Hi all.
I am having a problem with the smallest unit of time which Arduino 2560 can be measured and return.
I have used White LED to transmit data and Photodiode to recieve these data. I am using millis() function, but the value which it return is millisecond. it is too long in communication.
So i would like to ask all of you that having any function which can measure and return value of time smaller than unit of millisecond.
Thanks in advance! 
micros ()
Thank you again and again 
QuaanNguyeen94:
Hi all.
I am having a problem with the smallest unit of time which Arduino 2560 can be measured and return.
I have used White LED to transmit data and Photodiode to recieve these data. I am using millis() function, but the value which it return is millisecond. it is too long in communication.
So i would like to ask all of you that having any function which can measure and return value of time smaller than unit of millisecond.
Thanks in advance!
Note that if you change the time scale of the timer you can get your timer resolution down to 1/2 microseconds. Marice Ribble uses that technique in his "Camera Axe" program for Arduino. You can find his source here:
Measured and return... makes it a bit more difficult but for pure measure there have been discussions on inline pin reads with variable increments down to a few cycles.
If the event could charge a capacitor that could then bleed through a resistor to a pin, the time that would take would be lengthened. But it would need calibrating and might be otherwise prone to some kind of error.