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Sensor - RFID USB Sensor

SparkFun RFID USB Reader

What is an RFID Sensor?

An RFID sensor stands for a Radio-frequency identification sensor. The RFID works by emitting electromagnetic waves, essentially waiting for a tag compatible with the RFID network to come within its vicinity, and then proceeds to receive the signal and convert it into data that's being used. This data could allow a door to unlock, for example, as we see in our everyday life while attending NYU.

Other applications of this sensor could be things such as inventory management, asset tracking, personnel tracking, controlling access to certain areas, ID badging, supply chain management, and theft protection (used in convenience stores to prevent someone from stealing a product).

Some potential ideas for a project:

• Monitoring use of supplies in the IMA/ITP shop after hours
• Tracking the movement of someone during the day
  • It might be interesting to view someone's habits throughout the day working from home—the RFID could track if they get up and pace, where they go, if/how many times they get up to go to the kitchen/bathroom, do they move to different locations of their home, etc.
• Lock/unlock access to your computer using an RFID tag
• A lamp that turns on/off from the tap of the RFID tag

Datasheet

The RFID Sensor (The actual sensor itself) is the black square sitting on top of the breakout board. The sensor, ID12-LA, has 11 pins for connection. I was surprised to learn that the sensor has only 2 pins that are transmitting the card reading data. The rest is the connection to control the chip.

This is even more fun when I realized that this RFID chip could be used to measure magnetic force!

The RFID chip is outputting data in ASCII format. We learned that the last set of letters/numbers is generated as a sum of all the binary code combined.

Trying The RFID Out

Get off on the wrong foot

We tried to follow the tutorial on Sparkfun for using the RFID USB sensor. The sensor itself is from Sparkfun. We head directly into the problem at the very beginning. The RFID USB sensor needs FTDI drivers to work directly over the USB. It turns out that the driver for macOS 11 is still in beta. Similarly, when the sensor is connected to the laptop, it just won't send any serial output. We tried to swap out the cable, sensor, laptop, and RFID cards one by one. It just won't show up in the serial monitor. We have to give up on this sensor at the end.

Trying with a different type of RFID

The other more common RFID tag sensor is MFRC522. We decided to give it a try. Unlike the previous one, this sensor is built-in with the antenna and it runs on SPI protocol. Aidan has been amazing at helping us set up the MFRC522 with a video tutorial.

We ran into a small issue when the sensor couldn't receive any data from the keyfob. This was quickly resolved after our friend Angelo's advice. He pointed out that the breadboard we were using might not be working properly. We swap out the breadboard and it works! Aidan keeps following the tutorial and we end up having a security alarm system with a buzzer and LEDs!