120 khz with arduino

Forum 2005-2010 (read only) Software Syntax & Programs
4

There is no function that waits shorter than microseconds, sorry.

But you can wait with
asm volatile("nop");

and with my Arduino Diecimila (atmega168 at 16MHz)
the following code is gets very close to 120kHz:

uint8_t outPin = 2;

void setup()
{
  pinMode(outPin, OUTPUT);
  digitalWrite(outPin, LOW);
}

void loop()
{
  digitalWrite(outPin, HIGH);   // sets the pin on
  asm volatile("nop");
  asm volatile("nop");
  asm volatile("nop");
  asm volatile("nop");
  asm volatile("nop");
  asm volatile("nop");
  asm volatile("nop");
  digitalWrite(outPin, LOW);    // sets the pin off
  asm volatile("nop");
  asm volatile("nop");
  asm volatile("nop");
  asm volatile("nop");
  asm volatile("nop");
  asm volatile("nop");
  asm volatile("nop");
}

maybe on your hardware you must try more or less of the nop expressions... and I do not recommend this solution. A timer would be the better choice, but you asked for a software solution.

Oh and your Arduino should do nothing else while he is running this code... why do you need this 120kHz?