user72243: Is there any way to know the resolution of micros() for the Arduino Portenta H7. I have checked for other boards e.g. Nano which is mentioned as 4 uS. However, I couldn't find one for Portenta H7.
Is there any way to measure or look for that

user71575: The micros() language reference states that, "[The micros() function] returns the number of microseconds since the Arduino board began running the current program. This number will overflow (go back to zero), after approximately 70 minutes. On the boards from the Arduino Portenta family this function has a resolution of one microsecond on all cores. On 16 MHz Arduino boards (e.g. Duemilanove and Nano), this function has a resolution of four microseconds (i.e. the value returned is always a multiple of four). On 8 MHz Arduino boards (e.g. the LilyPad), this function has a resolution of eight microseconds.
It seems likely that the doco was updated some time after the OP posted the question.

72243: <p>Is there any way to know the resolution of micros() for the Arduino Portenta H7. I have checked for other boards e.g. Nano which is mentioned as 4 uS. However, I couldn't find one for Portenta H7.</p>
<p>Is there any way to measure or look for that</p>
 71575: <p>The <strong>micros()</strong> <a href="https://www.arduino.cc/reference/en/language/functions/time/micros/" rel="nofollow noreferrer">language reference</a> states that, &quot;[The micros() function] returns the number of microseconds since the Arduino board began running the current program. This number will overflow (go back to zero), after approximately 70 minutes. <strong>On the boards from the Arduino Portenta family this function has a resolution of one microsecond on all cores.</strong> On 16 MHz Arduino boards (e.g. Duemilanove and Nano), this function has a resolution of four microseconds (i.e. the value returned is always a multiple of four). On 8 MHz Arduino boards (e.g. the LilyPad), this function has a resolution of eight microseconds.</p>
<p>It seems likely that the doco was updated some time after the OP posted the question.</p>
