Usb 2.0 File Transfer Errors...

altaylor

Registered
I have a high level of mac expertise.

This is frustrating as I am having trouble with file transfers using USB 2.0 on two different macs. The first mac is a Powerbook G4 Titanium 667. The other mac is a desktop Dual 500 G4. Since neither mac has USB 2.0 natively available, I added a SIIG PCI card to the desktop and now have Firewire 800/USB 2.0 available out the back of the mac. I am using an IOGear cardbus card with two USB 2.0 ports in the Powerbook.

USB 2.0 seems to work fine except when transferring files from compact flash cards to either attached mac. The CF card mounts up on the desktop like a digital hard drive and I can open and display the files on the drive, but both macs will stall during an attempt to copy files to the desktop and they never recover. I have to reboot the mac in order to retry the file copy.

I have tried several card readers and USB 2.0 cables, but all fail by stalling out on an image file during the copying process. I can remove the card reader and attach the camera via a USB 2.0 cable and use it as a card reader. Then I insert the CF card into the camera, and the files copy fine... no stalls.

I suspect this is an operating system issue, but need help solving it.

Thanks in advance!
 
There is no such thing as a USB 2.0 cable. USB 1.1 and USB 2.0 use the same cables. Now for your problem: Is your camera USB 2.0 or USB 1.1? As you know, your computer does not support USB out of the box. Did you install USB 2.0 drivers with your SIIG card? I am willing to be corrected, but I don't think that your stock OS installation will support USB 2.0 without drivers. Since I don't see any support for the Mac on the SIIG website, I have a feeling that your pretty new cards are running as USB 1.1, which is supported by Apple for your computers.
 
I know that I had seen somewhere on the forum that some of the older G4 Macs don't have enough power coming through the USB port to power some devices. This might be the issue you are having.
 
Thanks MisterMe and nixgeek... Wasn't aware that there isn't a 2.0 rated cable. Thanks!
Some answers to specific points raised in your feedback:
1. Camera is a Nikon D2X and is fully USB 2.0.
2. I am running OS X 10.3.9 in both macs. All documentation from both 3rd party manufacturers point out that Apple provides native 2.0 drivers in 10.3.x and that there is no need to try to install their drivers. (Those drivers are for windows anyway.) Both list on their packaging that they are fully mac compatible and that USB 2.0 requires OS X 10.3.x or better.
3. USB 2.0 is running fine through both macs except for the lock up experienced during file copy from an external camera card (this happens to different files and on different Compact Flash cards.)
4. The USB 2.0 specs require that 500 mA be present on each 2.0 port. The SIIG card in the desktop mac came with a "Y" power cable and instructions to install it in order to make sure that enough power is available to its various ports.In the laptop I supplement power to the PC card with an AC power adapter (the mfr spec says that such an adapter needs to provide 5 volts DC at 2.3 amps. The one I bought does.)

I think I have eliminated power from the equation, and have tried enough other activities through the USB ports to eliminate the other possibilities outside of the file copy operations from card readers.

Again, all CF camera cards run at 2.0 speed in our two macs, except for file copy operations where they choke on a file somewhere in the transfer (USB 2.0 is fast. In our experience, what takes 15 minutes to copy through a "1.1" port only takes 2.0+ minutes to transfer using USB 2.0. For example, I can open files in Adobe Photoshop CS2 directly from the CF card, I can put the card back into the camera and file copy them from there with no stalling.

Thanks again to everyone who is helping me solve this one.
 
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