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Delay Calculation

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I have a Stellaris Launchpad LM4F120XL, I am having troubles calculating delays. I set the System Clock to 20MHz with the following code "SysCtlClockSet(SYSCTL_SYSDIV_10 | SYSCTL_USE_PLL | SYSCTL_XTAL_16MHZ | SYSCTL_OSC_MAIN);". Now I want a 1 second delay, what is the formula I use to be able to calculate the correct number to pass as a parameter to the SysCtlDelay() function so it can give me a 1 seccond delay.


Thank You

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Well, if the delay loop takes 3 cycles, then 

1 second * 20 M Cycles/second / 3 cycles/loop ~= 6,666,667 


(Of course using a timer might be more accurate (maybe, if one cares), more elegant, allow the processor to do something else, or just more power efficient if go to sleep.)

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