ECIO-40 clock speed

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ECIO-40 clock speed

Postby GRAEFFLY RAPHAEL » Tue Aug 27, 2013 6:42 am


I am using ECIO-40 in my project, but in the window clock speed, i could not change the speed (default : 4800000 Hz) but the crystal on my ecio board is a 4000000 Hz, therefore the timings are not respected on my code (timer division, prescaler ....) ??

thank you

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Re: ECIO-40 clock speed

Postby medelec35 » Tue Aug 27, 2013 7:50 am

The crystal should be 4000000 (4MHz)
The clock setting of ECIO-40 is 48000000 (48MHz)
Configuration file and clock settings are locked so not alterable by user.
ECIO-40 uses a 18F4455 which has a built-in PLL multiplier.
Which multiplies the 4MHz to 48MHz.
That is why you can't alter your clock speed from the correct 48MHz.
All timings should be correct.
If you have an issue with timings on your flowchart, then if not commercially sensitive can you post your flowchart please, then we can take a look at it for you.
Can you also post your C code that was generated after compiling, so we can check every thing is set as it should be.


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