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Topic: AVR fuse bits factory setting (Read 742 times) previous topic - next topic

sreedevk

I just want to know a bit more about AVR fuse bits. I want to know about their default fuse setting. Considere a fresh Atmega8 chip manufactured out of an Atmel factory. Will the reset pin be working as an digital pin or by default will it be a reset pin? And will it be using the internal 8MHz clock by default or the external crystal.

Thanks

Jack Christensen

These questions are answered in the datasheet, but the reset pin is enabled and and the system clock is the internal RC oscillator running at 1MHz.
MCP79411/12 RTC ... "One Million Ohms" ATtiny kit ... available at http://www.tindie.com/stores/JChristensen/

Nick Gammon

It would be silly for them to be shipped with reset disabled. I agree with Jack.
http://www.gammon.com.au/electronics

ehrja


Will the reset pin be working as an digital pin or by default will it be a reset pin?


Nick with all the respect, I don't think sreedevk was referring to that. I guess it means if the reset pin could be used as digital pin normally, and how to do that.
I have the same question about the reset pin, because I has been playing around with an attiny13 and couldn't use the reset pin, as digital pin.

Erni

You can use the reset pin as analog input.

http://forum.arduino.cc/index.php?topic=87517.15

As far as I remember i managed to use it for voltage down to 0.5 x Vcc, before it was resetting, but I don't think the treshold is well defined.

Nick Gammon


Nick with all the respect, I don't think sreedevk was referring to that. I guess it means if the reset pin could be used as digital pin normally, and how to do that.


What was he referring to then? The ability to have the reset pin "not reset" gives you another digital/analog pin, at the cost of having to power off the device to reset it.
http://www.gammon.com.au/electronics

ralphd



Will the reset pin be working as an digital pin or by default will it be a reset pin?


Nick with all the respect, I don't think sreedevk was referring to that. I guess it means if the reset pin could be used as digital pin normally, and how to do that.
I have the same question about the reset pin, because I has been playing around with an attiny13 and couldn't use the reset pin, as digital pin.


You need to program the RSTDISBL fuse.  If you plan to program it again you'll need to have a bootloader on it (though not much flash will be left with only 1K to start with), or a high-voltage programmer.

Unthinking respect for authority is the greatest enemy of truth - Einstein.

ehrja

Oh I can see my problem now,  an apologize for speak with a doubt. Happy new year for all you.

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