Re: Target Disk Mode not working?

On Sat, 07 Jul 2007 08:27:08 GMT, T i m <news@xxxxxxxxxxxx> wrote:
On Fri, 06 Jul 2007 23:42:31 GMT, Bob Wardrope
<newsbybobwar@xxxxxxxxxxxxxxxxxx> wrote:

I use a firewire bus powered external on my portable and am paranoid
about making sure it's set to take no power from firewire when the cable
is initially plugged into the computer and drive case. I switch it to
firewire power mode after checking both ends of the cable are secure.

I wonder if that's why FW never really 'took off' (as in mass consumer
products sense), a bit like SCSI (in spite of all my boxes having SCSI
kit in them at some point and this PC still has re an Adaptec 2940W,
Zip and OnStream tape drive) and not like USB?

I'm not aware of my external FW enclosure having any 'settings' like
yours Bob and was slightly 'concerned' when I was plugging FW leads
between host and device, host to host, host > device host without
having to use special cables (x-over) etc? Looks like my 'concerns'
weren't without substance and 'hopefully' this exercise hasn't damaged
the Mini (as I now don't have anything else FW to test it against).

No, they're without substance.

Exactly like USB, the FW plug has different length conductors so that
ground then power then data connect. There's no difference between the
two in that respect.

There's no need for crossover cables (or A-B cables) because firewire
is a more general utility bus than USB. USB is designed to connect a
host computer to a subservient device, which is why if you plug two
computers together with an A-A cable the magic blue smoke comes out.
Firewire is an peering bus, which doesn't dictate master/slave
relationships, so all devices are equivalent.

The FW plug is also impossible to plug upside down (which usually
breaks the USB socket), and can supply more power than USB. It's also
better at streaming data constantly than USB, so it's considerably
faster for external hard drives etc.

It's a bit of a BetaMAX syndrome, I reckon. Better, but started out
slightly more expensive and that causes a snowball effect.

All that said - with a bus-powered hard drive Bob's mild paranoia is
sensible: flickering the power up and down while plugging clumsily is
bad for any hard drive, so it's worth avoiding if possible.

Cheers - Jaimie
--
"Every Little Thing She Does Is Sufficiently Advanced Technology"
.

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