Getting data into Cayenne from the Raspberry Pi serial port usb?

I can get serial data on the terminal prompt using this command below.
read -n 2 LINE < /dev/ttyUSB0;echo $LINE

But I am unable to feed this data to Cayenne. I know I could just rewire a few things and use the GPIO but the Pi doesn’t really handle analog input. My guess is there is some-kind of MQTT that I can can’t find.

Thanks in advance

Unfortunately you can’t just send data to Cayenne yet, but they will be opening up the API to allow this. For now you can get an ADC that is supported: MCP3004, MCP3204, MCP3208, MCP3008, ADS1115, ADS1015