Invalid Exception

I had a random issue that has come up a few times since the big IQ and RobotC firmware updates a few weeks ago. I do all the updates myself to ensure they are done properly. I connected all of our bots, motors, brains, and controllers to the IQ firmware updater and can confirm that all motors were recognized and updated. Since then, a team will turn their bot on (different bots, different days, 2 different motors) and will get the message (picture attached). I know this comes up if a motor is not updated but I know I already updated them. When we connect it to the IQ firmware updater, it does say it needs updating. I update it, and it works fine. Yesterday it gave us this message for our gyro sensor too but when we connected to the updater, it said it was up-to-date. My question is if I already did the updates, why am I in essence having to update again? I dont know if this is just a random bug or not but I thought I would let you all know of our issue. I dont think it’s “major” in that when I re-update, the motor works fine and it’s a simple process but a little odd and something I’d rather not have to deal with during a competition!


I am also having that problem on a motor except I think it is the motor itself not firmware because I tried it in a different port and it didn’t work in that port either.

To confirm, you are experiencing this issue on multiple robots with different motors, correct? Does this issue always occur on port 12, or does it occur on other ports as well? Also, can you confirm which version of the VEX IQ firmware and which version of the ROBOTC firmware is being loaded onto the IQ Brains?

You can find the VEX IQ firmware version under the ‘Settings -> System Info’ menu on the IQ Brain (v1.xx), and you can find the ROBOTC firmware version by opening ROBOTC and navigating to the ‘Robot -> Download Firmware -> Standard File (VEX_IQ_XXXX.bin)’ menu option.

Thank you in advance,

Hi John, yes this does happen on random motors/random robots/random ports on brains. One time it came up on port 7, once on port 12, and once on another one (can’t remember but it wasnt a repeat). The ROBOTC firmware is VEX_IQ_1027.bin and the IQ Brain Firmware is 1.13.

This problem for me is a little different – the robot doesn’t even recognize that there is a motor connected to the port. Neither does robotC or the firmware updater. This problem is making me unable to program or do anything useful to the robot.

Hi nathanpitts2002,

If you have having an issue with a Smart Motor where it does not respond on any port of the Robot Brain, then please contact VEX Technical Support at or by calling +1-903-453-0802 so we can help resolve this situation.


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