jason thurber's blog

globally-scoped ramblings

Delkin Cardbus32 + OSX = Kernel Panic

without comments

I ordered a Delkin Cardbus 32 CF adapter last week. This was intended to solve the “what is the smallest device I can use, that doesn’t have any cables hanging off it, that’s still really fast, to copy CF (I/II) cards to my laptop” problem… you know the one I mean. It’s a bit pricey (about 3x the cost of an external USB 2.0 reader), but it’s supposed to be as fast as Firewire or USB 2.0, and the form factor is great.

Yesterday (in anticipation of delivery) I went to download the OSX drivers from Delkin. Bad news, the OSX beta drivers require that you “Shut down the computer and insert the CardBus adapter (with CF Card).” This is a major deal killer. I waited until I got the card this morning and tested. Sure enough, carefully eject the disk, power off the card from the menu, eject it, re-insert it and… voila, kernel-panic and a reboot (which does simplify the “shut down the computer” step, but not in a good way). Here’s what I’ve done to attempt to rectify the problem:

1) Called Delkin support and asked “When will there be a production OSX driver?” He didn’t know, but assured me that they were working on it and he’d email me when it becomes available. I considered returning it, but it’s just one of those cases where I’d end up buying it again when the drivers came out, so why waste shipping…

2) Learned a fair amount about Kernel Extensions in OSX. This is really cool stuff, and I’ve gotten to the point that I understand the problem… and know that I can’t fix it… which is basically a bad but interesting place to be. When you insert the Cardbus 32 card it loads an extension named CF32A.kext (and a “personality” named NinjaSCSI or something, I can’t remember and don’t want to reboot my machine again). If you manually load this extension using kextload it can be unloaded and subsequent reloading/unloading can be performed with no problem. But as soon as you actually insert the card it becomes impossible to unload the extension (using kextunload).

C’mon Delkin… just a little more work and this will be a really cool accessory!

Written by jthurber

March 17th, 2004 at 9:47 am

Posted in review-lite