TIDUF34 july 2023
The messages sent to the MQTT broker can be received by any machine allowed to connect to the broker and subscribe to the message. Using Linux on the machine running the broker is done with mosquitto_sub -h 127.0.0.1 -v -t 'adc1raw' . This command shows all raw samples of the first ADC channel, as this is transmitted as topic adc1raw. The output on command line is shown in Figure 4-3.
A improved view can be achieved by using Node-RED as shown in Figure 4-4 by creating a flow to display the samples. Also this can be used to visualize the results of the FFT, transmitted in the adc1fft topic.