Vibrato(FM) effect on DE2

Thanks thepancake, my main problem was that i was writing and reading from address pointer based on mod signal. now when i am writing sequentialy from 0 to 720 and back fromo 0 to... It is working, and awfull noise from as you said discontinuities appears.

The thing is i realy don't know how to interpolate it. you know, this should be only small delay, so 720 is max delay. When accumulating address on every lrck i get 720 very fast. And modulation wave will is to slow if you know whan i mean :) Another problem.... Whole life full of problems :/