Disable CLK Pre-scaler in AVR to use 8MHz Internal Oscilator

Just wanted to share this small piece of information that can help many . If you want to Run your AVR at 8MHz from the internal oscillator you need to disable the CLK/8 Fuse. You can do this by burning new fuse values. This can also be done in you main function as well. Below is a piece of code that will change the pre-scaler to zero.

// set the clock speed to "no pre-scaler" (8MHz with internal osc or
// full external speed)
// set the clock prescaler. First write CLKPCE to enable setting of clock the
// next four instructions.

Hope this will help!


Dost Muhammad Shah

Dost Muhammad specializing in Embedded Design, Firmware development, PCB designing , testing and prototyping. He enjoys sharing his experience with others .Get in touch with Dost on Twitter or via Contact form


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