Custom Tron Disc Mod

In this Instructable, I cover modding the store-bought Deluxe Identity Disc to an upgraded version with 64 leds, controlled by an AVR MCU. The upgraded version is costume-ready and would be an excellent addition to your Tron costume - it'll also look great on your desk/dresser/etc.

My 7 year old daughter watched Tron:Legacy with me on Father's day and decided instantly that she wanted to be Quorra for Halloween. I knew the costume would be a decent bit of work, and I don't sew (although I will be getting assistance making the costume - hopefully a forthcoming instructable) - I decided to start with the Identity Disc.
I managed to find an identity disc at Target for $9 on clearance (they can be found on Amazon for $12 as of the writing of this article). However, when we brought the disc home, I was seriously disappointed at the lack lighting. So - like any good father would do - I set out to upgrade the disc.

Please note that this project does not preserve the original sound - I'd really like to include something, but didn't find any AVR examples I really liked. If you have any suggestions for sound inclusion - please share!

Before I start the article - and before people say they can't do this themselves - let me be clear about my qualifications. I'm a Software Developer (.Net). I'm not an electrical engineer, my soldering skills are sub-par, and even though I'm a developer - my AVR code is probably horrible. If I can do it, anybody with a lot of patience and time can as well.

And take it easy on me - this is my first Instructable!

When I started my research - I ran across this article: Tron-Disc-with-NET-Microframework. Fantastic implementation - all LEDs can be controlled individually, adjustable brightness. Then I noticed the huge board in the middle. And the expensive cost of the hardware, etc. I needed something that wouldn't break the bank, and parts that I could fit in the disc.

But first - let me leave you with a little teaser video. This is what the device looks like with the V1 firmware.

Also - if you're interested in a look at the costume - here it is!

Step 1: Materials & Tools

Materials:

• Tron Deluxe Identity Disc
• 3 x AAA alkaline batteries - any battery source between 4 and 5.5v would work, but you're limited on space
• 64 LEDs (I bought a set of 100 blue on Ebay for $3.50 including shipping)
• ATMega328/168 or ATTiny45- I was able to get free samples from Atmel - warning - they're much more difficult to obtain than Maxim
      Any AVR chip that supports SPI/USI and has an additional 2 input pins would probably work as well
• Max7221 or Max7219 LED Display Driver - I was able to get free samples from Maxim - they provide samples fairly freely
      I have not tested with the Max7219 - but from what I've seen online, these should be interchangeable
• 50+ feet of 30awg wire - seems like a lot - but you'll need it
• RSet Resistor - I needed a 15k resistor - this helps the LED Driver determine what current/voltage to use
      See this page for more information on values
• Solder (I suggest something small like 0.032)
• Perfboard - a small sheet is all you'll need.
      You'll want the kind with the copper rings. Veroboard would probably work as well, but it's more expensive
• 24 pin DIP IC Socket (Optional - used for the Max7221 - I don't trust myself to not fry the IC)
• 28 pin DIP IC Socket
• Two pens with springs
• Hot Glue Sticks
• cyanoacrylate
• Magnetic Reed Switch - I used the glass kind
      For the second disc, I used a COTO-20 I purchased from eBay. For the first disc, I harvested one from a broken child's toy

Tools:
Soldering Iron - I'm not using anything fancy - just an $8 iron from RadioShack
Soldering Helper - Not sure what it's really called, but it comes with the RS Iron - it's a thin tool that I used to help route wires, wrap wire, etc. It proved invaluable. This or a similar tool will come in handy.
Dremel, cut off disc and engraving tip (Optional, but highly suggested)
Wire cutters
Wire stripper (Optional - finger nails work very well on 30awg)
AVR Programmer - I use a $6 USBASP programmer I found on eBay
Silver Sharpie (Optional)
Hot Glue Gun
Pliers - ideally a small pair

Comments

[fisher_g]

This is a very informative instructable. Thank you for the details you provided. Physically putting this together will be relatively easy for me (thanks in large part to your instruction), the code is where i am falling flat on my face. I haven't looked at coding in nearly 10 years. I sort of understand portions of it, but not quite. I am interested in understanding your code line for line, but also in getting it installed onto my ATtiny45. Do i need to use your code files to do this or can it be done using only the hex file? I apologize in advance for the naive ness of the question but, this is my first venture into MCUs.

[cubeberg]

The MCU can be programmed with just the HEX - you shouldn't really need to do too much to get that set up. You'll need to set the fuses correctly as well (8mhz internal clock). There is also a great tutorial (I think I linked to it) on programming AVR using Eclipse.
If you run into trouble - let me know.

[fisher_g]

Thank you for your reply. I just finished compiling the code in Eclipse. Should the HEX that I generate be the same as the HEX that you generated? I was interested in seeing if I had do everything correctly, so i compared the two HEX files and they do not match. I am still waiting to receive my AVR Programmer. Will that effect what the hex code is, or have i maybe done something wrong?
Thank you again for you insight!

[cubeberg]

I'm not surprised. My files are over a year old so you're probably using a different version of the compiler. Plus - depending on the compiler options you chose. It also might through in date as well. If you have problems, you might try burning my hex file, but what you've got will likely work.

[bdoyal]

Question before i start reading into the instructable. How much alteration is made to the top half of the disc? Are any parts removed and if so, which?

Also, is there any room left inside the disc for, i don't know, a data storage device?

[cubeberg]

Check out steps 2 through 4. There are no external changes, but the entire contents of the disc are gutted to make room for the new electronics.
There's probably some room for a flash drive, especially if you remove the case (although you'll need to insulate it with some electrical tape to protect against shorts).

[bdoyal]

So basically we go with the smooth the inside with a dremmel approach.

I really like this instructable, you only spent like 50 bucks and got a good looking device.

You click the button to change the animations right? So i could leave the blade one idle and itd stay on?

[cubeberg]

Correct - unless the magnetic reed switch (optional) is connected or the button is pressed, the device will stay on the blade animation. The code is pretty easy to modify as well, so more animations and functionality would be easy to add.

[bdoyal]

How exactly did you get the samples?

[cubeberg]

Check out http://www.ladyada.net/library/procure/samples.html for general sample info

To avoid the hassle though - I'd suggest this site: http://www.taydaelectronics.com/ - they sell the Attiny85 (will work with the attiny45 code) and the Max7219. You can pick up some perfboard and resistors as well.

[googiecarr]

This is awesome! I'm going to go buy the stuff and start making it tonight! Hopefully I can finish it before Halloween.

[jive2jazz]

Is there any reason you would want to avoid the low power version of the ATmega328? the atmega328P?

[cubeberg]

I actually used the ATMega328P-PU for the project. The Max7221 used to control the LEDs operates between 4 and 5.5v, so as long as you power the circuit with those constraints in mind - you should be fine.

[chunk_change]

You should totally make one a clock!!!

[fkhalsa]

Cool!

Tip: If you haven't already come across it, EL wire is pretty much a necessity for any properly outfitted Tron costume.

http://www.google.com/search?gcx=w&q=el+wire+tron&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&hl=en&tab=wi&biw=1280&bih=929

The aqua and the orange are the perfect shades for Tron, and the consistent, unbroken light source is perfect, and better looking than LED's. Also it stays cool, which is nice for anything you're gonna wear on your body, and it's flexible, so it can easily be sewn into any costume.

Also, EL wire is just a lot of fun for anyone who's into DIY stuff!

There are a lot of good instructables on using EL wire too.

[cubeberg]

I am actually trying to go the LED strip route with my daughter's costume. I found a way to diffuse it with Batting (the kind you use for quilting) that smoothes out the light. I've read a lot about EL wire in Tron costumes on therpf.com. They have some great tron costume threads (one is over 100 pages).

[fkhalsa]

Cool! Good luck on your daughter's costume.

[Chirpoff]

That... (!(echoes)!) coolness! Awesome!!!

FLYNN LIVES!

[cubeberg]

Glad you like it! Thanks for your comment!

[Zodiac4722]

what kind of programmer do you use? You show it in Step 8 in the picture...and how fast kann you falsh your avr with it?

[cubeberg]

I use a USBASP programmer. You can find them on eBay for around $6-$7 USD if you don't mind waiting for it to ship from China - although mine came very quickly (about a week).

I also had to build a target board (http://www.evilmadscientist.com/article.php/avrtargetboards) which requires a socket, perfboard, headers and some wire. There are actually tons of tutorials on this site for AVR programming as well. Another excellent resource is avrfreaks.net.

The USBASP programmer flashes the chips pretty quick - I'd say under 30 seconds. A much larger program would probably take longer, but it's fast enough I didn't even think about speed.

[jberg10]

I think nerds are hot, will you go out with me? ;-)

[cubeberg]

I'm pretty sure my wife might have a problem with that!

[jberg10]

Nah, your wife says its cool. :-)

[RapidPrototype]

You may wish to look at Thor's Webpage http://goo.gl/G6bYS his disk mod tutorial is quite detailed and expands on the work done by the Harford Hackerspace Guys by using a Netduino Mini he also uses more led's and recharge circuit and li-po batteries.

[cubeberg]

Thanks for pointing that out - I actually ran across his Picasa album when I was doing my initial research, although I hadn't seen his blog.
One of the things I'd like to note is that he hasn't completed his project yet (or at least hasn't updated the blog to indicate he has), and says he's spent about $200 so far. Including $9 for the disc - I've probably spent under $40. That doesn't account for the components I was able to obtain as samples - but I was specifically going for inexpensive. Plus, if the disc runs out of power - it's simple enough to drop in a fresh set of AAA batteries.

[zack247]

it looks really awesome!
one thing i would do is sand the inside of the transparent rings (the part the LEDs shine on) and that might help diffuse the light a bit more.

but it still looks awesome, and the possibilities with each led being addressable are endless!

maybe a version with rainbow colors just because?

[cubeberg]

Thanks! I never considered sanding the inside of the ring. It's a very rubbery material, so it would probably take some work to rough up - but a Dremel could probably do the trick.
I wish there was individual brightness control as well. There are other Maxim chips that support this, but they only come in QSOP packages.

I agree - an RGB version would be awesome!