More iPad woes – ‘Cannot Use Device’

Hey iPad Camera Connection Kit Users – been seeing this screen lately?
Cannot Use Device
I wrote in an earlier post back in May of my experiences uploading images from a CF card via the USB connector in the Apple iPad Camera Connection Kit. The card reader I was using at the time was an old USB 1.1 which was contributing to the slow upload speed.


I spoke about this with David Ziser when he was in Houston and he recounted he wasn’t experiencing such slow upload times personally. He suggested I try a card reader from Delkin Devices. I couldn’t find one locally so I ordered one from B&H Photo Video.


I did find that the files uploaded a lot faster – not that I timed it as I had in May – but fast enough for the iPad to serve as a backup (if only it had more memory!). So I was quite annoyed when I went to upload some photos to my iPad last Saturday to see the message above.


I googled CF Card Readers for iPad and found mostly discussion threads. One was a link to a Terry White video showing him using both a Delkin and a Sandisk card reader. I pulled out my Sandisk card reader and got the same ‘Cannot Use Device’ message, so I returned to Chrome and the internet once more. It took a few more searches before I hit pay dirt at ModMyi.com.


When Apple rolled out iOS 4.2 for the iPad, they cut the power output of the 30-pin connector from 100mA down to 20mA. So that’s why the Delkin Devices card reader had worked with my CF cards before, when I was on iOS 3.2. Of course, I don’t want to take the iPad back in OS versions so now my only option to get images from my 5D Mark II or 5D to my iPad is to connect the camera via the USB port and use the power of the camera to transfer the images. But of course, I can’t keep shooting while I’m doing this.

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The theory is that Apple wants to preserve the power – perhaps other features in iOS 4.2 use more power? But I would prefer, rather than Apple deciding for me, that I be given an option through the settings to control the power output of the 30-pin connector. I’m a big boy, I can handle the consequences of my decisions.


In the current issue of Intelligent Life, Robert Lane Greene discusses the clash of Appleism and Googleism. He compares the ‘Steve knows best’ approach of Apple to the ‘throw it out there and see what sticks’ approach of Larry and Sergey (and of course, both approaches have their pros and cons). The beauty of Appleism is that Apple products just work. But Steve achieves this by making all of the dangerous and most of the banal choices for us. Every now and then, it would be nice if Steve would give us more latitude to make our own decisions. Giving us iPad users a choice on the power of the 30-pin connector would be a great place to start!

Richard Davis December 19, 2010
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6 Comments

  3. I am also having the same problems trying to copy some home videos to my iPad. I get the “requires too much power” message. I originally purchased the card connection device via eBay and couldn’t transfer, then was told to get the proper Apple connection devices for the SD card and the USB connections, which I did, and they still don’t work.

    With my LAY brain on these things,,…..how do I get the videos to the iPad? I tried copying one jpg picture and got the same message so it wasn’t necessarily the size that was too much.

    I am at a loss how to achieve this. If anyone can help me further I would love to hear from you. I have the origianl iPad with version 4.2 and know/knew nothing about the power outlet and 30 pin xxxxxxx – its all double dutch to me.

    Vicki

    • Hi Vicki,

      If you’re still getting the “requires too much power” error with the apple SD card reader then I think the only safe way out is to connect the USB connector to your iPad and then use a USB cable to connect your camera to the apple USB connector and use the power of the camera to push the file to the iPad rather than relying on the power of the iPad to pull the file in from the card. Does this make sense to you? Only downside is that while the camera is connected to your iPad you can’t really use it to take more pictures/videos.

  4. Hi Albert,

    I just got back from Florida, read your comment, and did some investigating. I’ll blog the results of that later in the week but it seems that my success is due to my card reader (see the Gear section in my Bookstore (http://astore.amazon.com/richarddavisp-20)

    This reader, alone among all my CF car readers, will read a CF card to my iPad running iOS Version 4.3 (8F190). What’s more intriguing is that this card reader will also allow an series one iPad running iOS 4.2.1 (8C148) to read photos off a CF card.

    Also now, both the above iOS versions will read SD cards.

    If you connect your 7D via a USB cable from the micro-USB on the camera to a standard USB on the iPad camera connector kit USB connector, turn the camera on and plug the camera connector into the iPad port, then the iPad will be read the images off the card. In this scenario, the power for the transfer is being provided by the 7D, not the iPad.

  5. Well, I reached this article for the same issue. But honestly, the most interesting part is your tweet, which i accidentally read while reading this article!
    At the same time, I can see this http://discussions.apple.com/thread.jspa?messageID=13203099 says they haven’t fixed anything yet.
    So, could you please give us more details? Did they really fix it or you just tried couple of new things?

    1 more thing, if I am going to use the camera USB cable all the time, would that really work without a problem with the iPad? using canon 7D, or sometimes Sony alpha200 ?