Atmega 328PU reset pin and clock requirements and use.

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Joined Sep 30, 2017
I am planning to build my own controller board using a 328 MCU. Is there any requirement for the reset pin to be attached? I am reading that the pin can be reconfigured for GPIO which indicates that it is not always required. My program never calls for a reset but will (when I learn to) involve power down mode and wake on serial.

Also about using the internal clock (again when I've learned) I am reading that it can be unreliable with the serial communication (baud timing) given that it has 20% accuracy. But I've read at other posts that whilst not as accurate as an external crystal, its accuracy is largely overstated for a typical application, so for example i would like to use a gsm module for sending data when requested, what would the difference using the internal clock at 1MHz or 8MHz to a regular 16MHz external clock? is timing really that important for such functions

sorry im in the wrong forum


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