Transmitting data to the cRIO from the Driver's station via TCP/UDP

[Mark McLeod]

You're missing a Wait in the second block diagram.
That will suck all the life out of your CPU.

[Alan Anderson]

Originally Posted by Mark McLeod

You're missing a Wait in the second block diagram.
That will suck all the life out of your CPU.

I haven't memorized the UDP function icons, so I might be reading it backwards, but I think that second diagram is the receive processing. As such, it will only run when a new UDP packet is received (or until the UDP receive timeout occurs, which is 25 seconds by default). It doesn't need a Wait inside the loop, and adding one can actually cause some undesired effects if packets arrive faster than the loop time.

[PSHRobotics]

Well we did have a wait in there (30 ms), but while using the debug-run we started to get watchdog errors which had us loose control for a few moments about every 10 seconds. Those errors were more or less random and we had times where they would not happen for about a minute and then they would continuously happen. After taking out that wait we stopped seeing that problem and actually thought we had everything fixed - until we did a "run as startup".

[Alex698]

Originally Posted by PSHRobotics

Well we did have a wait in there (30 ms), but while using the debug-run we started to get watchdog errors which had us loose control for a few moments about every 10 seconds. Those errors were more or less random and we had times where they would not happen for about a minute and then they would continuously happen. After taking out that wait we stopped seeing that problem and actually thought we had everything fixed - until we did a "run as startup".

I was having the exact same problem and it was driving me nuts, however I think I have resolved the issue. I stopped having driver station interference problems when I used a String-to-IP function fed into the open UDP VI into the net address input. It should match your team IP: 10.te.am.02. Also you should set the UDP Write VI net address to your team IP.

[PSHRobotics]

Originally Posted by Alex698

I was having the exact same problem and it was driving me nuts, however I think I have resolved the issue. I stopped having driver station interference problems when I used a String-to-IP function fed into the open UDP VI into the net address input. It should match your team IP: 10.te.am.02. Also you should set the UDP Write VI net address to your team IP.

That is a good catch, and if we get a chance we will try that, thanks!
My only concern about that is that we were able to send data using our code to the robot so the actual communication was not having problems, and because the open is outside of all loops I don't see how it could have caused the communication indeterminacy/watchdog errors when the communication was working.

We did have the UDP Write VI using our team IP (which we got using the global variable for Robot IP).