Modelsim: Unknown State

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In the modelsim simulation, there is a signal, delay1, shows its value and undefined state(red colour) periodically. It shouldn't show unknown state based on my code. I wonder why. Pls have a look on my code attached.

thanks

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Hi,

I run your design with modelsim and I can confirm your problem. What I'm wondering

about is that I could not find the signals q1 and q2 in the Waveforms. Maybe I missed something.

I also setup a Quartus project and generate a netlist for simulation. With the netlist the unknow is gone. Maybe you can try it by yourself ?

Kind regards

GPK