Just an update to my original post folks. I took a close look at the USB header and one of the data pins had a fat glob of solder on it. So fat that both bins are soldered together (or just about), in fact. That certainly explains why things attached to the USB port could draw power but not be recognized.
I bought a 3 A power supply and am now using that instead of 1 or 2aA over USB. USB hub now works great.
Is it the current or maybe the that is has a good ground? Is it a two or three prong power supply? Linear or switcher?
Gerald
It’s not a bench supply, if that’s what you mean.
Not that is not what I mean. Some suppliers are linear and others are switchers. Switchers can be noisy. My biggest question if it is three prong supply or just two. I’m looking for a good ground. The USB is limited to 500mA, so adding a high amperage supply has no affect on that fact.
Gerald
Hi,
Though this thread is old, I thought I’d take a shot at asking you a question, because this comment is the closest thing to an answer I’ve found for a problem I’m facing.
I’m attempting to interface my BBB with a custom device via USB. The device is set up as a CDC class device. I’m able to send a character to the device and get a response with write/read C functions, but only once - whether I attempt to write/read more than once within a program or attempt to run the same program more than once without rebooting the BBB.
Is this what you meant by it working “once and then will not after that”? I haven’t been able to find a solution, but are you aware of anything popping up since May?
Yes. I have the same problem. After I boot my BB via sd card which has a version 3.8.13, I noticed that USB ethernet
26 Mayıs 2013 Pazar 15:58:46 UTC+3 tarihinde Brent yazdı: