Protection circuitry for ethernet port on brain?

Someone reported to me that they tried connecting an IQ brain to their computer via the included ethernet cable, which resulted in smoke being emitted from the computer. (alarm bells started ringing in my head at this point)

Now they’re experiencing some strange program download issues: No matter what the program is called in VEXcode IQ, downloading results in a program called “xxxxxxxxxxxxxxx” appearing on the brain, and no matter what the program does, running the downloaded program immediately throws the “User program time limit of 3 seconds exceeded” error. I tried as many software and hardware troubleshooting steps as I could over Zoom, but nothing altered this behavior.

Naturally, I strongly suspect these two things are related. What kind of protection circuitry, if any, is there on the IQ brain’s ethernet RJ45 port. I assume the pinout of the brain’s port is different to a normal ethernet port - is there a pinout diagram available somewhere? What sorts of things could get damaged when connecting the brain’s ethernet RJ45 port to a ‘normal’ ethernet port on a computer?


I’m guessing what happened here is that the tether port on the IQ brain was connected to the Ethernet port on their computer. The tether port is meant to provide a wired connection between the controller and the IQ brain, and is not an Ethernet port, even if the connector is the same. I have no idea about protection circuitry, but it seems like the brain is dead anyways. I would highly recommend RMAing the brain, and getting the computer checked out.

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I’ve done this before, and nothing like that happened.

I suggest that there may be some other cause, unrelated to that story

As JoshJ said, It’s not an “ethernet port”, just because it uses an RJ45 connector doesn’t mean it’s ethernet. There is some protection, for example the power output is PTC protected, but if the story about the computer releasing the magic smoke is true, something has probably been damaged and may well be affecting programming.


Me to I have done this before and took me an hour to take out the RJ45 wire from the internet cable but noting broke witch was the good part