AVR-Chat

--- In AVR-Chat@yahoogroups.com, "aswinefy2003" <aswinefy2003@y...> 
wrote:
> Hai 
> I am using Atmega 16 with external clock It works fine with this  .I 
> found that the microcontroller is running even when there is no
> external  clock Please advice about this

Unless you have modified the fuses, the chip is set up to use the 
default clock source - a 1MHz internal oscillator as described in the 
datasheet.  The datasheet also gives the CKSEL settings that should be 
used for an external clock.

One thing to note is that if you intend to use in-system programming 
(ISP) and you program the fuses for external clock, you'll have to 
provide the external clock during programming.

Don
ZBasic Microcontrollers
http://www.zbasic.net