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Hi,
I see that the different crystal frequencies are almost all the same price.
I have read many threads or specs that suggested the use of a higher crystal frequency to make everything more stable or more accurate.
Is there any advantage in selecting a 4 MHz over a 20 MHz?
Shouldn't I just select the highest crystal frequency supported by the PIC I am using?
Thanks to anyone for clearing this out.
Mike
I am not so sure about that... Not sure that it make a difference in that respect.Quote:
I have read many threads or specs that suggested the use of a higher crystal frequency to make everything more stable or more accurate.
Advantage of a low frequency would be the chip can be ran at a lower voltage. Interfacing with low voltage peripherals and battery supplied gadgets this is handy.
If you are using software serial and the baud is 9600 or higher you need a faster OSC.
Different PWM resolutions are scaled with different OSC speeds.
Timers / interrupts. The OSC speed will/maybe make a difference on how you code.
So it pretty much depends on the overall project. Just like deciding on any other part.
Do you have something specific in mind or just a general question?
It was mainly a general question.
So what makes the difference is power consumption?
If power is not an issue then I could use the fastest crystal supported by the PIC and it wouldn't cause an issue?
In general yes.Quote:
Originally Posted by lilimike
A chip running a 4Mhz will have a different resolution for the commands than say a 20MHz:
COUNT
PULSIN
PULSOUT
PWM
and maybe others I am not thinking about. So if you need a wider resolution then a slower OSC will be needed.
But in general, crank it up!!! :D It does not hurt the chip.
Got it!
Thank you Dave
Mike