Thanks for your quick answer.
Perhaps my explanations were not sufficients.
Device and software run well in case of APBM use (24 hours observation).
But then :
I delete all datas.
I mesure my blood pressure three times (so there is 3 mesures in the device memory)(I see them)
I connect the PC to the device
I try to dowload datas from device to PC, but software tell me : "no data recieved, COM closed"
That seems not a normal running.
Is there something to do ?