I am currently using dsPIC33EV256GM106 and trying to experiment with the performance with and without PLL. My XTAL is 8MHz. I was trying with primary clock as well as FRC mode to compare the performance. I used the reference code from this link https://ww1.microchip.com/downloads/en/DeviceDoc/70005131a.pdf ( example 7-1 and 7-2). To my surprise with PLL (in FRC mode), the timing performance is worst. I am trying to toggle a port based on delay. What is the problem?
Timing
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without PLL --output toggles in 44us
with PLL based on the code below--output toggles at 290 us
But with primary clock timing is same with or without PLL as 44us.