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fompsweeva
19th April 2005, 05:23 PM
Hey there,

I'm getting a canopus and I realised I only have one firewire plug on my powerbook, so I assume I can only use either my external drive or the canopus at any given time, not both.

However, then I realised Firewire is daisychainable. Would it be safe/reliable/bareable to run a canopus (used to capture) and a firewire hard drive together?

Cheers
-Mike

gaehl
19th April 2005, 06:12 PM
This Really isn't a Laptop specific question moving to "Hardware General".

That being said depending on the bandwidth requirements of the Canopus it should be fine.

hawker
19th April 2005, 06:34 PM
My first firewire hard drive, which was a big arse 60GB, had two firewire ports, and I could actually plug the hard drive into my iMac, and then plug a firewire mini dv camera into the other firewire port on the back of the firewire hard drive. Was heaps good :)

Daisy channing usually only works if you plug the thing that needs the most power in first and then go down the line.

Currawong
19th April 2005, 06:40 PM
There's nothing stopping you running HD's, canopus box, and TCP/IP over firewire on one chain (I've done it, didn't break anything). Mind you, power requirements, as hawker suggested, might get in the way, as well as outdated firmware on drives, and the odd weird device conflict caused by firewire really being serialised SCSI.

zbaron
19th April 2005, 08:37 PM
Also watch out for firewire's QoS features. Some devices will request an allocation of guaranteed bandwidth, reducing what is left on the bus for other devices. iSights do this and i've been caught cursing a "slow" hard drive, until I unplugged the iSight and got the hard drive back up to speed.

Jimbo
19th April 2005, 09:18 PM
just remember the canopus will use 100mbits of your 400mbits bandwidth, and your HD will use whatever the canopus is using, so you're using 200mbits of bandwidth. plus it may only work in single duplex mode, as the info (assuming you're capturing to your external HD) will have to travel from the canopus, to the computer, be decoded, then encoded, then back up the fire-wire to the drive, every bit needs to travel this way. This may increas errors, but i've NEVER had a problem doing what you've mentioned, even with the ADC-500, which is used for Hi-Def capturing...

That said make sure your cables are good, and short, and you shouldn't have any problems.


-Jim

Donnie-Darko
19th April 2005, 10:06 PM
I can highly recommend thes enclosures

http://epowermac.com.au/product.asp?P_ID=117

2X firewire 800
1Xfirewire
1Xusb2

surely it must help to daisy chaiun firewire though firewire800 to start with ?

anyway, good luck with your setup

hawker
19th April 2005, 10:26 PM
Originally posted by Donnie-Darko@Apr 19 2005, 10:06 PM
surely it must help to daisy chaiun firewire though firewire800 to start with ?
It can't hurt. The reason it is fine to hook up a firewire external hard drive and then a mini dv camera to the external hard drive, is because, the hard drive usually needs six to six pin, ie getting power from the computer, but a camera is six to four pin and does not require any power. Coupling up hard drives could have some issues.

if you want say two firewire hard drives, you may wish to look into the new firewire 800 racks that can conain two hard drives within. Neat idea.

LCGuy
20th April 2005, 12:19 PM
I'm not sure about FW800, but wasn't FW400 originally designed to be daisy-chained?