External I2C Baro - how do I check its being used?

I think the title says it all! The long version: I added an external I2C connected barometer - one of these: http://www.ebay.co.uk/itm/141799881200?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT
and in the hope its being detected I have set GND_PRIMARY=1
…but how do I know that this is a) being detected, and b) being used by Plane?

I have the same problem!

Could you find a solution?

Not yet!
*(sorry, it forces me to write 20 chars minimum :slight_smile: