A while ago I received a couple of I/O port expander modules that use the I 2 C protocol. Using that Chinese module, you can use only the SDA and SCL pins of your Arduino, or any microcontroller ...
For starters, you need a pre-wired NFC RFID module as the key hardware. NFC and RFID projects have become a huge trend, but many modules are pricey for electronics hobbyists and need a complex setup.
Some results have been hidden because they may be inaccessible to you
Show inaccessible results