power issues

[pedley]

OK so I have had my Pi running Raspbmc for a while my set up is.

Pi powered by a 2 amp supply.
Powered hub

Keyboard and mouse into hub

Yesterday I bought myself this remote http://www.maplin.co.uk/media-centre-ir-remote-385365

Plugged it in worked ok for a few min then things started getting roppey.I kept losing network connection after checking routers, cables the lot I have tracked it down to the IR receiver. If I unplug the keyboard and mouse and just leave the IR in the hub all works fine.

I tried the IR direct to the pi with nothing else plugged in and same again drops the network connection.

The hub is powered by a 1.2a supply could it be that the IR Receiver is drawing that power and pulling from the pi as well hence knocking out the ethernet. I wouldn't have thought this possible but it's the only explanation I can come up with.

[Grumpy Mike]

While the power supply is capable of enough current you can't get enough current through the USB. In the Pi it is limited to devices that take less than 100mA. There is a poly fuse protecting it and it looks like as that got warm because you were taking too much current it dropped the voltage on the device sufficiently to make it not work correctly and that upset the software.

The solution is to use a powered hub or short out the poly fuse protection devices.

[pedley]

OK so I have had my Pi running Raspbmc for a while my set up is.

Pi powered by a 2 amp supply.
Powered hub

It is using a powered hub that's what I can't figure

[mahjongg]

Try powering the PI from the hub too, in theory the hubs ports should only provide 500mA which is marginal for the PI, but in most cases the HUB's don't care exactly how much current you pull from a single port. Powering the PI from the hub can solve all kinds of insidious power problems.

[exartemarte]

It solved mine: http://www.raspberrypi.org/phpBB3/viewt ... 13&start=0

[exartemarte]

[...] in theory the hubs ports should only provide 500mA which is marginal for the PI [...]

I've wondered about that. If I remember rightly the Model A needs only around 300mA, and the only difference is the USB ports. Maybe that 700mA figure for the Model B includes an allowance for usb powered devices, such as keyboard, mouse or memory sticks used without a hub. If we only connect such devices to a powered hub then 500mA for the Pi may be perfectly adequate.

[itimpi]

If you do to mind losing two ports on the hub, then you can always use a USB Y cable of the sort that is typically used with 2.5" USB hard disks. This gives you up to 1A which is definitely plenty for the Pi.

[pedley]

Try powering the PI from the hub too, in theory the hubs ports should only provide 500mA which is marginal for the PI, but in most cases the HUB's don't care exactly how much current you pull from a single port. Powering the PI from the hub can solve all kinds of insidious power problems.

I'll give it a try but if the supply that is powering the hub isn't enough to power the peripherals plugged into it then adding another 500mA on to will make it worse surely.

Might need to get a higher rated supply for the hub.