Quote:
Originally Posted by Jared
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These ethernet cables run to control cases (SCC's) under the DS shelf, where they plug into an ethernet switch. This ethernet switch is connected to an Allen Bradley Stratix 8000, which has three other ethernet ports that are dedicated to 1, 2, and 3 driver stations. What goes on here is unknown, but it's not unreasonable to expect that there could be delays here. The Allen Bradley box is doing something other than being a switch because it won't work if you plug the wrong team into the wrong ethernet cable.
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FMS timing seems to be properly understood by nobody.
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The switches are managed. Which means they only route packets to specific ports based on the IP address (or MAC). Managed switches are always higher end than generic switches. You are not losing any significant time in the switches. The travel time for Ethernet packets between the DS & robot are logged on the DS. I expect the travel times between FMS & the DS are the same or better.
I expect the FMS timing is understood by the people involved in writing the programs. It just not public information.