Yes, that's easy - the phase variable wraps at 1024, so every 1024 times through the loop() function is
one cycle of the waveform.
I put a 2ms delay in the loop, so it will take about 2.05s per cycle as written.
As I've noted above this loop() is purely to demonstrate the principle - you are free to update
u,v,w whenever you want [ guarded by noInterrupts()/interrupts() ]