Folks, for anyone interested, here is elapsedMillis and elapsedMicros (adapted by pfeerick from work done by Paul Stoffregen) simplifies timing loops a lot. This codes required NO adaptation for the Spark so I take no credit

Here it is with an simple LED blink example. Cheers!

```
// -------- elapsedMillis.h --------
/* Elapsed time types - for easy-to-use measurements of elapsed time
* http://www.pjrc.com/teensy/
* Copyright (c) 2011 PJRC.COM, LLC
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
class elapsedMillis
{
private:
unsigned long ms;
public:
elapsedMillis(void) { ms = millis(); }
elapsedMillis(unsigned long val) { ms = millis() - val; }
elapsedMillis(const elapsedMillis &orig) { ms = orig.ms; }
operator unsigned long () const { return millis() - ms; }
elapsedMillis & operator = (const elapsedMillis &rhs) { ms = rhs.ms; return *this; }
elapsedMillis & operator = (unsigned long val) { ms = millis() - val; return *this; }
elapsedMillis & operator -= (unsigned long val) { ms += val ; return *this; }
elapsedMillis & operator += (unsigned long val) { ms -= val ; return *this; }
elapsedMillis operator - (int val) const { elapsedMillis r(*this); r.ms += val; return r; }
elapsedMillis operator - (unsigned int val) const { elapsedMillis r(*this); r.ms += val; return r; }
elapsedMillis operator - (long val) const { elapsedMillis r(*this); r.ms += val; return r; }
elapsedMillis operator - (unsigned long val) const { elapsedMillis r(*this); r.ms += val; return r; }
elapsedMillis operator + (int val) const { elapsedMillis r(*this); r.ms -= val; return r; }
elapsedMillis operator + (unsigned int val) const { elapsedMillis r(*this); r.ms -= val; return r; }
elapsedMillis operator + (long val) const { elapsedMillis r(*this); r.ms -= val; return r; }
elapsedMillis operator + (unsigned long val) const { elapsedMillis r(*this); r.ms -= val; return r; }
};
class elapsedMicros
{
private:
unsigned long us;
public:
elapsedMicros(void) { us = micros(); }
elapsedMicros(unsigned long val) { us = micros() - val; }
elapsedMicros(const elapsedMicros &orig) { us = orig.us; }
operator unsigned long () const { return micros() - us; }
elapsedMicros & operator = (const elapsedMicros &rhs) { us = rhs.us; return *this; }
elapsedMicros & operator = (unsigned long val) { us = micros() - val; return *this; }
elapsedMicros & operator -= (unsigned long val) { us += val ; return *this; }
elapsedMicros & operator += (unsigned long val) { us -= val ; return *this; }
elapsedMicros operator - (int val) const { elapsedMicros r(*this); r.us += val; return r; }
elapsedMicros operator - (unsigned int val) const { elapsedMicros r(*this); r.us += val; return r; }
elapsedMicros operator - (long val) const { elapsedMicros r(*this); r.us += val; return r; }
elapsedMicros operator - (unsigned long val) const { elapsedMicros r(*this); r.us += val; return r; }
elapsedMicros operator + (int val) const { elapsedMicros r(*this); r.us -= val; return r; }
elapsedMicros operator + (unsigned int val) const { elapsedMicros r(*this); r.us -= val; return r; }
elapsedMicros operator + (long val) const { elapsedMicros r(*this); r.us -= val; return r; }
elapsedMicros operator + (unsigned long val) const { elapsedMicros r(*this); r.us -= val; return r; }
};
// -------- end elapsedMillis.h --------
elapsedMillis timeElapsed; //declare global if you don't want it reset every time loop runs
// Pin 13 has an LED connected on most Arduino boards.
int led = D7;
// delay in milliseconds between blinks of the LED
unsigned int interval = 1000;
// state of the LED = LOW is off, HIGH is on
boolean ledState = LOW;
void setup()
{
// initialize the digital pin as an output.
pinMode(led, OUTPUT);
}
void loop()
{
if (timeElapsed > interval)
{
ledState = !ledState; // toggle the state from HIGH to LOW to HIGH to LOW ...
digitalWrite(led, ledState);
timeElapsed = 0; // reset the counter to 0 so the counting starts over...
}
```