Calling Card: RFID Texting

Introduction: Calling Card: RFID Texting

About: An engineer, seamstress, cook, coder, and overall maker. Spent a summer at Instructables; got a degree in E: Neural Engineering at Olin College; made a microcontroller (; now thinking about climate...

This is a tutorial for making a device that can receive an RFID card tap (like your transit card– Clipper, Orca, CharlieCard, etc.), read that card's unique identifier, and send that information over the internet, through Twilio, to a text on any phone.

Use Cases:

  • "I'm home" text to family members
  • Someone came to visit, but you weren't there (think Victorian calling cards)
  • Very fast check-ins at locations with associated RFID cards (e.g. if you could register a transit card with Foursquare to check in at locations)
  • Tool checkout– tap to text someone that you're borrowing their thing

This instructable uses code, but you don't actually need to know how to program in order to copy my project. The only technically difficult part of this is using the command line– but you can learn the basics of that in about a minute here: Command Line 101 for Windows || Command Line 101 for Mac

Calling Card

Tap an RFID card on a Tessel RFID reader to send a text over Twilio to any phone.

You need

  • Tessel + RFID Module + RFID card (one comes with the module)
  • A phone (to receive texts)

Setting up

  1. Set up your Twilio account (it's free!)
  2. Install your Tessel
  3. Clone this repo by typing `git clone` in the command line/terminal
  4. Set up your config.json file based on the example-config.json file
  5. Run `npm install` in the terminal to install Node dependencies
  6. Connect Tessel to the internet
  7. Run the code on Tessel: `tessel run index.js` in the terminal
  8. When the console logs that the reader is ready, tap a card to receive a text!

Future work

This is a work in progress; it would be much more useful to create a lookup for different UIDs, and associate specific RFID cards with specific people. I'm working on it.

See the writeup and find the code here as well.

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