Hi, I have uploaded optiboot bootloader to my nano via ISP. My arduino IDE detects the board as optiboot 8MHz.Also I have selected the optiboot on 32 pin cpu (I have a 328p-au) in the ide.Ok. But millis() is not accurate (my 1min counter (at 16mhz), only count 48.5sec in order a min when running …

How to setup Arduino to 8mhz properly?

noiasca September 13, 2021, 4:45pm 7

install the MiniCore Boards.
burn a bootloader with internal 8Mhz

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