This guy seems to have had some success, with some minor hardware modifications: http://pansenti.wordpress.com/2013/05/27/beaglebone-black-with-two-usb-host-ports-it-can-be-done-but-its-not-easy/
Andrew. On 12 February 2014 20:18, Mahammad <cair...@gmail.com> wrote: > Hi There > > I am too trying to make the mini usb port to work as a host. > > I am trying to scan the expansion port signals it seams like none of the > pins offers direct access to the processor vbus signal. Should I do this > with some software? > > If with software; what time should it work to enable/disable the volt? And > should it listen to the signal all the time or just during the port > initialization stage? > > Best Regards > > Mahammad > > > > > > > > > On Wednesday, August 21, 2013 4:38:47 AM UTC+2, AndrewTaneGlen wrote: >> >> Understood. Thanks for taking the time to clear that up for me. >> >> >> Andy. >> >> On Wednesday, 21 August 2013 14:36:59 UTC+12, Gerald wrote: >>> >>> Yes, that is what I am saying. I did a design where the 5V was always >>> there. It din't work. I had to add a power switch like I did on the BBB >>> design. >>> >>> >>> Gerald >>> >>> >>> On Tue, Aug 20, 2013 at 9:33 PM, AndrewTaneGlen <andrewt...@gmail.com>wrote: >>> >>>> Thanks Gerald, >>>> >>>> That was one thing I was not absolutely clear on. The TRM has the >>>> following passage concerning USB power control: >>>> >>>> "*When any of the USB controllers assumes the role of a host, the USB >>>> is required to supply a 5V power* >>>> *source to an attached device through its VBUS line. In order to >>>> achieve this task, the USB controller* >>>> *requires the use of an external power logic (or charge pump) capable >>>> of sourcing 5V power. A* >>>> *USB_DRVVBUS is used as a control signal to enable/disable this >>>> external power logic to either source or* >>>> *disable power on the VBUS line. The control on the USB_DRVVBUS is >>>> automatic and is handled by the* >>>> *USB controller.*" (AM335X TRM, pg. 1697) >>>> >>>> So are you saying, in addition to the above, that the USB port must be >>>> in control of the VBUS enable - assumedly detecting the voltage as off when >>>> disabled, and on when enabled, with specific timing requirements around >>>> these edges - so that there is no way to simply have the 5V there the whole >>>> time? >>>> >>>> If this is the case I guess there is a chance that I could add some >>>> kind of gpio control through the expansion header to enable/disable the 5V >>>> rail as and when required (or I could just modify the board - but I'm >>>> trying to avoid this and be able to just plug my clean BBB into my horrible >>>> looking base board...) >>>> >>>> >>>> Regards, >>>> Andy. >>>> >>>> On Wednesday, 21 August 2013 14:20:08 UTC+12, Gerald wrote: >>>> >>>>> Like the fact that the processor needs to see the 5V on >>>>> the processor pin when it turns on the 5V? >>>>> >>>>> Take a look at the host port design. Both ports are actually OTG ports >>>>> by design. To make the state machine in the HW function as a host, you >>>>> need >>>>> to make it work like the other OTG port, the one we call the Host port, >>>>> which is configured for host.. >>>>> >>>>> >>>>> Gerald >>>>> >>>>> >>>>> >>>>> On Tue, Aug 20, 2013 at 9:12 PM, AndrewTaneGlen >>>>> <andrewt...@gmail.com>wrote: >>>>> >>>>>> Hi All, >>>>>> >>>>>> I've been playing around with getting the mini-USB pc connector to >>>>>> function as a second USB host (I'm using RCN's Ubuntu, Raring, but I'd >>>>>> assume this would apply to Angstrom as well). There is a post here >>>>>> http://pansenti.wordpress.com/2013/05/27/beaglebone- >>>>>> black-with-two-usb-host-ports-it-can-be-done-but-its-not-easy/ decribing >>>>>> how to do this with some hardware modifications, but looking at the >>>>>> AM335x >>>>>> technical reference manual it looks like I should be able to set USB >>>>>> Port 0 >>>>>> to function as a host through software alone (i.e. without needing to >>>>>> ground the USB ID pin, or to modify anything else on the board). >>>>>> >>>>>> So what I have done so far is modify the 'am33xx.dtsi' file under the >>>>>> 'usb_otg_hs' section, and change the item 'port0-mode = <3>' to >>>>>> 'port0-mode >>>>>> = <1>', which, according to 'am33xx-usb.txt' in the device tree >>>>>> documentation, should force this port to function in Host mode. >>>>>> >>>>>> I then had a look through menu config, in the 'Device Drivers' -> >>>>>> 'USB Support' section and there didn't seem to be anything specifically >>>>>> relating to setting the mode of any particular usb port, so I left all of >>>>>> this unchanged. >>>>>> >>>>>> Upon booting I can see that whereas previously I would get the >>>>>> following wit regards to USB0: >>>>>> >>>>>> musb-hdrc musb-hdrc.0.auto: *** mode=3 >>>>>> >>>>>> I now get >>>>>> >>>>>> musb-hdrc musb-hdrc.0.auto: *** mode=1 >>>>>> >>>>>> This would appear to indicate that my device tree change had been >>>>>> successfully applied, and the initialisation of USB port0 now looks >>>>>> identical to that of port1. whereas previously they were quite different. >>>>>> >>>>>> I then customised my USB cable to have an external 5V feed (wired to >>>>>> SYS_5V on the expansion header) and added a female-female USB A adaptor >>>>>> to >>>>>> give me a host socket. >>>>>> >>>>>> However, it doesn't work. >>>>>> >>>>>> I have checked the power rail and can see 5V on R159 on the bottom of >>>>>> the BBB and I have double checked that the comms wires are the correct >>>>>> polarity, and everything buzzes out as expected. >>>>>> >>>>>> The device boots, and I can SSH into it. Plugging a memory stick into >>>>>> the standard usb host plug causes messages related to detecting and >>>>>> attaching a disk, but when I plug the same disk into the modified >>>>>> connector >>>>>> assembly I get noting at all. >>>>>> >>>>>> Taking out my change to the device tree returns the mini-USB >>>>>> connection to normal functionality, i.e. providing a network connection, >>>>>> so >>>>>> it would appear that the hardware is all still in good working order. >>>>>> >>>>>> So I'm wonder if anyone else has had luck using the USB OTG >>>>>> connection in host mode - without making any hardware modifications to >>>>>> the >>>>>> board? I all looks like it should work, so I'm guessing I've missed >>>>>> something fairly basic. >>>>>> >>>>>> >>>>>> Regards, >>>>>> Andrew Glen. >>>>>> >>>>>> -- >>>>>> For more options, visit http://beagleboard.org/discuss >>>>>> --- >>>>>> You received this message because you are subscribed to the Google >>>>>> Groups "BeagleBoard" group. >>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>> send an email to beagleboard...@googlegroups.com. >>>>>> >>>>>> For more options, visit https://groups.google.com/groups/opt_out. >>>>>> >>>>> >>>>> -- >>>> For more options, visit http://beagleboard.org/discuss >>>> --- >>>> You received this message because you are subscribed to the Google >>>> Groups "BeagleBoard" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to beagleboard...@googlegroups.com. >>>> For more options, visit https://groups.google.com/groups/opt_out. >>>> >>> >>> -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to a topic in the > Google Groups "BeagleBoard" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/beagleboard/Mbaa5tsdfOk/unsubscribe. > To unsubscribe from this group and all its topics, send an email to > beagleboard+unsubscr...@googlegroups.com. > For more options, visit https://groups.google.com/groups/opt_out. > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. 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