Hello, I am planning to use this setup, Have you successfully implemented and completed tests ?
Regards Le vendredi 17 novembre 2017 13:11:59 UTC-5, [email protected] a écrit : > Graham -- > > Thanks for the advice! That totally makes sense. I now intend to try this > configuration to get the added USB1 working in host mode (e.g., to control > a Sony camera using the gphoto2 library): > > > <https://lh3.googleusercontent.com/-lu0aOUP8tbc/Wg8Z3vezBxI/AAAAAAAAAUQ/ud2QXK4zW9gwIhrqVif5ChtTqCcqjDicQCLcBGAs/s1600/PocketBeagle_microUSB_3.png> > > These USB power switch ICs (e.g., Diodes Incorporated AP2822AKATR-G1, Richtek > RT9711CGB, > Richtek RT9742JNGV) limit current, prevent reverse current, etc., and > cost less than a dollar. I'll report back about whether this ends up > working okay. > > -- Will > > > On Thursday, November 16, 2017 at 5:10:48 PM UTC-7, Graham wrote: >> >> Your first connection does not work, because you are trying to power the >> USB1 from the USB_VIN, but since the is no power going into USB_VIN on >> USB-0, there is no power to come out USB-1. >> This only works when the board is powered from USB-0 >> The schematic does not tell you, but USB_VIN, USB0_VIN and USB1_VIN are >> all connected together. >> >> VIN is a totally separate power supply input >> >> Since you are powering the board from VIN (P1-01) you need to hook the 5V >> line on your Micro-USB board to P1-01 and P1-05. >> >> In this case, it will work, although you have no current limit protection >> from a short on the 5V line in a downstream USB device, which is required >> by the USB spec. >> So, only plug in USB devices and cables you trust. >> >> I would not power the USB-5V-VBUS from the SYS-VOUT, because SYS-VOUT is >> limited to 0.2 A or so, and many USB devices draw more current than this >> (USB-2 devices are allowed to draw up to 0.9 A) >> >> --- Graham >> >> == >> >> On Thursday, November 16, 2017 at 5:11:52 PM UTC-6, [email protected] >> wrote: >>> >>> I, too, am wondering about the best way to provide power to the board >>> and to a device connected to USB1 as host. Here is how I learned to hook up >>> a micro-b breakout to USB1 and also how I intend to provide power to the >>> board. The problem is that there is no measured voltage at USB1: >>> >>> >>> <https://lh3.googleusercontent.com/-XyHjxbobnnY/Wg3xGzyvNcI/AAAAAAAAATo/u1ufBwtum9c4KA6T6zjnu38x4cwwQ3TNQCLcBGAs/s1600/PocketBeagle_microUSB_1.png> >>> >>> I was wondering if I could just power the USB1 device from P1_24 SYS >>> VOUT (which does have power when board is supplied by P1_01 SYS VIN) like >>> this: >>> >>> >>> <https://lh3.googleusercontent.com/-l4RYr7WmaGU/Wg3xqYECajI/AAAAAAAAATw/ipK3CZmhG18cieC-bnMLV04PfPBl_hRRACLcBGAs/s1600/PocketBeagle_microUSB_2.png> >>> Would it be harmful to do it this way? Are there better ways to >>> accomplish this? Thanks! >>> >>> -- Will Bain >>> >>> >>> On Sunday, November 5, 2017 at 6:59:39 PM UTC-7, Graham wrote: >>>> >>>> Further research, looking at the Eagle board and schematic files for >>>> the PB, it appears that USB0.VIN and USB1.VIN are both directly connected >>>> to VIN.USB >>>> Which explains why I had no power on my USB1 host port when connected >>>> like the Fritzing diagram, since I am powering from VIN currently. >>>> >>>> So the question becomes,,, >>>> What is the best way to power USB1 VBUS as a host if I don't know in >>>> advance whether the customer application will run from VIN or VIN.USB? >>>> >>>> --- Graham >>>> >>>> == >>>> >>>> On Sunday, November 5, 2017 at 6:58:06 PM UTC-6, Graham wrote: >>>>> >>>>> I note that there is a PocketBeagle pin P1-7 named USB1-VIN. >>>>> >>>>> I don't find any connection on the PB schematic, other than to P1-7. >>>>> >>>>> It was connected externally in all of the USB1 host discussions and >>>>> Fritzing diagrams. >>>>> >>>>> The name would imply that it is a way to deliver power to the board >>>>> when USB1 has an external 5 Volt power source. >>>>> >>>>> I guess the basic question is whether this needs to be used/connected >>>>> when USB1 is functioning as a host. >>>>> >>>>> --- Graham >>>>> >>>>> == >>>>> >>>> -- 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 [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/d3044b29-28b0-4b78-8dbd-5fe7d845206a%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
