AVR-Chat

> Fuse setting are ok. But the problem is that my crystal frequency is not
> stable everytime. For example if i am using a crystal of 1.8432MHz with
> 22pf capacitor the output frequency is nearly 2.2 MHz, but when i replace
> the capacitor by 27pf the output frequency is nearly 1.9 Mhz. So Now i am
> cofused, how to choose capacitor so i get stable frequecy as per crystal.

  I think that you've answered your own question with your observations. 
A higher value cap gives greater stability.  The higher value tends to
slow the clock startup time, but in most cases I don't think that is an
issue.

DLC

> R.P.Modi
>
>
> ----- Original Message ----
> From: David Appleton <englsprogeny@yahoo.com>
> To: AVR-Chat@yahoogroups.com
> Sent: Tuesday, 15 April, 2008 5:21:06 PM
> Subject: [AVR-Chat] Re: Help for circuit design
>
>                 Check your fuse settings.
>
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-- 
Dennis Clark
TTT Enterprises