V5 brain/controller Micro USB swap with USB-C

VEX V5 General Discussion
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Heyo

This summer I bought my old high school V5 competition robot and parts after the school shut down, and just now got time to mess around with it. But I’ve been having trouble with the Micro USB ports on both the brain and the controller, neither will show up in VEXcode or device manager.

I’ve followed the guide and tried restarting, different computers & cables, reinstalled drivers, to no success.

I’m not planning to use them for competition, and the warranty is long expired. So I figured I might try to swap the micro USB with USB-C. Has anyone done this before? Or know someone who has? I’m planning to do the controller first since it’s cheaper to replace if I mess up.

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I haven’t replaced Micro USB sockets neither on V5 controller nor on V5 brain, but I have repaired and/or replaced them on a number of wireless headphones, arduino/esp32 boards, and an android tablet. There are a few tips.

First of all, just try to touch up an existing solder joints with fine tip soldering iron with an aid of a lot of flux. If the problem is fractured solder joints you may get it to work without the need to remove and replace the socket. If that works use magnetic USB dongle to limit the stress on the socket in the future.

If that doesn’t work, then you may need to replace it. However, a random Micro USB socket off Ebay (let alone USB-C) may not be compatible with existing PCB solder pads. Then your best strategy would be to solder thin wires to PCB for GND, 5V, D+ and D- connections and use separate breakout board with USB socket hot glued to the case.

Finally, unless you have experience soldering and desoldering delicate smt components, practice on something disposable like a USB breakout board first. It may be safer just to attach thin wires without removing old connector.

Post pictures as you go, somebody else may have good tips.

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It may not be as easy as that, IIRC USB-C may need different pull-up/pulldown resistors and there will be, due to the USB-C connector being able to be rotated, more connections needed.

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Update, not good news

I took apart and inspected the existing joints as suggested, they looked fine I couldnt see any damage though I don’t have my microscope right now.

So I ordered some USB-C connectors off Amazon these ones specifically, the plan being to use wires to bridge the pads.

https://www.amazon.com/gp/aw/d/B091CRLJM2

I tested them with a multimeter and in both orientations the data and power pads remain correctly connected. They’ve got traces on the PCB setup to make sure nothing gets flipped.
I also tested the wiring of the Micro USB port, it’s as follows left to right, from above looking down.

GND , D+ , D- , ID , VCC

From what I understand the ID pin is used for mobile to mobile type connections where you can change which device is the host, but it shouldn’t matter in this case (I wasn’t able to test).

Wiring to the USB-C was easy, I found that the wires within a V5 cable are actually pretty good and took solder easy.

Now the bad stuff, taking the Micro USB off. The supporting legs took about 20 seconds of heat and a solder wick pad before they came free. The pins, however, because of their proximity to some SMCs made it much more difficult to apply heat but I thought I got them cleared out.

But unfortunately, underneath the port, is a large support pad that it is soldered to, and I didn’t know about. So when I attempted to take the port off, it didnt budge. Instead of reevaluating I cave man’d it and forced it off, and it did come off. But also took every single pad off with it :skull:

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Yeah, not good. I tried scrapping the mask off the traces, and for GND and VCC that did work. The traces go to FB1 and FB2 respectively. But there just wasn’t enough for the D+ and D- pins.

So I’ve got a new one ordered from VEX, and a magnetic cable from Amazon. If someone had the proper setup and tools they’d be able to get it done, but because VEX doesn’t like electronics modding there’s no reason to do it for comp teams. Hopefully they just release a USB-C one themselves.

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