time synchronization problem

Hi,

I have a problem concerning time synchronization with two devices. Both devices has the following interrupt routine:

Code:

---

uint16_t time;
uint16_t mark;
INTERVAL = 10;

slotInterval = 1000;

Timer.fired()
{
  time = time + INTERVAL;

  if((time - mark) > slotInterval)
  {
    //SEND MSG by radio

    mark = time;
  }
}

---

And on the reception device:

Code:

---

ReceiveMsg.receive(TOS_MsgPtr msg)
{
  //Note rTime  is designated as uint16_t as well
  // and is what is sent from the other device when timer fires
 
  uint32_t newTime:

  newTime = ((uint32)rTime + (uint32_t)time) / 2;

  if(newTime > MAX_VALUE)
      newTime = newtime - MAX VALUE;

  time = (uint16_t)newTime;

}

---

My problem becomes when the time overflows and mark is still a higher value. What I want to do is average their both devices time value so that it doesn't differ too much for time synchronization. They should be exactly the same. Anyone has a suggestion how to fix this or even another solution that is better?

Thanks a million.

Inderjit

Not precisely sure what you're doing, but..

Code:

---

  if(newTime > MAX_VALUE)
      newTime = newtime - MAX VALUE;

---

Do you mean :

Code:

---

  if(newTime > MAX_VALUE)
      newTime = MAX VALUE;

---

?

:)