OTG Port

[Matthias_H]

Hi,


I just tried to connect a full-speed (12Mbps) USB device to my brand new Pandora's OTG port, and a high-speed (480Mbps) external hard disk to both USB ports, with no success whatsoever.


Full-speed device at host port : dmesg: "hub 1-0:1-0: unable to enumerate", well, duh, the device is only full-speed.


OTG port : dmesg: "usb 2-1: new high speed [sic!] USB device using musb_hdrc and address 10"


High-speed HDD at host port : nothing


OTG port : dmesg: all kinds of errors, "device descriptor read/64, error -110; not accepting address 12/13, etc"


What am I doing wrong?


Cheers,


Matthias

 

[ibisum]

Use a powered hub, always.

 

[meandu229]

There is a problem with the usb in that if you plug in a non usb 2 device it needs a reboot before you can use a usb 2 device, also try using a hub as the host port only supports usb 2 usb 1.0/1.1 needs to be upconverted by a hub.

 

[Matthias_H]

There is a problem with the usb in that if you plug in a non usb 2 device it needs a reboot before you can use a usb 2 device, also try using a hub as the host port only supports usb 2 usb 1.0/1.1 needs to be upconverted by a hub.

Are you sure you're not talking about the regular large USB-A port? The way I understood it, the OTG port (mini-A) would support everything right from the start, up to 100mA.

 

[Matthias_H]

Use a powered hub, always.

If I may,

• Says who?
  
• Why?
  

 

[WizardStan]

If you plug a USB1.1 device into the USB-A port, the entire USB host crashes. This is most likely a problem with the OMAP chip itself since it also affects the BeagleBoard. That's why you got no response when you plugged the hard drive in. You need to restart, as mentioned, and use a hub for full speed devices.


You are right about the OTG port though, if you've got the right adapter it should support everything: low, full, and high speed, provided it only draws one unit of power. Is it possible your hard drive draws more than 100ma and caused errors on the line?

 

[jottt]

Hi, here are my observations on the matter OTG-Port (with HF5-RC2):


If you change between host and client device, you need a reboot. The Pandora does not like the swap while running and only detects the type that was plugged in the first time, If you change it, it wont detect anything at all anymore.


Usually, when power is an issue for the OTG-Port, dmesg logs a profile error, provided the device gets at least enough power to get the USB running.


Make sure you have a correct OTG-cable (Pin 4 & 5 at the Pandora plug on ground) if you built the cable yourself.


Keeping an eye on that, there is another issue that might become a problem: Connection is not always detected properly when inserting the Plug to the Pandora. Sometimes I have to replug a couple of times.


BESIDES all those issues...it worked fine for me

 

[Matthias_H]

Got it to run now. Turns out my eBay/China OTG adapter was essentially a plastic hose with USB connectors glued on and no electrical connection whatsoever. What a scam.... With a proper adapter cable, it worked right away.


No more hub needed to hook up my Retrode