hi,
I would like to see if it is possible to make the Arduino talk to the Withings blood pressure measurement cuff. Specifically the Bluetooth enabled version since this would provide the cleanest integration with the device. As far as I can tell, Withings have not published any information on how to talk directly to the cuff (over bluetooth).
I did send them a request for this information today, but to be quite honest I am not expecting much of a response. It would be very impressive if they did though. (I can't really see what advantage they'd gain by not publishing this information, really).
Has anyone else tried to talk to the Withings BP cuff over bluetooth?
How about reverse engineering the protocol? I have no experience trying to intercept or analyze bluetooth traffic. Are there any tools that might be helpful in this respect? For instance is there any hardware that would allow me to proxy traffic between my iPhone and the cuff so I can look at the traffic that goes over the BT link? Or are there simpler solutions that will just let me eavesdrop on the traffic? (As you might understand: I don't even know if it is encrypted. Is it? :))
(Of course, it might be that the cuff is just a primitive sensor device and that I will have to implement the measurement logic myself. Does anyone know if the cuff has the sphygmomanometer measurement logic onboard, or if this is implemented in the smartphone app?).
-Bjørn