UART Remote Comms

Has anybody any experience of wireless remote UART comms with Nextion. I have a successful project that places HC-12 433Mhz modules between the MCU (ESP32) and the Nextion Enhanced (3.5). The MCU simply passes standard serial strigs through Serial2 and the Nextion passes 4 byte HEX as per all the excellent tutorials available. This works brilliantly indicating :

//Data Format: <#> All in hex. #=23, len=02, P=50 (W=57), ID
printh 23 02 50 08

As the range of the HC-12 is very limited I have started to investigate LoRa in the form of E220-400T30D but am experiencing a problem. The MCU data is readily received at the remote Nextion but I am unable to send the necessary data to the MCU (new page trigger for example). I get nothing at the MCU against any screen triggers on the serial monitor.

If anybody has any experience of the E220 that would be greatly appreciated. I am assuming this wraps the HEX up in it’s own header (Chan number, key etc) but I’m struggling to identify what the issue is as in my simple little mind I would ultimately expect it to act as the HC-12 does.

Did you check if the modules work correctly without other hardware connected?

You may test for example with two terminal programs on the same PC and with two RS-232 ports to see if the modules talk to each other.


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