internal clock

[Bilal]

hi.. i am using pic16F877a how can i generate internal clock..
i want to know what short comes can be faced with internal clock generation..
thanks
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[Ttelmah]

You can't.
Read the chip's data sheet. Any mention of an internal RC oscillator?.

To use the internal oscillator, you need to select a chip that has one...

Best Wishes

[SherpaDoug]

If you do use a chip with an internal oscillator be sure to read the datasheet about oscillator accuracy over voltage and temperature changes. Usually they are not quite good enough for serial comms over all conditions.
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