terryjmyers / pulsetimer

Arduino Library: Creates a boolean that is set true for one loop of the code based on a preconfigured time.

Pulse Timer

PulseTimer

Created by Terry Myers Dec 2016

v1.0

Creates a boolean that is set true for one loop of the code based on a preconfigured time. The error created by varying loop times is automatically subtracted out. For example, a 1000ms pulse: When PulseTimer.tick() is called 1002ms has passed since the last pulse, the pulse bit is set and 2ms is subtracted. The next pulse will be "scheduled" to occur 998 ms later.

This allows precise timing functions to occur code that may have a variable loop time:

1. create very long timers
2. Create a 1000ms pulse timer. Each pulse add 1 to an unsigned long integer thereby creating a timer with a resolution of 1 sec but a possible duration of 136years!
3. Place in front of Serial.print debug logic to prevent flooding of the serial monitor
4. Call input and output mapping functions on regular intervals
5. Call integration routines such as integrating a current/power analog input to get Wh or mAH

Use:

Initialze the timer by creating a PulseTimer class and giving it a timer preset value in ms

Place only one call PulseTimer.tick() function in your loop code. Its expected that the call to tick() will occur only once each loop.

This class has been tested with the rollover of millis()

This class has been tested to be as accurate for timing purposes as the millis() function can be irrespective of the main loops processing time

Limitations:

You cannot create a pulse timer that is shorter than double your loop time or the bit will be on all of the timer (Nyquist Theorem).

tips:

1. Place all PulseTimer.tick() functions at the bottom of the loop code
2. When using multiple timers to trigger code try using timers with prime number of ms to prevent overlap.