lesept:
This one must be OK
The direction of the wave is good but the diodes must light up from: 7 to: 0. In this code they light up from: 8 to: 1. After giving the mass on the pin: 4, the wave performs one full cycle and goes out it should shine to the moment of holding the mass. And go out after subtracting the mass. Correct it and it will be fine 