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#10578 - 06/17/10 03:53 PM Looking for 20 foot 9 pin to 9 pin Firewire cable
JoBoy Offline


Registered: 08/05/09
I've looked on Apple's web site, MacConnection & Monster Cable and cannot find a Firewire 800 9-pin to 800 9-pin cable that is 20 feet long. Is there a cable length limit to Firewire that would prohibit such a long cable?
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Mac Pro dual Quad-Core Intel Xeons Early 2008; 16GB RAM; MacOS X 10.11.6, iOS 9.3.5

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#10580 - 06/17/10 04:24 PM Re: Looking for 20 foot 9 pin to 9 pin Firewire cable [Re: JoBoy]
joemikeb Online
Moderator

Registered: 08/04/09
Loc: Fort Worth, Texas
According to this the IEEE 1384 standard limits the cable length to 4.5 Meters or 14.7637795276 feet. That does not mean you cannot go further but if you do you should use a powered repeater.
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#10583 - 06/17/10 05:40 PM Re: Looking for 20 foot 9 pin to 9 pin Firewire cable [Re: joemikeb]
JoBoy Offline


Registered: 08/05/09
OK. I think I saw one cable that is 14 feet long. I'll just have to move one of the computers so I can connect it with my Mac Pro. Disk Warrior STILL doesn't have the bootable operating system for Disk Warror DVDs for the iMac 27" i7 quadcore and I've had that machine for seven months! Alsoft blames Apple. Regardless of who is to blame, I've decided to try putting the iMac in target disk mode and booting from my Mac Pro while the machines are connected by FW800. Hopefully, that setup will enable me to run Disk Warrior on the iMac's internal hard drive. I probably ought to check in with Alsoft to see it there's a hidden land mine in that approach. I already have two DW licenses.

Thanks a lot for the info.


Edited by JoBoy (06/17/10 05:44 PM)
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Mac Pro dual Quad-Core Intel Xeons Early 2008; 16GB RAM; MacOS X 10.11.6, iOS 9.3.5

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#10586 - 06/17/10 07:52 PM Re: Looking for 20 foot 9 pin to 9 pin Firewire ca [Re: JoBoy]
Virtual1 Offline


Registered: 08/04/09
Loc: Iowa
My mom's original imac g5 had an external firewire isight camera. she's got a big loft and a lot of neat stuff there and frequently tried to point the camera to show me something.

So I bought her a 25 ft firewire cable, and a firewire coupler. (yes, they make them) Now she can get up and walk over to it etc.

Works fine for the camera. I suppose you may get slower file copies etc though if it gets errors due to cable length or cumulative interference. Finding said cables and couplers though is a little bit of a trick, but you can obtain them, they're out there. I carry a white isight (6ft) firewire cable in my bag due to its small size and low weight, and I think I've seen it doing slower file copies than a standard cable, but it still works, no refusals, no random disconnects or stalls.

On a related note I've used a whole boxfull of usb cables and extensions to get a usb run on a wireless adapter up and out of a basement up three flights of stairs, and that too worked nicely. So I think it's a "maximum length we GUARANTEE to work is ..." more than a law. Though I do remember back in the days of scsi you most definitely had to be careful with cable lengths.

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#10589 - 06/17/10 08:36 PM Re: Looking for 20 foot 9 pin to 9 pin Firewire ca [Re: Virtual1]
JoBoy Offline


Registered: 08/05/09
Thanks, Virtual1. If I intended to use a longer cable for a lot of stuff, I'd probably try to find one, but, since I'm attempting an experiment to see if I can do Disk Warrior maintenance on an iMac i7 quadcore by putting the iMac in Target Mode and running DW from my Mac Pro and have no other use for the cable, I think I'll stick with a 14 footer.

By the way, do you see any reason why I wouldn't be able to pull that off? I'm trying it because Alsoft still doesn't have a DVD with DW on it that will boot on an iMac i7 quadcore and I've had that machine for nearly seven months. That i7's internal hard drive needs some kind of maintenance since I can't even use Disk Utility on the i7's Install DVD because the i7's slot drive has trashed it and my wife won't give up possession of the i7 long enough to take it to the Apple Store for repair. (she's writing a book and doesn't want down time)
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Mac Pro dual Quad-Core Intel Xeons Early 2008; 16GB RAM; MacOS X 10.11.6, iOS 9.3.5

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#10594 - 06/18/10 06:46 AM Re: Looking for 20 foot 9 pin to 9 pin Firewire ca [Re: JoBoy]
joemikeb Online
Moderator

Registered: 08/04/09
Loc: Fort Worth, Texas
I have done what you are attempting with no problems. However, in the interests of full disclosure I was running TechTool Pro not Diskwarrior and the target machine was not a quad core. In Target Disk Mode the processor on the "target" machine is completely transparent and all the "working" Mac sees is a firewire mounted hard disk drive I see no reason why it should not work even on a quad core. However, it will be a lot slower than it would if you were running directly on the quad core.
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#10595 - 06/18/10 08:25 AM Re: Looking for 20 foot 9 pin to 9 pin Firewire ca [Re: joemikeb]
JoBoy Offline


Registered: 08/05/09
Thank you. That is encouraging. I realize there are no guarantees, but it seems like it may be worth a try. I'll follow up when I've obtained the cable.
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Mac Pro dual Quad-Core Intel Xeons Early 2008; 16GB RAM; MacOS X 10.11.6, iOS 9.3.5

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#10603 - 06/18/10 12:51 PM Re: Looking for 20 foot 9 pin to 9 pin Firewire ca [Re: JoBoy]
Virtual1 Offline


Registered: 08/04/09
Loc: Iowa
I will continue to preach the virtues of having a little portable 2.5" hard drive with firewire and usb interface, with a full bootable installation of 10.5 and 10.6 on separate partitions, with all the tools installed and ready to rock.

My service drive as a dozen partitions on it and is in most cases all that I need to work on a machine. No need for long cables either. Mine's a good deal more complicated than that, but that's probably all you need.
_________________________
I work for the Department of Redundancy Department

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#10612 - 06/18/10 09:44 PM Re: Looking for 20 foot 9 pin to 9 pin Firewire ca [Re: Virtual1]
JoBoy Offline


Registered: 08/05/09
The question in my mind is whether Disk Warrior's problem with the i7 is merely not having Apple system software for booting a DVD on the i7 or whether there is a problem with the Disk Warrior application and the i7 processor. I asked ALSoft's tech help about the technique I intend to use to rebuild the directory on the i7's hard drive and the answer was that utilizing Target Disk Mode to rebuild the directory of a computer's hard drive is just fine.

Rather than use a bootable external hard drive, I can completely avoid the i7 problem by putting the i7 into Target Disk Mode and boot from my Mac Pro that already has the latest DW version installed.
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Mac Pro dual Quad-Core Intel Xeons Early 2008; 16GB RAM; MacOS X 10.11.6, iOS 9.3.5

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#10628 - 06/19/10 12:47 PM Re: Looking for 20 foot 9 pin to 9 pin Firewire ca [Re: JoBoy]
Virtual1 Offline


Registered: 08/04/09
Loc: Iowa
while target mode will work nicely, having a bootable portable HD eliminates the need for a second computer.
_________________________
I work for the Department of Redundancy Department

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#10685 - 06/22/10 03:45 PM Re: Looking for 20 foot 9 pin to 9 pin Firewire ca [Re: Virtual1]
JoBoy Offline


Registered: 08/05/09
I received the 9 pin to 9 pin FireWire 800 cable and accomplished the task in minutes. I was wowed by the speed with which Disk Warrior performed its maintenance on the iMac's internal drive. The cable was easily connected to both machines and the job was performed in about the same time that an external hard drive would have done it. (In my shop, they both connect with the same kind of cable).

Thanks to all for the help.
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Mac Pro dual Quad-Core Intel Xeons Early 2008; 16GB RAM; MacOS X 10.11.6, iOS 9.3.5

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