NFC

93 Articles

Reading The Chip In Your Passport

June 28, 2025 by 39 Comments

For over a decade, most passports have contained an NFC chip that holds a set of electronically readable data about the document and its holder. This has resulted in a much quicker passage through some borders as automatic barriers can replace human officials, but at the same time, it adds an opaque layer to the process. Just what data is on your passport, and can you read it for yourself? [Terence Eden] wanted to find out.

The write-up explains what’s on the passport and how to access it. Surprisingly, it’s a straightforward process, unlike, for example, the NFC on a bank card. Security against drive-by scanning is provided by the key being printed on the passport, requiring the passport to be physically opened.

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Plenty Of LEDs And Useful Too: The 2025 DORS/CLUC Badge

June 1, 2025 by 2 Comments

It’s always nice to see new developments in the world of electronic badges, and while there are events and badge teams pushing the technological envelope there’s still plenty of scope for innovation without too many exotic parts. This year’s DORS/CLUC open source conference in Croatia has just such a badge, with a large alphanumeric LED display as well as USB and an NFC reader. During the conference it displayed the user’s name and could be used in an NFC-based game, but it’s also designed to be used as a general purpose notification device afterwards.

The write-up is familiar to anyone who has been involved with badge production, a tale of long soldering sessions as missing components had to be added later, and of last minute firmware flashing. The heart of the machine is an STM32L073, with an IS31FL3731 LED matrix driver chip and an ST25R3916 for the NFC. All the files can be found in a GitLab repo, and there’s a video below the break showing it all in action.

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C64 on desk with NFC TeensyROM and game token

TeensyROM NFC Game Loading On The C64

May 23, 2025 by 6 Comments

When retro computing nostalgia meets modern wireless wizardry, you get a near-magical tap-to-load experience. It’ll turn your Commodore 64 into a console-like system, complete with physical game cards. Inspired by TapTo for MiSTer, this latest hack brings NFC magic to real hardware using the TeensyROM. It’s been out there for a while, but it might not have caught your attention as of yet. Developed by [Sensorium] and showcased by YouTuber [StatMat], this project is a tactile, techie love letter to the past.

At the heart of it is the TeensyROM cartridge, which – thanks to some clever firmware modding – now supports reading NFC tags. These are writable NTag215 cards storing the path to game files on the Teensy’s SD card. Tap a tag to the NFC reader, and the TeensyROM boots your game. No need to fumble with LOAD “*”,8,1. That’s not only cool, it’s convenient – especially for retro demo setups.

What truly sets this apart is the reintroduction of physical tokens. Each game lives on its own custom-designed card, styled after PC Engine HuCards or printed with holographic vinyl. It’s a tangible, collectible gimmick that echoes the golden days of floppies and cartridges – but with 2020s tech underneath. Watch it here.

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A Music Box Commanded By NFC Tags

March 31, 2025 by 7 Comments

[Luca Dentella] recently encountered a toy, which was programmed to read different stories aloud based on the figurine placed on top. It inspired him to build an audio device using the same concept, only with music instead of children’s stories.

The NFC Music Player very much does what it says on the tin. Present it with an NFC card, and it will play the relevant music in turn. An ESP32 WROOM-32E lives at the heart of the build, which is hooked up over I2S with a MAX98357A Class D amplifier for audio output. There’s also an SD card slot for storing all the necessary MP3s, and a PN532 NFC reader for reading the flash cards that activate the various songs. Everything is laced up inside a simple 3D-printed enclosure with a 3-watt full range speaker pumping out the tunes.

It’s an easy build, and a fun one at that—there’s something satisfying about tossing a flash card at a box to trigger a song. Files are on Github for the curious. We’ve featured similar projects before, like the Yaydio—a fun NFC music player for kids. Video after the break.

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Yaydio, A Music Player For Kids

March 29, 2025 by 6 Comments

Music consumption has followed a trend over the last decade or more of abandoning physical media for online or streaming alternatives. This can present a problem for young children however, for whom a simpler physical interface may be an easier way to play those tunes. Maintaining a library of CDs is not entirely convenient either, so [JakesMD] has created the Yaydio. It’s a music player for kids, that plays music when a card is inserted in its slot.

As you might expect, the cards themselves do not contain the music. Instead they are NFC cards, and the player starts the corresponding album from its SD card when one is detected. The hardware is simple enough, an Arduino Nano with modules for MP3 playback, NFC reading, seven segment display, and rotary encoder. The whole thing lives in a kid-friendly 3D printed case.

Some thought has been given to easily adding albums and assigning cards to them, making it easy to keep up with the youngster’s tastes. This isn’t the first such kid-friendly music player we’ve seen, but it’s certainly pretty neat.

Close up of a Sony FX-300 'Jackal' radio

Packing Even More Features Into A Classic Radio

January 17, 2025 by 11 Comments

When it comes to hacking niches, breathing new life into vintage devices is always an exciting challenge. [t0mg]’s recent project exemplifies this with his 1978 Sony FX-300 ‘Jackal’ radio. He’d already upgraded the radio in 2021 and turned it into a feature-packed marvel, but there’s always room for improvement.

[t0mg]’s initial 2021 build had its quirks: noisy sound, a subpar display, and a non-functional radio module. Determined to enhance these aspects, he sourced an IPS version of the original 3.2″ ILI9431 LCD, significantly improving viewing angles. To tackle the audio issues, he integrated an M5Stack Atom microcontroller, utilizing its Bluetooth A2DP capabilities to deliver cleaner digital sound via I2S to the Teensy audio board. The Teensy itself got a complete wire overhaul just for the sake of good craftmanship.

The new setup also enabled the display of song metadata. Additionally, [t0mg] incorporated a dedicated Arduino Nano clone to manage inputs, streamlining the overall design. The revamped ‘Jackal’ now boasts a bunch of impressive features such as displaying RDS data for FM stations, voice recording, and an NFC reader for personalized playlists.

If you’re into radio makeovers, look into this post for a real golden oldie, or start out with the basics. For [t0mg]’s earlier improved version of this Jackal, read our article on it here.

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ATTiny NFC Thermometer keychain with keys

Tiny NFC-Powered Keychain Thermometer

December 8, 2024 by 9 Comments

What if your keychain could tell you the temperature, all while staying battery-free? That’s the essence of this innovative keychain ‘NFC_temp’ by [bjorn]. This nifty gadget harnesses energy from an NFC field—like the one created by your smartphone—to power itself just long enough to take a precise temperature reading. Using components like an ATTiny1626 microcontroller, a TMP117 thermometer, and an RF430CL330H NFC IC, NFC_temp cleverly stores harvested power in a capacitor to function autonomously.

The most impressive part? This palm-sized device (18×40 mm) uses a self-designed 13.56 MHz antenna to draw energy from NFC readers. The temperature is then displayed on the reader, with an impressive accuracy of ±0.1 °C. Creator [bjorn] even shared challenges, like switching from an analog sensor due to voltage instability, which ultimately led to his choice of the TMP117. Android phones work best with the tag, while iOS devices require a bit more angling for reliable detection.

Projects like NFC_temp underscore the creativity within open source. It’s a brilliant nod to the future of passive, wireless, energy-efficient designs. Since many of us will all be spending a lot of time around the Christmas tree this month, why not fit it in a bauble?