If you want to change the default IP address or WiFi settings:
Flash the via OpenWrt’s “System → Backup / Flash Firmware” section. Use the factory.bin from TP-Link (not the user upgrade file) – rename it accordingly. tplink mr3420 v5 firmware
Whatever you choose, and never interrupt a flash. Bookmark this guide for the next time you need to recover or upgrade. If you want to change the default IP
In OpenWrt/Padavan, you must install kmod-usb-net-cdc-ether and comgt to enable modem switching from storage to serial/network mode. tplink mr3420 v5 firmware