USB 1.1 speeds on BBB with 3.14.55 kernel

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kegsys

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Jun 29, 2016, 1:13:36 PM6/29/16
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So I have a need to slow down the USB port on the BBB to 1.1 speeds. But its unclear to me how the USB registers are being configured for 2.0 speeds and OTG negotiation. 
What do I need to change in the Bootloader (u-boot/SPL) or the Linux configuration source files to force it to remain as a usb device at only 1.1 speeds?


Thanks for any suggestions!


Robert Nelson

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Jun 29, 2016, 2:22:08 PM6/29/16
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Plug in a usb 1.1 (only) hub..

https://www.amazon.com/D-Link-DSB-H4-4-Port-USB-1-1/dp/B000023VUL

now every downstream device will be usb 1.1 only..

Regards,

--
Robert Nelson
https://rcn-ee.com/

kegsys

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Jun 29, 2016, 2:39:12 PM6/29/16
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Thanks for the quick response! 

Granted a slow USB hub would work for a single test setup, but is it possible to slow the AM335x USB down permanently to 1.1 speeds?
Presumably something sets the device up for 2.0 speed and the OTG handshaking, can that be forced into slow speed mode?

Cheers,
Keith - kegsys
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