Topic: Connecting USB device to 2 non-battery ports = silent freeze

Just what it says.
What's the deal?
If i plugin anything (even a USB flash stick etc) into one of the non-battery powered ports (the two that are on side of board opposite from power connector, it just silently locks up.
If i connect something and power things up, it works - no freeze, device is recognized.

I thought the issue could have been power but I've reconnected to a clean lab supply and total current draw with my USB dongle in powered port and USB flash drive in unpowered port is ~500mA.

2

Re: Connecting USB device to 2 non-battery ports = silent freeze

What are you doing - do you mean you are running the stock kernel/rootfs, it boots up, you are on the console and have something running that is producing output and it stops dead without any kernel panic or error message?

Usually the USB enumerator will print something.

3 (edited by timecop 2010-10-20 16:59:02)

Re: Connecting USB device to 2 non-battery ports = silent freeze

Yes, completely dead.
Just freezes and then reboots (by watchdog I guess).
Stock kernel, rootfs with just gcc installed, and this is right after reboot so none of my modules are installed.

No messages on console whatsoever.
Its just sitting at # prompt.
Using serial console btw.

4

Re: Connecting USB device to 2 non-battery ports = silent freeze

Maybe a hardware problem.  I can't duplicate it but it might be causing a surge somewhere else.

Re: Connecting USB device to 2 non-battery ports = silent freeze

Just tested some more. Plugging in a USB flash stick with no other USB devices connected, right after reboot into non-powered ports = silent freeze, no messages or anything. Does not reboot with watchdog. Powercycling the board without removing same USB flash stick, it will boot up normally and actually recognize the stick and mount it.

P.S. my board came from sparkfun.