If someone asked you how "fast" an ardui

Forum 2005-2010 (read only) General Frequently-Asked Questions
4

Hi,

To satisfy my curiosity I compiled and ran the following sketch on a Diecimila:

/*

  • SpeedTest
  • JRG 2009.03.21

*/

void setup()
{
pinMode(13, OUTPUT);
}

void loop()
{
digitalWrite(13, HIGH);
digitalWrite(13, LOW);
}

Using my scope to observe the output of pin 13 I find:

on time = 3.312 us
off time = 3.917 us
frequency = 136.642 KHz

So using the Arduino IDE instructions is significantly slower than using direct port I/O .

John