Articles tagged with “mpr121”

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 And, unfortunately, the biometrics part is covered by NDA and can not be published.

MPR121 is a Proximity Capacitive Touch Sensor Controller developed by the company NXP. Being only 3x3 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.