what cap and restier to use for 4mhz clock speed
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what cap and restier to use for 4mhz clock speed
I referred to this site:
http://www.piclist.com/techref/microchip/osc.htm
I don't recall what I ended up using, but can post it later.
The most common configuration for a 4Mhz crystal is 22pF caps and no resistor.
*edit* Just realized he is prob talking about an RC oscillator. In that case, C=15pF R=15k will give you 4.4Mhz. If you need to 4.0Mhz, you can use C=10pF R=25k (you will have to use a combination of 2 resistors to get this value). One thing to keep in mind tho, caps and resistors have tolerances which mean its VERY difficult to get accurate timing with RC oscillators. If your project does anything time dependant, i'd recommend a crystal.