@Nca78 said in Particle Powered Air Quality Sensor Logging to Google Docs: @Sebex said in Particle Powered Air Quality Sensor Logging to Google Docs: Perhaps I don't necessarily need to use the same pins Both the sensors you quote are using I2C. So they both use the same 2 pins (SDA, SCL) to communicate. You can put many I2C sensors on those same pins, they each have an address to know which sensor is receiving/sending data to the master (here, your arduino). Look for a tutorial on I2C first. Thanks I get it now :smile: