Arduino - DelayMicroseconds

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delayMicroseconds()

Description

Pauses the program for the amount of time (in microseconds) specified as parameter. There are a thousand microseconds in a millisecond, and a million microseconds in a second.

Currently, the largest value that will produce an accurate delay is 16383. This could change in future Arduino releases. For delays longer than a few thousand microseconds, you should use delay() instead.

Parameters

us: the number of microseconds to pause (unsigned int)

Returns

None

Example

 
int outPin = 8;                 // digital pin 8

void setup()
{
  pinMode(outPin, OUTPUT);      // sets the digital pin as output
}

void loop()
{
  digitalWrite(outPin, HIGH);   // sets the pin on
  delayMicroseconds(50);        // pauses for 50 microseconds      
  digitalWrite(outPin, LOW);    // sets the pin off
  delayMicroseconds(50);        // pauses for 50 microseconds      
}

configures pin number 8 to work as an output pin. It sends a train of pulses with 100 microseconds period.

Caveats and Known Issues

This function works very accurately in the range 3 microseconds and up. We cannot assure that delayMicroseconds will perform precisely for smaller delay-times.

To ensure more accurate delays, this functions disables interrupts during its operation, meaning that some things (like receiving serial data, or incrementing the value returned by millis()) will not happen during the delay. Thus, you should only use this function for short delays, and use delay() for longer ones.

delayMicroseconds(0) will generate a much longer delay than expected (~1020 us) as will using negative numbers as a parameter.