Firewire 400/800 connectors

[Goi]

Hi,

I'm looking at FW400/800 external HDDs and I'm confused about their connectors, especially the FW800 ones. Usually they'll have 4 connectors(1 6pin, 1 9pin), but some of them have 2 of the same. I'm wondering what the PC side looks like. I tried googling around and found that most if not all Macs use 6pin for FW400 and 9pin for FW800, but my PC only has the 6pin ports. Then there's the issue of Windows support for FW800 at all.

Can someone clear this up for me? Does FW400 require the 6pin connector or will the 9pin connector also do? Same question for FW800. Also what about power? I've read that the 4pin mini connector doesn't have power and the 6pin does. What about the 9pin?

TIA.

 

[Goi]

anyone?

 

[Zepper]

You can use your fave search engine to find- Firewire connectors -and come up with the pinouts for each type of connector. Here is but one of the hits I got:
http://www.interfacebus.com/De...nector_Firewire.html#b

.bh.

 

[AsianriceX]

FW400 comes in 2 flavors, 4-pin (unpowered) and 6-pin (powered).
AFAIK, FW800 only comes as a 9-pin (powered) port. I haven't encountered any mini unpowered FW800 devices.

You can get FW800 9-pin to FW400 6-pin cables, and your devices will run at FW400.

 

[Goi]

So basically FW800 requires the extra 3 pins?

 

[AsianriceX]

Originally posted by: Goi
So basically FW800 requires the extra 3 pins?

Yes. From what I've gleaned from a Texas Instruments document, 2 of the extra pins are for "signal integrity" and the 3rd is reserved for future use. I'm assuming the 2 extra pins provide extra shielding against stray EM emissions that could corrupt the data stream when it's running at high speeds.

 

[Goi]

Thanks AsianriceX. I guess most PC users are screwed with FW800 then.

 

[AsianriceX]

You can always get a FW800 PCI card. I'm not sure if they have PCI-e cards.

The only thing you have to watch out for is a driver problem with XP SP2 and above. I don't remember all the details, but the Microsoft driver would cause FW800 devices to throttle down to S100 or S200 speeds. The fix was to replace the specific 1394 driver files (normally provided on CD with the card) with the pre-SP2 versions through some trickery and circumventing Windows File Protection.

I have no idea if they fixed this in SP3 or with Vista.