HLK-RM04 Kits. HLK-RM04 Base Board. Nano Sheild. 1, a serial port turn WIFI module, a serial port turn Ethernet module, Ethernet switch WIFI multi-function WIFI module, a serial port server module, make it easy for your serial port device connected to the Internet, transparent two-way data transmission, to ensure the highest limit of ease of use and compatibility.
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