USB Issues

[TheShaner]

I am starting to think I have too many USB devices running.  Things can get a little flakey at times.  USB devices pick up and drop here and there.  So where I have the trackball at mouse1 at first, later on in a session, it might have dropped and picked back up as mouse3. 

I do have a crappy chinese made USB hub, which is being replaced by a Belkin 4 port here in the next day or two, but I am still leery.  All of these are just coming off of one USB Channel on the motherboard I think.  (The 4 that are there are really just a distribution of 1 port actually on the board I believe if I understand my technology correctly.)  So I am debating whether that is really an issue or not, and if so, whether I should go pick up a couple of PCI Express USB extenders to give me some more ports without just throwing hubs all over the place. 

Anyone have any experience in this realm?

[MacGyver]

Happens to the best of us, check out drventure's excellent tool designed to hide the issue in MAME called "ControllerRemap".
http://forum.arcadecontrols.com/index.php?topic=108767.0

[drventure]

Oh yeah. Just a bit.

The main things to keep in mind

1) cheap hubs tend to be cheap hubs. They'll work fine if they're the only thing in the chain, but if not watch out.
2) Unpowered hubs are generally your enemy. Use powered hubs as much as possible.

Also keep in mind that most USB hub power supplies won't provide anywhere near the max power to all ports.

I've found 7 port hubs with a 1000mw power supply before. Since each port could theoretically draw upto about 500mw, that'd be way underpowered if you actually connected 7 high draw devices.

That should relieve most problems.

If you actually DO unplug and reconnect devices though, windows WILL renumber them, often in ways that break everything. That's the whole reason for my ControllerRemap utility (see my sig)

Opps, looks like MacGuyver already mentioned it....

[TheShaner]

Cool, good advice.  I should have my belkin tomorrow, which is powered and hopefully that will help.  I am going to read more into your software right now, I'm intrigued ...

[PL1]

2) Unpowered hubs are generally your enemy. Use powered hubs as much as possible.

Also keep in mind that most USB hub power supplies won't provide anywhere near the max power to all ports.

I've found 7 port hubs with a 1000mw power supply before. Since each port could theoretically draw upto about 500mw, that'd be way underpowered if you actually connected 7 high draw devices.

Very true, but for certain portable applications you might want to use an unpowered hub.

The USB current draw spec for an unpowered 4-port hub is 100 mA per port, though most manufacturers don't always restrict it that much.

It is easy to exceed that, but you can work around it if you're careful.

I built a USB 5V lighting circuit for a portable modular panel with 3 LEDs (trackball) and 14 12V LED buttons from Paradise.  It only draws 81 mA instead of the 340 mA you would expect if you ran the buttons at 12V with no additional current limiting resistor beyond the resistors built into the LED buttons.


Scott

[Nephasth]

I've got a USB PCI card. It has added 5 USB ports to my computer. Right now I have a total of 7 USB devices hooked up (8 when I use my thumb drive for updating), 4 on the PCI card and 3 in the "stock" USB ports (4) of the mobo. I'll probably be adding 4 more USB devices in the near future, at which point I will be picking up another PCI card. Never had any USB problems with this setup.

[TheShaner]

I'm thinking along the same lines Neph.

[Drnick]

Powered USB Hubs or PCI Expansion cards are definitely the way to go on this one. Talking of which I really need to find my powered hub