The TCM 515 Clickboard EnOcean 3 click carries a TCM 515 transceiver, which is a bidirectional gateway for EnOcean’s 868 MHz radio systems. It includes an on-board PCB antenna for transmission and reception of radio telegrams. The TCM 515 Clickboard is designed to run on a 3.3V power supply. It communicates with the target MCU through UART (TX, RX pins), with additional functionality provided by RST and EN pins.