ATTiny85 clock speed?
i have sketch:
digitalwrite(led_pin,1);
delay(100);
digitalwrite(led_pin,0);
i'have uploaded same sketch on same tiny different clock speed, , realized higher clock speed - higher real delay.
1mhz - fastest (minimal delay)
16mhz - slowest ( delay(100) led lit 2 sec)
am missing something? thought higher clock speed delay might shorter, not longer. why?
digitalwrite(led_pin,1);
delay(100);
digitalwrite(led_pin,0);
i'have uploaded same sketch on same tiny different clock speed, , realized higher clock speed - higher real delay.
1mhz - fastest (minimal delay)
16mhz - slowest ( delay(100) led lit 2 sec)
am missing something? thought higher clock speed delay might shorter, not longer. why?
hi maia
it because attiny85 running @ default 1mhz clock ship factory.
when clock speed on target board specify in arduino ide matched, delay accurate. so attiny85 running @ 1mhz runs slower expected when sketch compiled 16mhz target loaded because clock using slower code internally expects.
to change clock, select 16mhz target , use 'burn bootloader' option in arduino ide. this set internal fuses in microcontroller. then use clock speed target uploading program , work advertised.
use 8mhz code on 1mhz pocessor 100ms delay becomes 800ms. use 16mhz code on 1mhz microcontroller , 100ms becomes 1.6seconds. that's you're seeing.
hope helps,
geoff
it because attiny85 running @ default 1mhz clock ship factory.
when clock speed on target board specify in arduino ide matched, delay accurate. so attiny85 running @ 1mhz runs slower expected when sketch compiled 16mhz target loaded because clock using slower code internally expects.
to change clock, select 16mhz target , use 'burn bootloader' option in arduino ide. this set internal fuses in microcontroller. then use clock speed target uploading program , work advertised.
use 8mhz code on 1mhz pocessor 100ms delay becomes 800ms. use 16mhz code on 1mhz microcontroller , 100ms becomes 1.6seconds. that's you're seeing.
hope helps,
geoff
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