Hello everybody, After I and my colleagues had fruitlessly tried many things, our hardware developer came up with a working solution: delaying the PHY initialization performed by the U-Boot we use (v2014.10, git checksum c43fd23cf619856b0763a64a6a3bcf3663058c49). This ensured that U-Boot code tried to access LAN8710A only after this chip had come out of reset. So, inserting "udelay(1000000);" at the beginning of "board_eth_init()" function in board/ti/am335x/board.c and recompiling U-Boot worked in our experiments.
We haven't yet done many experiments, but at least the board, whose PHY failed almost every time before, always starts successfully now. I would appreciate if you repeat this experiment with the delayed PHY initialization and report the results here. I guess the problem was, as described in the reply from Texas Instruments mentioned by Micka <https://groups.google.com/d/msg/beagleboard/9mctrG26Mc8/2aova_Jd__EJ> (I misunderstood that earlier), that LAN8710A starts to function correctly at a slightly higher voltage level than the microprocessor, and may come out of reset too late with respect to the microprocessor. This agrees with the observation that a higher capacity on nRESET_INOUT only worsens things, because it makes the slope of the reset pulse more flat, thus increasing the time lag between the starts of the two chips. @ c2h2: Thank you for your reply. As far as I understand, you delayed the reset of the microprocessor with respect to the reset of LAN8710A by means of some RC circuit, right? If this is correct, could you please provide more details about that circuit? @ Vince Caldeira: Could you please explain, why you marked the topic as complete? If you know any better solution of the problem, please share that with us. Regards, Alex On Tuesday, December 30, 2014 at 2:37:25 PM UTC+1, Christopher and Christina Myers wrote: > > Based on all the comments and discussions I've seen before and after > purchasing my BBB, I'm sure someone will figure out how to fix the issue. > However, unfortunately my knowledge isn't that advanced yet, so while I can > understand what folks are saying (usually,) I'm not at the level to be able > to figure this out :/ It does sound like folks have fixes in the works > though. > > OOC, have you tried any other OSes to see if the problems with your board > persist? I know openSuSE has one as well, but not necessarily support for > all the GPIO built-in. > > On Friday, December 26, 2014, John Tucker <ars_...@windstream.net > <javascript:>> wrote: > >> As I continue to struggle with this problem and asking myself if I wasted >> my money on a product that is not working as advertised, I was wondering if >> it is possible to reset the ethernet interface on the board after the OS >> has booted, either via a script or some other means. Anyone try this at >> all? I'm not ready to give up but this board should work with an ethernet >> cable. >> >> For what it is worth, my pcDuino3 works flawlessly compared to the >> BeagleBone Black. So I hope the people who make the BBB make this right for >> all of us who have purchased this product and have been dissappointed. >> >> John >> >> >> >> On Wednesday, December 24, 2014 3:18:11 PM UTC-5, John Tucker wrote: >>> >>> Thanks for the suggestions. I reflashed the eMMC today with a very >>> recent version of Debian (12/19). This version appears to be reasonably >>> stable. But after rebooting and trying your suggestion, Ethernet was still >>> not available. I even tried booting without an Ethernet cable installed and >>> then plugged it in. Nothing. But what I do see now is the green LED >>> flashing quite a bit. So there is something going on but I never seen any >>> flashing from the Orange/Yellow LED. I can connect to a static IP address >>> but can't seem to get any bi-directional communication. I open a browser >>> and try to go to a website but all I can see is the "Resolving host" >>> message in the browser telling me that something is not just right. After >>> trying to use Putty with no success, my guess is that the BBB is not >>> getting any incoming packets at all. >>> >>> I'm open to other suggestions. I want to use the BBB for ADS-B receiving >>> with an RTL-SDR. I can use a wireless dongle if I have to. >>> >>> Thanks. >>> John >>> >>> On Tuesday, December 23, 2014 2:26:24 AM UTC-5, Christopher and >>> Christina Myers wrote: >>>> >>>> Try my solution a couple of posts up - basically, just hit the reset >>>> button on the board with the board booted and Ethernet plugged in. >>>> >>>> >>>> >>>> On Monday, December 22, 2014, Micka <micka...@gmail.com> wrote: >>>> >>>>> reboot multiple time and try to get the orange Led ! >>>>> >>>>> Le Mon Dec 22 2014 at 14:44:00, <ars_n8...@windstream.net> a écrit : >>>>> >>>>>> I just purchased a Beaglebone Black Revision C and I appear to be >>>>>> having this problem. I can't even use the ethernet port but my wireless >>>>>> dongle works just fine. Has any progress been made to resolve this >>>>>> problem? >>>>>> I can use WiFi for now but I prefer to use ethernet. >>>>>> >>>>>> Thanks. >>>>>> John >>>>>> >>>>>> -- >>>>>> 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+unsubscr...@googlegroups.com. >>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>> >>>>> -- >>>>> 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/9mctrG26Mc8/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/d/optout. >>>>> >>>> -- 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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