Micro Usb Broken and little time till competition

My school’s robotics team has at least two years of inactivity and the warranty is off the table. All the pieces were handed down to this year’s team, but one of the brain’s micro USB is broken. There are no extras and we go to competition in a little bit less than two months. I was able to get a micro sd card and later learn about wireless program download thinking I could skip the problem. But it just so happens the brain is one version behind, and it will not let me download programs. I have heard I could try and send the brain back to vex and get it repaired, but I can’t risk the brain to come fixed too late. Is there a way to update the brain through an SD card?

You can pair a controller to the brain, then connect the controller to your computer and upload code wirelessly. Develop the habit of not disconnecting the controller after every upload to protect that port.

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Another way to protect the port is to use something like this: https://www.amazon.com/Extension-Micro-B-Transferring-Suitable-Samsung/dp/B07MC7YSR2/, and keep it permanently in the port, except in compactions. When this wares out, it is a cheap replacement, instead of replacing the brain or controller

sadly you cannot update the brain firmware wirelessly, the ports on the brains really sucks and breaks very easily. In the future I’d recommend never using the brain port to download programs, and instead using the controller port, which in my experience is much more accessible and robust. You can also use some sort of dongle to prevent needing to constantly plug in and remove a cable from either brain or controller ports.


What version is the brain on ? There has been more than one version released in the last two years.

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If the microUSB hardware is broken on the V5 Brain, there is no way to update the V5 Brain to latest firmware (over the air or SDcard)? If that is the case, isn’t the only route the team to update their V5 brain to latest OS is to send it back to VEX either RMA or blanket cost (up to two such repair cost).

My advise for team near term is to reach out to known local teams for loaner, and RECF Team Engagement Manager to help find organizations to help them in their region).

I would encourage to have a solution for firmware updates via SD card (but might not be possible due to architecture of V5 Brain). This is a common problem. For teams that have only one V5 brain and competition the coming weekend, could be a season killer.


I’m aware that this is a problem for teams and will probably become even more of an issue as the hardware ages. I don’t really want to talk too much about things we can/could do but have never released, however, from a technical standpoint it is possible to both update from an SD Card and also via the controller.

The hooks to allow update from SD Card were added in vexos 1.0.10 (march 2020). This works in a similar way to the battery medic program, you send via the controller a small program that then allows update from SD Card. What I don’t have is a delivery mechanism for this, that is, we have never had time to create a web site or app that would allow this code to be installed or the vexos file to be downloaded. I had hoped to test out at worlds in 2020, and again in 2021 before releasing, but things happened… Unfortunately there is still no short term plan for release of this capability, but it will happen at some point.

I’ve also tested update via the controller, preferably tethered, it takes about 7 minutes and I’ve tested updates from vexos version 1.0.7 and later. Again, plan would be a web site that would allow this (using web serial, similar to the remote tournament control), but that’s also been lowish priority as we had so many other things going on this year.

There’s always much more involved that “just making it work”, many other people get involve with documentation, kb articles etc. and we also need to understand what we will do if (when) the update fails as the brain may end up in a worse state than it was to start with.


How do you download code to the controller? through the micro usb port on it?

yes, the controller can be plugged into your computer and code can be wirelessly downloaded to the brain from the controller.

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fascinating, never knew that. Thanks

The current version is VEXos 1.0.9

ok, that’s what I was afraid of.
even if I we had rolled out the SD Card solution, 1.0.9 is too old to support it.
you are actually 5 versions out of date.


Always appreciate the straight answer you give. I think we all appreciate how unexpectedly everyones plans were throw for a loop with the pandemic. VEX/RECF pull out amazing things to keep roboteers engaged and challenged throughout the pandemic. Now with backlog of chips shortage, and delivery pipelines clogged keeping gear running is in the foreground.

As you point out, gear will be aging and the microUSB was fragile interface for V5 Brain. Hoping that the SDcard solution or tethering or website solution gets into the roadmap.


Just curious, how much extra flash space is on the controller? Would it be possible for the update to download and save to the controller, and then, it slowly updates the brain, while you can do something else? Also, I feel like 7 or 8 minutes for the update would not be that bad, as updates don’t come out every day.

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nowhere near enough
The vexcode download is about 6MB, not huge, but takes time over a slow link.
The controller has (IIRC, so don’t quote me) about 128K of flash, and most is already used for the controller firmware.

Update using a controller tethered to a smartport (tethered is faster and more reliable) works fairly well, I don’t really know why we avoided allowing that from the beginning other than the opportunity for something to go wrong and corrupt the brain increases (battery may fail, user may get bored waiting and disconnect etc.).


how is it broken, is it bent or just not working?

The micro USB port has been completely yanked off. Someone was not paying attention or being careful in the past. The port is just “dancing” inside the compartment/brain.

You mean the connector is still rattling around inside the brain, if so, that’s not good, it may cause damage.


Should I unscrew the brain and remove the piece?

I think it’s probably best to contact vex support and try and get the brain repaired.