I have seen front usb ports that use very poor wiring/board layout. (some that just don't work they are so badly designed)
sam On 07/25/2014 08:31 PM, Gene Heskett wrote: > On Friday 25 July 2014 15:42:23 Gene Heskett did opine > And Gene did reply: >> On Friday 25 July 2014 07:50:25 Ed Nisley did opine >> >> And Gene did reply: >>> On 07/24/2014 09:06 PM, Gene Heskett wrote: >>>> the real problem that caused the usb disconnect? >>> If the dmesg dump says something like: >>> hub 1-0:1.0: port 2 disabled by hub (EMI?), re-enabling... >> Its not saying exactly that Ed. >> Jul 24 20:30:04 shop kernel: [ 762.082869] usb 1-6: USB disconnect, >> address 3 Jul 24 20:30:04 shop kernel: [ 762.340067] usb 1-6: new >> high speed USB device using ehci_hcd and address 4 Jul 24 20:30:05 >> shop kernel: [ 762.800062] usb 4-2: new full speed USB device using >> uhci_hcd and address 3 Jul 24 20:30:05 shop kernel: [ 763.360812] usb >> 4-2: not running at top speed; connect to a high speed hub Jul 24 >> 20:30:05 shop kernel: [ 763.450170] usb 4-2: configuration #1 chosen >> from 1 choice Jul 24 20:30:05 shop kernel: [ 763.459947] uvcvideo: >> Found UVC 1.00 device USB 2.0 PC Camera (058f:5608) Jul 24 20:30:06 >> shop kernel: [ 763.465178] input: USB 2.0 PC Camera as >> /devices/pci0000:00/0000:00:1d.2/usb4/4-2/4-2:1.0/input/input7 >> >> I will move it to a rear panel usb socket just for S&G. Currently >> plugged into a front panel socket, which may or may not be clean >> enough for a high speed connection. The FP socket may not be as >> directly grounded as a rear panel socket could be. The front panel is >> of course a plastic casting so any ground is 8" of breakout cable away >> on the rear of the motherboard. >> >> The camera itself is grounded thru its alignment adjusting screws, to >> the frame of the machine. It also is grounded, but likely not well >> enough. All food for thought, and inspection with my 100mhz dual trace >> scope. I do recall having to put both a capacitor, and a small >> debounce (3 base_thread intervals IIRC) in the "probe" facility on it. >> >>> Then I'll lay you long odds it really *is* EMI from your myriad >>> steppers and suchlike. Spent quite a while figuring that out, but in >>> my case it was an acrylic jacket: >>> >>> http://softsolder.com/2009/01/28/usb-disconnects-nobody-moves-nobody- >>> ge ts-hurt/ >> Sounds like you need a heat leak into the basement, and a humidifier >> installed in the furnace. I have both in the house, but only electric >> heat in the shop and wall fans, for overtemps where all this is taking >> place even when its pouring it out of one of those famous boots. :) >> >> That high humidity failure points to EMI also. >> >>> Now, if that's not what dmesg says, I'd still suspect EMI... >> Thanks Ed. >> >> Cheers, Gene Heskett > I looked at the noise, and other than about 1.3 volts P-P of 60 hz hum > with perhaps 100 millivolts of stepper driver hash superimposed when it > was completely unplugged, nothing of note. An lsusb suggested that the > front panel plugs were usb 1.1 only, so I moved it to one of the rear > panel plugs directly on the D-525-MW motherboard, On reboot it was > correctly linked to /dev/video0, and it ran solidly for about 3 hours > while I finished cutting out the brass makings for the new X screw cover > on my lathe, not a single burp in that 3 hours. > > I think it wasn't 100% compatible with a usb-1.1 port. > > Cheers, Gene Heskett ------------------------------------------------------------------------------ Want fast and easy access to all the code in your enterprise? Index and search up to 200,000 lines of code with a free copy of Black Duck Code Sight - the same software that powers the world's largest code search on Ohloh, the Black Duck Open Hub! Try it now. http://p.sf.net/sfu/bds _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
