This code ties together an ESP32 (TTGO T-Display) with an ENC28J60, Mosfet and serial board to create an 'All in one' network tool that supports displaying DHCP, CDP and LLDP information. It's all functional and working. For wiring schematic and other information: https://modlog.net/esp32-cdp-lldp-dhcp-third-edition/
ModLogNet/ESP_ENC_CDP
This is written for ESP32's and supports CDP, LLDP, and DHCP using an ENC28J60
C++