HCHO + RaspberryPi
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Yes, yes, i think im not first with that question, but anyway how to do that correct? Because NO any information how to connect this - Formaldehyde (HCHO) Sensor(SKU:SEN0231) to the raspberry pi(in my case pi 4b). The description says: The Formaldehyde (HCHO) sensor is an Arduino & Raspberry PI compatible module, but any information how to connect and configure this on raspberry. So i bought this - IO Expansion HAT for Raspberry Pi 4B/3B+(SKU:DFR0566) and try to connect your HCHO sensor with my raspberry and... i really dont have any idea how to do that...sensor have 3 pin connector ("-" if I got it right its GND , "+" - VCC and S - Signal - DAC or UART), but OK, onboard IO Expansion HAT for Raspberry we have 4 pin UART connection: "+", "-", TXD and RXD, so how to do that right, or that sensor not compatible to this?? And even if i connected that with raspberry, how to configure it and sensor became usefull? Sorry if my question sounds like stupid - english not my native language.