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Unread 22-03-2012, 03:55
Tom Bottiglieri Tom Bottiglieri is offline
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Re: Team Fusion #364, Bayou Regional, FMS Woes

Quote:
Originally Posted by Natchez View Post
Thanks & give us your troubleshooting ideas,
Lucien
Knowing what part of the system is broken quickly should help.

I would run tcpdump at three different places and compare the captures to find where packets are getting held up or lost. Run one on the DS (or on the same switch), one over the air (using the team's SSID and PSK), and one behind the robot bridge. You can probably use one laptop to do both of the latter.

Basically what you are looking to do is trace packet flow. Check the timestamps of packets as they move from the DS to the AP to the bridge to the bot. It will be pretty apparent if there is a faulty piece of hardware in the chain. (I'm not as worried about the Cisco AP as I am the Dlink bridge you can buy at Walmart...)

If packets aren't getting delayed or dropped anywhere in that chain, check to see how it takes for replies to be generated by both the DS and cRIO.

PS. You can use Wireshark instead of tcpdump for prettier output, or if you want a GUI.