Only 0 outputs in waveform simulation - Only 0 outputs in waveform simulation I have a problem with simulating schematics in Quartus II 13.1 Web Edition. I've tried to simulate several projects, but every simulation gives me 0s in the outputs. I remember that I accidentally changed something in the schematic of a specific block, but I don't know exactly what. I'm not sure if that is the problem, but reinstalling doesn't work. Replies: Re: Only 0 outputs in waveform simulation Hi, circuit behaviour is just as expected. You have a quad DFF 74175 connected as circular shift register. All register are initially cleared, shifting "0000" will never result in a nonzero bit. Replies: Re: Only 0 outputs in waveform simulation Hi, Possible to provide the design file for better tracking down the problem? Thanks, Sheng