I have been looking at the PPP documentation but cannot determine a clear way of making sure the PPP link is still valid. I know that PPP under Windows XP Pro does not have a clue if the client dies (in my case the Rabbit processor). I will have to implement some time of watch dog on the XP side.
Is there a status function that will test the link or should I just use a ping or something similar?
I am thinking I can embed a watchdog that gets reset by a ping from the Windows XP machine acting as a host/proxy to the network. My target for the host is actually Unix, but the implementation would be very similar. If the host does not receive a ping then reset the connection. If the rabbit processor does not get pinged then reset the PPP connection.
Has anyone done this before?
Yes, I have done this before on the rabbit side. All you have to do is have the rabbit ping the host/client every 30 seconds. I also pinged it 3 to 4 times if no response then bring down PPP and then bring it back up. You an do same on the windows side.
I will look into doing just that. I will also see if there is a hook to check to see if I was pinged. That way I know if the application on the other side is working as well. Kind of a heart beat of a heart beat.
Alright, I got the ping callback to work. Right now I am connected to the Rabbit using PPP over serial and I am pinging the LP3500. I have setup the callback function to turn the 1st LED on or off (toggles) on each ping. The callback also tells the program to provide the standard response to the ping. So now I just need to use this callback function to update a watchdog for the PPP connection. This is very cool because I can tell if the connection is good and if the program is running on the PC.
Thanks for your help tgarcia,