Trouble

USB problem.

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rozie  
Hi.
Yesterday I got my Banana Pi. I already have RPi in NAS (power goes to active USB hub 2A, where RPi and 2,5" HDD are connected, the other (signal) cable goes from RPi to USB hub), works fine. I grabbed Banana Pi with Raspbian (3.0) and used in the same hardware setup. No boot, all LEDs dark.

Then I disconnected some cables and it booted fine. The problem is: when I connect something on USB,  no matter if this is 2,5" HDD or signal cable to the hub, Banana Pi instantly goes down. All LEDs get dark. But it still draws around 4W (at the electrical outlet).

I suspected short circuit on USB, but when cable alone is plugged, it runs fine. It also works with pendrive connected. So it looks a little bit like power issue (but signal cable to USB hub should not take any power). Power supply seems fine and with Banana (and everything) it takes only around 3-5W at outlet. With RPi and heavy load it took over 7W. The problem seems to be with Banana Pi. Broken hardware? Capacitors? Software? Anybody had such a problem? Any ideas how to debug (it's headless and don't have monitor so cannot check screen output)?

BTW It's hard to reach this forum. My normal IP is 85.221.157.x (medium ISP in Poland). When I try to reach forum from that IP, for example release notes, I got blank page. The same problem have friend of mine (but he's using IPpredator VPN, so OK, it might got blocked). Had to use proxy to get to this forum.
I have happen to the USB problem before. Sometime when I use the usb HUB to connect the 2.5 HDD, the Banana Pi will shutdown. But sometimes when I change another usb HUB it works well.

I have happen to the USB problem before. Sometime when I use the usb HUB to connect the 2.5 HDD, the Banana Pi will shutdown. But sometimes when I change another usb HUB it works well.

I have happen to the USB problem before. Sometime when I use the usb HUB to connect the 2.5 HDD, the Banana Pi will shutdown. But sometimes when I change another usb HUB it works well.

rozie  
Reply 1# rozie

OK, I tested following setup. Bpi powered by phone charger (850 mA), HDD connected to USB hub. At first connection it died, but managed to turn on. And then I managed to disconnect and connect USB plug to bpi without issue. Looks like bpi is very sensitive about power.

You can try some 2A power supply.

rozie  
The USB hub is 2A. Is it possible that RPi and BPi work stable with 500 mA limit? I wonder if there are power cables for Banana Pi/RPi like for HDD's on USB - two USB to computer, one output. To workaround 500 mA limit per USB port...

Raymond  
Reply  rozie

OK, I tested following setup. Bpi powered by phone charger (850 mA), HDD connected to ...
rozie Posted at 2014-7-9 10:58



I checked my BPi booting current without 2.5" HDD connected.  Few points during booting, the current meter hit 700~800mA and then down to 200~220mA stable.  (I use 5V2A adapter from wall.)  
*Booted with SD card + HDMI output:  210~220mA
*Booted with SD card + HDMI output + Ethernet cable connected: 230mA


That means your phone charger works on the critical limit for booting process.  Still recommend you to use 5V2A directly from wall especially you may connect 2.5" HDD which drains power from BPi board).  Good for the HDD health as well.

rozie  
If you use a powered hub 2 to 3 amp then run a USB -A to USB - micro cable from one of the hub usb slots to the Bpi power input.

This is my original setup, described on very beginning (probably not clearly, sorry). If that worked I wouldn't start a thread.

There was a little chance that this is problem with kernel and loading modules, especially that I used secondary SD card, probably with badblocks for test, but it looked rather like electrical issue. Changing power source confirm this theory.

Gonna grab multimeter and look for voltage drops.

ddurdle  
Reply 1# rozie


   I don't know exactly your problem, but I can add my two cents.
The Banana Pi doesn't appear to be backpowering over the two USB ports.  On all my Rpi, I can connect a single host USB cable from either of my two USB hubs (one is a powered monoprice hub, other is a lapdock) to the USB port on either Rpi A or B, and everything works great.  The Pi gets powered, the USB connection is established with the USB hub, etc.

On Banana Pi, there appears to be no back powering.  for lapdock, the Banana Pi doesn't get power and stays off.  On the powered hub, the powered hub stays low power meaning it detects nothing on the USB host, and the Banana Pi remains powered off.  What I need to do is hook up the Banana Pi DC USB or OTG USB to one of the powered ports on the USB dock or lapdock.  Then it turns on and everything works.

So, it appears like the original version 1 of Rpi B that did not back power over USB (which forced you to use Y USB cables or dual USB cables to both mini and regular USB port).

Regarding "losing power", never experienced that problem when using powered USB hubs and 2.5" HDs connected to the powered hub with either Rpi or Banana pi.

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