how to generete a pulse after a zero crossing detect in dynamic data with a phase delay.

Hi I´m acquiring a 60 Hz sinusoidal signal from NI USB-6363 in LabVIEW, so then i want to produce a pulse after a zero crossing in each semi-cycle with a phase delay with the NI USB-6363, for example Labview detects a zero cross and 120° after of the crossing i want to produce a pulse with a rising time of 50us. The phase delay needs to be controlled.

P.S. The acquiring block that I´m using produces Dynamic Data