PCI Expansion Card Question

[Jim Brennan]

Forgive me if I use the wrong terms. I have a MBPro dual 2.2. I went out and got a PCI FW800 Expansion Slot thingie. I've been data wrangling a bit and since the MBPro only has one FW 800, and I often go from one drive to 2 or 3, I thought it would be faster than daisy chaining. But it's not. In fact, it's a lot slower. I figure I must be doing something wrong. I tried to find a way to configure the expansion card (It's a Sonnet Expresscard 34), but came up empty.

Any thoughts?

[GenJerDan]

Shared interrupt? Or other semi-conflict?

[Jim Brennan]

Shared interrupt? Or other semi-conflict?

See, that proves to me that there are a bunch of people on this site with bigger brains than me. I don't even know what that means. :smile:

[GenJerDan]

Actually, not sure if it works the same on a MacBook (not even sure if that's what you have....).

Anyway, an interrupt (also IRQ) can be shared by different devices, whichever being active at the moment grabbing it. If more than one are active,they'll have to alternate its use (not really, but in effect).

If your onboard FW and the new card use the same IRQ, there'll be problems. Likewise if they use the same memory address...

But this is looking from a PC viewpoint and may not apply to a Mac.

However, if you can look at any sort of hardware properties, see if any of the numbers are the same. And if they can be manually changed, if so.