While working on the side project URU Card [/tag/uru-card/] — the open-source authenticator device in the form-factor of a regular credit card — I have noticed that it is way more suitable for daily use. The device like this can be carried around simply in the wallet together with other credit cards. So, I have redesigned the URU Key in this format.
MPR121 is a Proximity Capacitive Touch Sensor Controller developed by the company NXP. Being only 3×3 millimeters in size this chip allows us to connect up to 12 touch sensors. The communication protocol is I2C. This makes it an ideal candidate for the user keyboard in the URU Card [/tag/uru-card/] project.
Recently I have received the new batch of PCBs for my URU Card [/29.06.2020/uru-card-arduino-fido2-authenticator/] device. Since I do not have a 3D printer and appropriate skills I am going to construct a hard shell using the stack of PCBs. This time I have chosen black colour for the boards as it comes in a nice matt finish.
About one year ago I have purchased a widely available fingerprint identification module with UART interface. You can find this module almost everywhere for quite a decent price. However, the information about how to use it with Arduino is not that easy to find. I am interested to use it with the URU Card [/29.06.2020/uru-card-arduino-fido2-authenticator/] device so I took some time to play with it.
It's quite a long time since the last update, but the summertime asks you to spend more time outside and I could not resist this call. Nevertheless, here's the small project I made.
This update was delayed due to summer holidays but it brings achievement of the very important milestone. Now we have a very minimal implementation of the FIDO2 authentication protocol on the Arduino framework. The simplicity of the Arduino platform and the availability of the hardware opens the door to secure authentication to everyone interested.
The components I am using in my projects are very small and have a strong tendency to be even smaller I have learned a new technology of soldering SMD components — using a special stencil.
After publishing the URU Key project people keep asking me to make it open source. I have tried to organize sources in a more readable way but I still think that plain C and ESP IDF are too difficult for the broad audience. And, unfortunately, the biometrics part is covered by NDA and can not be published.
