Hi all,
I am using quartus 2 9.1 sp2. I want to run an ALTPLL considering only one input (Clk) and two output ( c0 and locked output). I have generated the vhdl file for modelsim. I simulate it with 50MHz clock and i see no output on both the output signals. Please see the files below for .bdf and modelsim screenshot. Please help me how to see the output and what changes i need to make. Thank you Ash連結已複製
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Hi amod,
Two things: you only show 5-6 ns on your waveforms, the PLL models, like real PLLs, take some time to initialize and sync before you get an output. 6ns is not nearly enough time. I forget how long this takes in simulation (I think it's a lot less than for the real devices) but give it a us or so before you give up. Second, it looks like the clock you're feeding it is NOT 50MHz, but 10GHz! The period shown is 0.1ns, check your clock generation. -FredAre you getting any warning when you run modelsim? Perhaps a library is not set up. See this thread: http://www.alteraforum.com/forum/showthread.php?t=21634
A testbench is simply a verilog or vhdl script where you set up you input signals to the system that you are simulating. Usually, you would write one by hand.
How did you set up the input clock signal to your pll system?