What is it?

Odiin is a NFC Tag Emulation toolkit! It's designed to be a straight forward, easy to use tool for emulating NFC-A tags of various types. In this current prototype stage, it's got partial implementations for several NFC Type 2 Tag types, including support for NTAG21X series tags, rudimentary support for MIFARE Classic and MIFARE Ultralight C. More functionality support and tag types should be a matter of firmware in the future!

Why did you make it?

Odiin started off as a learning project as I explored the nRF52840 platform, and spent time learning about NFC as a whole. I quickly realized I enjoyed reading arbitrary data and wanted to create a device that could do that with a swanky display.

Additionally, it evolved as a tool when my wife and I realized we could use it to emulate our Amiibos, so we didn't have to pull them out of the bin every time we wanted to use them for our games.

What makes it special?

It's the only device out there that works quite like this. There's lots of high end NFC tools, like the wonderful (and far more expensive) Proxmark3, as well as a lot of "do it yourself" solutions designed to be used by Arduinos and the sort. What I'm building looks to strike a happy middle ground between the two in terms of features and price, while being usable enough that anyone looking to do some NFC testing, tinkering, or learning!

What does it do?

It emulates NFC Tags! If you'd like to see it in action check out the video at the bottom of this page, or on YouTube!

Here's a truncated matrix of a few of the implemented and planned features:

Handling writes and saving is on the roadmap for sure, but reading has been the most useful so far. You might want to check the GitHub, in case this feature list is out of date!

How do I use it?

You simply need to attach Odiin to your PC via the USB cable, and after a short bit, you'll see a new drive pop up. That drive is exposing the SD card inserted into Odiin. You can drop files right onto it from there. You of course could put files on the SD card by using a regular SD card reader too!

Then unplug Odiin from your computer, select and load one of your files, and that's it! The LED turns blue to let you know the NFC tag is active! Tap the bottom of Odiin on your reader (be it a phone, PN532, etc...) and Odiin will serve up the data!

Right now Odiin works with raw binary files and serves them up as if it were the memory of the NFC Tag itself. In the future I hope to create software to help generate files, as well as to be able to generate them on the fly from the device, but that's all for a future firmware revision.

What else do I need to know?

This is absolutely a prototype. The firmware itself is not by any means finished, and there's very likely a fair amount of bugs. I'm getting these out there now, because it's difficult to know what the end-game toolkit would look like and do without feedback from folx! Odiin is open source! You're more than able to hack on the firmware yourself, or submit a pull or feature request for something you'd like to see it do!

Hackability

If you dream of more than the NFC tool, and want to twist Odiin to do more things for you, this puppy has got a lot under the hood that you can do a lot with:

• Based on the nRF52840 SoC, so which means not only NFCT, but also Bluetooth, BLE/mesh/thread/zigbee, and Nordic's 2.4GHz "proprietary" wireless communications. It's an ARM Cortex-M4F based chip with 1MB of flash, 256KB of RAM, and a single precision floating point unit!
• An on-board 8MB QSPI Flash
• ILI9341-driven 320x240 SPI LCD
• A (currently unused in the firmware) ATWINC1500 for Wi-Fi (802.11 b/g/n)
• The lovely WS2812B RGB LED, in addition to another discrete RGB LED (that's just hidden under the case!)
• A 5-way navigation switch, as well as the two additional push-buttons. Also hidden in the internals are 2 more buttons, one of which being a reset button.
• USB C (2.0) device connectivity
• LiPo Battery Charging

There's a lot of goodness to tinker and add all sorts of things to this device!

Why's it so expensive? I could build one myself cheaper!

That's the spirit! The hardware designs are also included in the GitHub repository! I've also included a bill of materials for where I sourced all my parts. If you're capable and not afraid of a little SMD soldering, go to town and let me know how your build goes!

The current price is based on my time and effort actually sourcing and hand building Odiin. In it's prototype phase, I'm doing things in very small quantities which doesn't do nicely when it comes to quantity discounts.

What does it come with?

You get the following:

• Odiin — obviously!
• USB C to USB A cable — for connecting to your PC, as well as charging
• 500mAh Rechargeable LiPo battery
• Micro SD Card & SD Card adapter — Sizes and variations depend on what I've got in stock, but should be at least 4 GB in storage
• Optional (pictured): 3D Printed Case & Navigation Nub — I'm currently printing these on a Formlabs Form 2 with the Tough 1500 resin
• My overwhelming thanks — this one is not optional, without you: my project wouldn't even be possible!