How do I tell if my firewire connection is running as 400 or 800?

Question

I have a MacBook Pro with FireWire 800 and a freecom external harddrive that has USB3, FireWire 400 and 800.

I am using a Nikkai FireWire 800 cable that has 800 connector on one end and a 400 connector on the other end. The 800 connector is attached to the MacBook pro and the 400 connector is attached to the freecom drive.

Is there any way to tell what connection has been established? I looked at disk utility and it simply said 'FireWire'.

Is there a command-line tool that would give more information?

If it's 400, I plan to swap the cable for 800 connector at both ends.

Answer 1

Click on the Apple in the extreme upper left hand corner of the display. When the menu comes down, click on "About This Mac". A dialog will appear. At the bottom will be a button called "More Info". Click on it.

A list will come up with all your hardware in the left column. You may need to click on the little triangle to expand the list. When the list expands, click on the "FireWire" entry. A page will fill out on the right with all your FireWire devices. If you have multiple FireWire devices, you'll have to click on the one in the page that opened up to get the right info. It will tell you the current connection speed and the maximum connection speed.

The 800M FireWire is downward compatible with 400M, but you can't turn a 400M device into an 800M device just by switching the cable unless the drive has both 400M and 800M interfaces. You need to find out if the drive REALLY has an 800M interface or whether they just basically took a 400M and "remapped" the wiring so it's compatible with an 800M (like an internal adapter).

Hope this helps