The speed of Arduino
The speed of Arduino pin as an output
I have read, that Arduino IDE command for setting output HIGH/LOW is slow, takes a lot of cycles for such simple operation. Since it was made for safety and not speed, and sometimes you need only speed, simple change of pin state. I found two fast options, that were pure C code. I made sketch, that toggles pin 13 for 256x and measures time it takes to do so. From results I got, you can change pin stat @ 8MHz, while digitalWrite(); could only do just above 150kHz, doing nothing else!! That is 53x slower.
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