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Altera_Forum
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15 years ago

Help me about measure clock on osciloscope.

Hi everyone, I have project on board DE2. I use PLL in megafunction to create the clock 500MHz from 50MHz. Then i use clock counter to decrease the clock from 500MHz to clock_out 250KHz, 125KHz, 6...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

I understand, i used pll with inclk0 = 50MHz and 2 output clock that 500, 400MHz. Can u tell me why i can not create the second output clock 400MHz??? it said that :

"Cannot implement the request PLL".

"Cause : Request mult/div factor not achievable".

And the output clock parameter : mul = 20 , div = 3 why???(50*20/3 != 400MHz)

if right , they must be mul = 8, div = 1 because 50MHz * 8 = 400.