I just got and put together my Qualia display—what a beautiful screen. I had an idea about powering the display from my MacBook—would it be possible to get power out of the FireWire port? From the FW spec, it appears that more than sufficient power is available.
This doc: http://firewirestuff.com/techspec800.html shows 12.8V on FW800, and my voltmeter confirms it.
Is 12.8V too far outside the range of the Adafruit board? If so, I suppose I can get a DC to DC converter and step down to 9V?
Qualia 9.7" Display - FireWire Power?
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Please be positive and constructive with your questions and comments.
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Re: Qualia 9.7" Display - FireWire Power?
12.8V is fine, you need about 600mA - its worth a shot!
- jerwood
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Re: Qualia 9.7" Display - FireWire Power?
This totally works! A little sloppy cable surgery, and I can run my Qualia display from my MacBook Pro with no additional power supply or battery.
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Re: Qualia 9.7" Display - FireWire Power?
Can you explain exactly how you did this? I'd REALLY appreciate it.jerwood wrote:This totally works! A little sloppy cable surgery, and I can run my Qualia display from my MacBook Pro with no additional power supply or battery.
- thebearau
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Re: Qualia 9.7" Display - FireWire Power?
Does anyone know what voltage ranges the screen will accept and at what amps? I have a 13" retina macbook so no firewire ports. I'm wondering if the USB3 ports will produce enough power (probably with a voltage step up), they output 5V @ 900mA (4.5W). From Adafruits response above it seems the screen needs 7-8W but I just wanted to confirm. Alternatively I was thinking I could power it from the 5V 2A USB port on the charger battery I always have in my laptop bag.
- thebearau
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Re: Qualia 9.7" Display - FireWire Power?
Grebenots: I think you would want something like this http://ntcdistributing.com/images/CFA-64P-R14large.jpg (or make your own). You want to wire pin 6 (GND) & 8 (positive) off a 9 pin firewire connector (FW800) to a DC power jack and it should power the screen. I should note that I haven't done this yet, and my laptop doesn't have a firewire port. If I have any luck with powering the screen from USB I'll post my solution (still waiting on UPS to get the screen to me here in Aus)
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Re: Qualia 9.7" Display - FireWire Power?
That's good to know. I've been toying with the idea of powering via thunderbolt as well, but I've heard some things about thunderbolt not dishing up power without a software handshake.
Running the entire setup with a single cable would be amazing, but plugging in an extra firewire cable for power is really a non-issue as well.
Running the entire setup with a single cable would be amazing, but plugging in an extra firewire cable for power is really a non-issue as well.
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Re: Qualia 9.7" Display - FireWire Power?
Did you ever get your USB power to work? I came across this similar project, which may prove useful to you. I think you are right about wiring the firewire to the DC jack. I will try this just as soon as I order this.
http://build-its-inprogress.blogspot.co ... art-1.html
http://build-its-inprogress.blogspot.co ... art-1.html
Please be positive and constructive with your questions and comments.