#Arduino analogwrite vs digitalwrite how to#
#Arduino analogwrite vs digitalwrite serial#

We have the answer: a digitalWrite() will take 3.40 microseconds to execute on an Arduino Uno board.

#Arduino analogwrite vs digitalwrite serial#

So, if you run this code, and open the Serial Monitor, you’ll get something like this (on Arduino Uno): Total duration: 3396 µs

#Arduino analogwrite vs digitalwrite how to#

To get more details and explanations about this code, check out How to compute a duration with Arduino. This code will print the total duration required to execute 1000 digitalWrite(), and then print the average duration for only one digitalWrite(). Serial.print('Duration for one digitalWrite(): ') Unsigned long totalDuration = timeEnd - timeBegin ĭouble duration = (double)totalDuration / 1000.0 It’s often better to take a large sample instead of just measuring only one action. In order to get an accurate measurement, we’ll execute digitalWrite() 1000 times and then divide the result by 1000. Then we’ll be able to improve it, and measure it again to see how much time we save. So, let’s see how much time the digitalWrite() takes. Optimizing stuff is cool, but if you don’t know what you’re optimizing, and by how much, then there’s no point. Why Arduino digitalWrite() is not fast Measuring digitalWrite() speed Just use the tips when you really need them. Applying the tips on all your Arduino projects though is not something I would recommend. Note that even if you don’t need to optimize your code, reading this tutorial can still be useful to understand a few things about Arduino. You are learning how to use Arduino to build your own projects?Ĭheck out Arduino For Beginners and learn step by step. So, be sure you actually need to optimize before you do. If your application consists of switching a digital pin every 100 ms, and if you don’t have any real time constraints, then don’t bother optimizing, you’ll just waste your time.Īs Donald Knuth said: “Premature optimization is the root of all evil.” When you should optimize (and when you shouldn’t)īefore going any further, I want to emphasize this: don’t try to optimize a code too soon, especially if there’s nothing wrong with it. Going further with Arduino fast digitalWrite().Arduino Blink LED example using fast digitalWrite().Direct port manipulation changes all the pin’s states.Using direct port manipulation instead of digitalWrite().When you should optimize (and when you shouldn’t).