Hot-plugging Firewire/Thunderbolt

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Hot-plugging Firewire/Thunderbolt

Hey guys. I have recently bought a bus powered firewire 400 audio interface (Focusrite Safire 14). I am connecting it to my 2014 MBP 15" using a Thunderbolt adapter. I learned once I had bought the interface that firewire is not hot-pluggable and that I might have to shut down my mac each time I want to connect/disconnect the device which is not convenient; http://uk.focusrite.com/answerbase/firewire-safety-when-plugging-and-unplugging- your-firewire-devices

I was just wondering;

1. Does putting mac to sleep definitely shut down all the power to the TB ports? (all the lights on my interface seem to switch off but is there still power being supplied to it?!)

2. Is there any other way to force shut down the Thunderbold ports on a mac (for instance by using Terminal)?

3. Would testing the interface and/or the cable for power using a voltage tester give me a definitive answer? (Will this one work - detects from 90V to 1000V AC; http://goo.gl/OMnygM)

MacBook Pro with Retina display, OS X Yosemite (10.10.1), 2.2 GHz Intel Core i7, 16GB RAM

Posted on May 23, 2015 10:13 AM

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Answer 1

Best reply

Linc Davis

Level 10

209,547 points

May 23, 2015 10:19 AM in response to Jamesedwards

1. Yes.

2. No.

3. There is no need to test. I suggest you get other opinions before relying on the information from "Focusrite," which is not necessarily correct. It sounds to me like they're trying to forestall warranty claims.

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Answer 2

Jamesedwards Author

Level 1

15 points

May 31, 2015 1:38 AM in response to Linc Davis

Hi Link. Many thanks for your reply. Just an update as I have been using the interface a bit more this week;

I have noticed that the interface does actually have a "Power" light on it along with a "FW" (firewire) & "LKD" (locked) light.

When I put the mac to sleep all 3 lights switch off after about 15 seconds. However, when I plug the interface back in again (with mac still supposedly in sleep mode) the lights all light up.

Does this mean that power is still being supplied to the TB ports whilst in Sleep mode? Or, is it that plugging something into the TB ports wakes the system & starts it supplying power to the ports?

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Answer 3

Jamesedwards Author

Level 1

15 points

Jun 12, 2015 10:02 AM in response to Linc Davis

Hi Linc. Just wondering whether you saw my last reply?

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