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Can Arduino calculate time?
Often, you need to measure the time your microcontroller takes to perform a particular task. You can use the millis() function of Arduino to measure the time. This function returns the number of milliseconds passed since your board started running the current program.
Is Arduino a real time system?
Arduino has announced that Intel has released the Arduino 101 real time operating system (RTOS) for hacking and studying purposes. According to its own description, Arduino aims to be a fully open-source project, including both its hardware and software.
What do you need to know about Millis timing?
To use millis () for timing you need to record the time at which an action took place to start the timing period and then to check at frequent intervals whether the required period has elapsed. If so, you presumably want to do something, otherwise why would you be timing ?
How does the Arduino sketch calculate Millis count?
The sketch stores the current millis count in start, then waits one second, then stores the value of millis again in finished. Finally it calculates the elapsed time of the delay. In the following screen dump of the serial monitor, you can see that the duration was not always exactly 1000 milliseconds:
How is Millis used in the state machine?
Note that we have variables to keep track of whether the LED is ON or OFF. And variables to keep track of when the last change happened. That is the State part of the State Machine. We also have code that looks at the state and decides when and how it needs to change. That is the Machine part.
How does the Millis clock work in Blink?
On each pass through the loop, it looks at the millis () clock to see if it is time to change the state of the LED again. Let’s look at a slightly more interesting blink variant that has a different on-time and off-time. We’ll call this one “FlashWithoutDelay”.