MiSTer FPGA Forum

Hi, Sorry if I missed it but I haven't been able to find any information on compatible OTG USB (micro to A) hubs.

Back story; skip this paragraph if you want. - I had put my fully functional arcade machine into dry safe storage in a shed for about a year. When my brother visited I pulled it out since he had never seen my arcade machine. It was immaculately clean inside. But it failed to boot. After he left I put more effort into figuring out why and eventually tracked it down to the DE-10/USB Hub (shared) power supply failing. It would work fine after about 5-10 mins of warm up, but obviously I can't trust it. So I ordered a replacement. In the meantime I looked for a power supply I could use temporarily and in a moment of mix-up I stupidly plugged a 12v supply in. That killed my MiSTer USB v2.1 Hub. Fortunately the DE-10 has over voltage protection but, stupidly, the MiSTer USB v2.1 Hub does not. Not having a way to test the micro USB port on the DE-10, I ordered an OTG 4x USB-A Hub from Amazon. But the OTG Hub failed to work with any of my input devices. I don't think I have any other devices that I can test the hub on. Then I realized I could cobble a (Micro to USB-C adapter) to (USB-C to USB-A adapter) and plug my controller into the DE-10 to test the port. That works so I know the DE-10 is ok. Phew.

I would proffer not to buy a replacement MiSTer USB Hub since I didn't so many ports and at its price it should have over-voltage protection since it uses an external power supply. It might be that i'm Australian and we pay heaps for stuff here that seems cheap in the USA, it just seems like a bad deal to me at the moment. Each to their own I guess but I might get another eventually.

In the mean time does anyone know of a list of compatible Micro to USB-A hubs that are compatible?

Thanks, Regards beautiful people.

I just used a regular usb otg cable that I bought from Ebay for 1 dollar, then connected any old usb hub to that adapter. All hubs have worked as they should.

Thanks. I did a similar thing temporarily with a bunch of adapters. Have one that works like that so I might rewire the cable to have a mirco USB instead of it's current USB-A. I do wonder why the one I bought doesn't work.

I also have this, works well.

https://www.adafruit.com/product/2991

Thought someone might be interested in what happened to my solution.

The USB hub that I had on hand that worked with the MiSTer, via the dongle/adapter contraption, is a UGREEN product that is no longer available on their website. Bellow is a photo of the case after I had removed it's contents.

I opened the USB Hub because I wanted to replace the cable, that has a USB-3 connector, with a cable that has a USB-micro connector so it would fit the MiSTer. Bellow are two photos of the PCB assembly. It consists of two PCB's, the main one which has the USB connectors and a daughter PCB that contains various card slots.

This got my attention since I wont be needing the Card slots. So I de-soldered the daughter PCB to see if the Hub works ok without it. It tested good so I decided to continue without it. The main PCB also seemed to be the same width of the MiSTer and would lend itself to being sudo incorporated. You'll see what I mean in photos of that later in the article.

I started on the cable by documenting and then fully de-soldering the cable from the main board. I soldered on an old USB-micro cable that I had cut off the USB-A end. I did this to test that it will still work ok without all the USB-3 stuff. I assumed it would but wanted to be sure. Having confirmed that I de-soldered the test cable. I had some spare USB-Micro custom cable parts. See photo bellow what what that looks like.

I soldered some silicon sheathed wire to the USB-micro connector and to the main PCB. I made the wires long enough to work with but not too long to be in the way. I twisted the data cables. Although I don't know that such short length would really require this. See photos bellow. The photo of the USB-micro connector with wires soldered onto it is not mine and the connector is slightly different to the ones I have but makes no difference here.

With that done I tested again. Photo bellow:

Previously I had the MiSTer and it's stack of 3 PCB's attached via some plastic L shaped stand-offs and plastic screws to offer the MiSTer some protection. You can see them in the photos bellow. Now with this idea I wanted to go with the sudo integration idea so I created a mounting plate from 2.3mm ply. To keep the mounting plate very close to the MiSTer PCB I had to do a couple of things. I created spacers to prevent the screws from possibly bending and damaging the board when tightened down. I also created some spacers right next to the USB hub connecters to offer some protection to the USB hub. You can't see these very well in the photos. Additionally I decided not to screw right into the ply. I have done this in the past without much issue but I decided to insert the nuts into the ply and the spacers will stop them being pulled through. Although technically they can be pulled out separating the mounting plate from the MiSTer but the nuts are a very tight pressure fit.

Hope you enjoyed and it inspires someone to do their own custom changes to things.

You're gonna zap that thing one day, better get it covered up. It's a real concern on these boards, fingers should never be near the PCB.

Yea. It’s normal location is inside my arcade cabinet. With all external controls. Only time I would normally go near it is if I have issues or need to make changes. Most of which I can do via wi-fi anyway. Thank you for your concern.