A simple blink program on Arduino Leonardo: #include <Arduino.h> #include <avr/power.h> void setup() { // clock_prescale_set(clock_div_16); pinMode(LED_BUILTIN, OUTPUT); } void loop() { digitalWrite(LED_BUILTIN, HIGH); delay(1000); digitalWrite(LED_BUILTIN, LOW); delay(1000); } runs …

[image] pauljurczak: runs fine with default platform.ini file, but when I change CPU frequency to: [env:leonardo] platform = atmelavr board = leonardo framework = arduino board_build.f_cpu = 8000000L LED blinks twice as fast. When I uncomment clock_prescale_set(clock_div_16); it blinks 8 times…

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Setting CPU clock on Arduino Leonardo makes timing functions inaccurate

normandunbar January 22, 2022, 1:06pm 6

I’ve opened a new topic on this matter of the documentation giving the impression that the boards clock frequency can be changed using this setting, it’s at Documentation Bug?, if you are interested.

Cheers,
Norm.