Daisy Chaining USB?

Discussion in 'MacBook Pro' started by GuitarDTO, Mar 12, 2011.

  1. GuitarDTO macrumors 6502a

    Feb 16, 2011
    New MBP owner here, my setup includes a 27" cinema display, a numeric keyboard hooked up through the monitor, and I also use an Apogee ONE interface. Today, I had the APogee hooked up through the USB port on the keyboard (So thats MBP==>Monitor==>Keyboard==>Apogee). I noticed right away static and crackling when listening to headphones through the Apogee. Plugging it straight into the MBP made it all go away. Then, I plugged an external harddrive into the keyboard as well, so thats MBP==>Monitor==>Keyboard==>HDD, and I got an error saying insufficient power was available so one of my USB devices were being shut down.

    Now, it seems obvious, but is this a common thing that you can't have too many USB devices connected, or is the issue more with daisy chaining them? It would be nice to not have to worry about it because between the monitor and MBP, thats only 4 available USB ports if I dont include the 2 on the keyboard which seem useless. Just curious if others have experienced this.

  2. gullySn0wCat macrumors 6502

    Dec 7, 2010
    The keyboard USB ports aren't self-powered, which is the problem. You can get a powered USB hub, or just use the ports on your ACD and MBP.:)
  3. snberk103 macrumors 603

    Oct 22, 2007
    An Island in the Salish Sea
    The keyboard USB ports aren't that useful. You will be amazed by what doesn't work there. I use mine for my mouse, and use hubs off the box or the display for everything else. Even some thumb-drives will give you the insufficient power error. I haven't tried a powered hub off of the keyboard yet, but I like my desktop clear, and put all the USB cruft on shelf above the monitor and connected to that.

    Welcome Mac World...
  4. GuitarDTO thread starter macrumors 6502a

    Feb 16, 2011
    Thanks guys, makes sense about the self powered thing. Everything coming off the cinema display seems ok like you said because it has a power source. I guess the keyboard is just useless for the USB slots but oh well. If I find myself needing more USB ports I'll get one of those powered hubs. This will definitely become an issue when I start leaving ~2 external HDD's hooked up to the ACD at all times for photo use. Right now I'm storing my photos on the internal harddrive but at some point I plan to convert them all to an External, and then have another external as backup. I'll need another good USB port.
  5. Manacit macrumors member


    Feb 19, 2011
    New York, NY
    If you can wait for thunderbolt drives, you can chain your display and the two harddrives using only your thunderbolt port.
  6. GuitarDTO thread starter macrumors 6502a

    Feb 16, 2011
    Oooh I keep forgetting about the o'l thunderbolt port. Good point....that changes everything potentially. I probably can leave my photos on the MBP drive for now and use my 1 external HDD as the backup until thunderbolt drives come out. Plus, it'll be faster then right?
  7. gullySn0wCat macrumors 6502

    Dec 7, 2010
    Yep, they are pretty much only useful for things that don't need their own power (eg speakers connected to external, mice...) Apple should be ashamed that they advertise them on the box (iMac with "5" USB ports!:rolleyes:)

    @OP Thunderbolt is faster than the internal interface even SSD use to connect, so it will be like having an extra internal drive. I can't wait !!!
  8. grahamnp macrumors 6502a

    Jun 4, 2008
    Is the keyboard the Apple one with a usb port on the side? I've had the power issues you've mentioned by just plugging in a thumbdrive so I think the keyboard is the culprit in your situation. I believe that the only limitation to USB connectivity is bandwidth and the length of the connection, assuming that your equipment is up to spec.
  9. gullySn0wCat macrumors 6502

    Dec 7, 2010
    Yep, I think the problem is that the keyboard draws power for itself, leaving no room over the USB connection for anything that requires more than a tiny amount of power.
  10. jim4spam macrumors member

    Jun 14, 2009
    I've a 24" 2007 iMac which came with the 'new' flat style keyboard. Older (e.g. 2year old) usb bus powered 2.5" external drives don't work due to lack of power, but I newer ones work fine and USB sticks work with no issue.
  11. GuitarDTO thread starter macrumors 6502a

    Feb 16, 2011
    Yeah, this is pretty much going to be my only use for it, a USB stick for swapping stuff to and from my wife's computer on occasion.

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