The YX850 Power Failure Automatic Switching Standby Battery Lithium Battery Module DC5V-48V Emergency Converter. It is an automatic switching module. When the battery is dead or there is a problem with the battery, it is powered by the power supply.
The ENC28J60-I/SO is a standalone Ethernet controller with an industry standard Serial Peripheral Interface (SPI™). It is designed to serve as an Ethernet network interface for any microcontroller equipped with SPI Communication.