Issue 19 in beagleboard: Plugging in a usb OTG cable will prevent Beagle from booting

I have USB OTG working on Latest OMAP GIT, I just used default Config in kernel, my version of u-boot 1.3.3 and MLO.

Please test the attached images on your board and let me know if you still find the issue, if it is something to do with u-boot then lets debug that further.

Regards,
Khasim

u-boot.bin (700 KB)

uImage (1.55 MB)

MLO (16.3 KB)

Hi all:

I have USB OTG working on Latest OMAP GIT, I just used default Config in kernel, my version of u-boot 1.3.3 and MLO.

Please test the attached images on your board and let me know if you still find the issue, if it is something to do with u-boot then lets debug that further.

(12:36:56 PM) khasim: all: Floating USB mini B to USB A cable works for me on Beagle
(12:37:18 PM) khasim: but Floating USB mini A to USB A doesn’t boot completely
(12:38:20 PM) khasim: the reason is: We have OTG and ethernet gadget enabled, the USB stack is trying to send DHCP over this, as we have it floating we don’t receive any responce.
(12:39:39 PM) khasim: If we disable ethernet gadget or select any other mode liek File-backed storage gadget then it boots fine for floating mini A cable as well

Regards,
Khasim

Syed,

Unfortunately I wasn't able to duplicate your success. I did discover
that my board *will* boot if connected to a Cyberpower hub, but will
not boot when connected to an IOGear hub.

After further research I'm fairly certain that this is a hardware
issue: unlike the EVM, the beagle design does not include filter
capacitors on VBUS. If you probe VBUS when the USB OTG adapter cable
is connected you will see that it is not a clean 5V -- it has several
volts of AC noise. The Cyberpower hub has VBUS filtering -- as soon
as it is connected VBUS becomes a clean 5V signal. IOGear probably
doesn't filter VBUS, because the signal stays just as ugly as before
it was connected.

To test this theory I piggy-back soldered a 2.2UF ceramic capacitor to
D3. After this hardware mod my beagle works in all cases: naked
cable, IOGear hub, and Cyberpower hub.

I think the USB HW design should be given a closer look prior to
releasing the next rev. I believe it needs the addition of filter
caps on VBUS, and I also believe that it may be missing series
resistors on the DN and DP signals (same goes for USB host port).

Steve

Can you post a photo of the mod? I'd like to try this.

Philip

Is this under a DC powered mode or is the Beagle pulling power from the
hub?

Gerald