Adafruit Builds The Back To The Future Time Circuit Display


If you were growing up in the ’80s this display panel will be instantly recognizable. It’s the time circuit display which [Doc Brown] built into his 88 mph per hour DeLoren time machine. If this still doesn’t jog your memory (or if — *gasp* — you’ve never seen the movie Back to the Future) take a gander at the montage video below.

The thing is, if you look really closely you’ll find this isn’t an exact match. Hackaday alum [Phil Burgess] put together a guide for Adafruit that shows how to build this version. But the movie actually cheated when it came to the month display. In production the month was displayed as alpha characters by painting glass slides. To make that happen here you would need some sixteen segment modules (like in this project). But we don’t mind the change one bit. The nostalgic look stands on its own even if it’s not an exact replica.

We’re sure you’ve figured out by now that this is backed by a dead-accurate real time clock (chronodot) and powered by a Teensy microcontroller board. Which means you can use it for just about any of your timekeeping needs.

37 thoughts on “Adafruit Builds The Back To The Future Time Circuit Display

    1. From the unreleased 5th sequel in the series… Doc is low on money after the car got wrecked during an unfortunate incident with gravity and he has to go to dealextreme to get a new one. Since he can’t afford the genuine article, he settles for a DeLoren (with free shipping). Many happy satisfaction guarantee.

        1. Yeah I also don’t understand this increasing incessant need to have steps of a procedure spread onto many separate webpages – web designers have forgotten that scrollwheels and touchscreen drag-scrolling etc. are there for a reason!

  1. so why not use sixteen segment displays to get the month to match? I understand that you would have to use something else besides pre-fab breakouts and would have to write some extra code that might be outside the scope of an Arduino library, but come on….. it’s the details that make projects like this special and it seems like a lot of effort invested just to come up short in the end

      1. Honestly, this is something I’ve been contemplating building for a while….I just don’t have a good use for it at the moment (besides collecting dust) so I’ve been devoting time to things that need to get done

    1. I could see someone like Adam Savage, with his near-unhealthy movie prop obsession, doing that much work to get it to be authentic. For a general-purpose tutorial, however, this one is pretty awesome.

    2. Because standard alphanumeric digits do not exist in the same size of the numerical ones. You should have them made for you.
      Also in the original movie they were *not* true displays, it was just a lamp with a mask to appear like segments. If you look at the movie you’ll see that JUL and DEC are not possible to be drawn like that in sixteen segments displays.

      1. I found some .5″ ones on Mouser…. Slightly smaller, but not that noticeable.

        You do have a point about forming J’s and D’s…but the J would only be slightly different (Not sure you would notice it unless you were looking for it). The D would be noticeable….but still less so than replacing alpha chars with numbers. Even though they weren’t real displays in the movie, doesn’t mean it isn’t possible to replicate the effect without a lot of extra work

        1. I made my own replica and i have smacked my head on this :)
          I searched the displays on Rs/Distrelec/Farnell without luck and read another blog where a guy managed to order such displays from a company that made a custom lot. You seem to have better luck than me…
          I settled doing them with 7-segs, at least they have the same size and color than the rest. But yeah, alphanum. would look better for some months.

  2. Everyone always gets the programming on the 7-segment displays wrong. The 6’s don’t have the top piece (as clearly shown in the ‘Oct 26’ date in the preview of the linked video). This seems to be a common mistake; even the digital version in the recent-ish Telltale video game had that error.

    And I’m with Matt, just … use the proper 16-segment displays for the text once you’re going to this level of effort.

  3. The labels look nothing like what a classic Dymo label maker produces (which is what was used in the original). A “Xyron applicator” didn’t exist in 1985. “Hero prop” or not, If you’re gonna spend the time wiring up 80’s-style LED displays, then at least use the proper labels from the time.

  4. I tried something similar last year as a birthday cake for a friend.
    I came across the same problem with the months.
    The problem was not only to find a fitting 16 segment modules but that you would need more driver chips to make them work. Also the color and the brightness did not match.
    So i used the 7 segment modules for the months too. It worked out fine except for march and may, you can’t display anything like a M on one 7 segment module, so
    i replaced the M caracter with one of these instead
    Here are some photos and videos. I haven’t had time to translate it so it’s only in german.

  5. Ironically I used to know a guy where I lived that converted a car to run off of gas and styrofoam. It would turn the gas into a napalm mixture. He actually got really good mileage, until the pistons and header fused after about eight years of running it. For giggles he had to setup to look like the DeLorean.

  6. Don’t need money – don’t take fame
    dooon’t need no credit card to ride this train
    it’s strong and it’s sudden, and it’s cruel sometimes
    but it might just save your life…

  7. “88 mph per hour DeLoren” All wrong!!!!

    First, mph per hour??? :-D duplicating the information makes it wrong.

    And then… DeLoren???

    Maybe I am overreacting? :-P

  8. i was under the impression that with all the 3D printing going around these days people could make thier own alphanumeric displays to thier own liking?????
    i mean you could even change out green for limegreen or red for redish-orange ect

    or even RGB alphanumeric display. anybody?

    1. Whhhaaattt? You don’t 3D print displays. You can only make solid shapes, you would need to print translucent colors for one, which im not sure thats even being done yet.. AND you would need to print in 2 different mediums – opaque plastic, translucent colored plastic and you would have mold in the LEDs, which I guess SMT LEDs would work. But there are so many “not happenings” in what you just pondered about 3D, I don’t even know where to begin… As great as #D printing is, its going to have to come a long long way before printing displays!

      1. It’s been done. There are translucent print materials in both PLA and ABS, and you can print them in seperate runs to fit together post-print, or possibly using a dual extruder. Scale is a factor because of resolution, but has a few results for “7 segment”.

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