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Unread 12-12-2008, 19:27
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AKA: Eric Anderson
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Re: Wireless options for 2nd system

Quote:
Originally Posted by EHaskins View Post
Actually, the IP/subnet of the router interface is irrelevant to this. The router provided is, functionally, a 6 port switch with one port connected to a wireless access point, another connected to a router/NAT device, and four ports exposed for our use.

Since we are only communicating on a LAN, i.e. on a single switch, router device is never involved in the communications between the DS and the cRio.

You can test this by changing the Ip address of the router to something else. It will still work.

/Explanation

So long as each device has its own IP, which happens if you change you team number, and the subnet masks of the devices communicating(DSs and cRios) match, then it will work.

If you don't read my whole post, if you change the team number on one DS and one cRio, then they will connect and not interfere.

If you have any questions I'll try to explain it more.
Our experience was a bit different during the beta period. I agree that what you say should be the case, but it does not seem to be in the case of the linksys router that we were shipped with. The router appears to do some filtering on the switch that interferes with having multiple subnets.

I'd be happy to hear if any one has an explanation for what we observed.

Case 1) router out of the box - IP address 192.168.0.1, - everything worked fine, using static IP for computers and robot (set to 10.0.0.X or 10.14.25.X depending on where we were in the configuration process).

Case 2) router set to 10.14.25.1 with DHCP enabled, netmask 255.255.255.0.

In this case things work well except if we need to reimage the cRIO using the imaging tool (format, not just retarget C++ - Labview). If the robot was connected directly to the router, the re image would fail due to network failure at the point where the IP address was changed. If the robot was attached wirelessly, the reformat/reimage process would work.

This leads me to belive that the router would not be well behaved if you are trying to use a different team number.
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