Solved
GND diference
There are no diference for conect to gnd in the left side o right side?

There are no diference for conect to gnd in the left side o right side?

Correct, on the DISCO side they should be on the same plane.
On Arduino shields I'd be more circumspect, and check the continuity, especially proto-shields as they might not have copper/routing between pins of the same designation on either side of the board / connectors.
Enter your E-mail address. We'll send you an e-mail with instructions to reset your password.