega644PA PU processor, I used the cable on the chip Prolific PL2303 and found that there is a problem. I changed the FTDI cable and upload https://wiseclock2.googlecode.com/files/WiseClock_120707.zip did and everything works ok when I set the file HT1632.h line "# define NUM_DISPLAYS 1".

      But when I set "# define NUM_DISPLAYS 2" display is black and does not work. Is there anything else I need to change???  Thank you for your prompt reply. This clock is great.

    3. I started the clock with 2 displays. The problem was the version of the Arduino IDE. After changing the version of 023, everything works ok :-)

    4. I guess the code was not updated to cover Arduino 1.0 and later.