I'm working with Altera PLL/Altera PLL reconfig IP (Cyclone V).
The input to Altera PLL is 160 MHz ,the outputs are 125 MHz each with difference of 225 degrees .
Then I want to change both outputs to some another value: for example 120 MHz each. I can change value of M-counters, N-counters and C-Counters accordingly , but how can I choose two C-Counters simultaneously?
In addition I've received strange results in the simulation:
1). At the first reconfiguration both outputs are 125 MHz.
2).At the second reconfiguration first output is 20 MHz (according to M,N,C counters), but second output is 53.333 MHz -despite the fact , that only first counter was chosen.
Did you get chance to do the simulation ? Ideally it shouldn't ..if your setting and counters values are correct..then you should get expected values for the both the output of the PLL.
Thank you ,
In order to check how Fractional N-PLL reconfiguration works at simulation , I've generated new project .
The project consists of PLL, RECONFIG_PLL and incoming/outcoming signals. PLL receives 160 MHz at its input and has only one output .
The initial output is 128 MHz, and then changes according to incoming data.
when I've used Fractional N-PLL, then simulation has stuck and stopped after 5000 iterations.
when I've used Integer N=PLL, then simulation works properly.
The TB is same for both N-PLL.
I'm working with ModelSim 10.5 Starter edition.
Why simulation of the Fractional N-PLL is sticking?