Thanks for the response. Is there a way to use the MPXV415V vacuum sensor with the Grove Pi+(http://www.nxp.com/files/sensors/doc/data_sheet/MPXV4115V.pdf)? It returns a voltage and have tried to read as if the sensor is a potentiometer, but with no luck.
I would rather not abandon the Grove Pi+, but unless I can get readings from this analog sensor, I think I will ditch the Grove Pi+ and just code without it. If that's the case, can I use the Grove sensors (DHT22, button, light sensor, LED display, and a relay, directly to the GPIO on the RP3? Thanks for your assistance.