Filed under: Cool tools, Hacks, MacBook Air
MacBook Air USB hacks
TUAW reader Rowan Pope pointed us to this insane MacBook Air hacking post. How many USB ports does the Air support? Apple says just one; this post says up to 7. Apparently, the Air has a few extra live USB port connections built into that thar skinny little computer. How do we know this? Because the guy downloaded developer documentation for the ICH-8 chip, which offers 5 low-speed and 2 high-speed USB controllers.
He popped open his Air and measured the voltage at each pin. He then used a hacked memory key with a modded USB extension cable (with an extra resistor just to be safe). After connecting the memory key to one of the pins, his MacBook Air system log reported a USB error. A few more tests and adjustments later, he actually got his laptop to recognize the drive. In total, he found three working USB connections plus an unused SATA controller.
TUAW is awed. Be sure to check out the other mod on this much-opened Air: a carbon-fiber bottom case. Sleek!

![TUAW [Cafepress]](http://www.blogsmithmedia.com/www.tuaw.com/media/tuaw-cafepress-promo.png)


Reader Comments (Page 1 of 2)
Luigi193 said 11:47AM on 3-21-2008
I think we broke his server....
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Eric said 11:57AM on 3-21-2008
Or you could plug a USB hub into the Air's USB port and turn your brain off about it.
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potato said 2:31PM on 3-21-2008
True, but having multiple USB ports *is* actually useful sometimes. USB can be extended by hubs to theoretically an infinite number of ports, but in the end the bandwidth available to all devices has a hard limit per-controller.
i.e. If you turn 1 USB port from your laptop into 50, they have to share the 480Mbps between all of them.
Whereas if you had second USB port you've essentially doubled the "total available bandwidth" you have. This is useful for people who attach lots of external drives to their machines, or people who do USB TV tuners, as they're very bandwidth-demanding.
ars_workerbee said 3:23PM on 3-21-2008
@potato: are you really jonesing for 5 low-speed ports that bad? whoooo 4Mb/s!
Tom said 12:02AM on 3-23-2008
@ars_workerbee:
Or an extra high-speed port, doubling his effective 480mbps bandwidth to 960mbps.
Poltras said 12:51PM on 3-21-2008
"Tuaw is awed"
I think it's not the first time you put this phrase here, but everytime I get a broken jaw trying to pronounce it.
I don't know why they didn't include more ports in the MBA, but I'm sure they have a good explanation, not unlike "the bay doesn't open if you make it larger" or "it's not nice enough anymore". I'll stick with my MBP anyway :)
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ars_workerbee said 12:51PM on 3-21-2008
I was checking something in System Profiler on my MacBook Air about a week and a half ago and noticed a bunch of extra USB busses. Whoop-dee-doo.
Just another post to pad the post count for the Queen of Non-News
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Luigi193 said 12:56PM on 3-21-2008
I thought it was interesting...
Shadup!
ars_workerbee said 1:15PM on 3-21-2008
@Luigi193
i suppose you were likewise amazed to find out that the PPC mac minis had an unused firewire pinout on the board, too, right?
potato said 2:31PM on 3-21-2008
Actually Luigi, yeah. I'm a gadget freak in both senses - I love playing with them, and I love hacking them. This is definitely an interesting revelation for me.
Ben said 3:55PM on 3-21-2008
I thought it was interesting too, why don't you go write your own blog instead of heckling Erica.
TEG said 1:11PM on 3-21-2008
Now we need someone to do a mod where they add the extra ports either to the side of the computer or on the top (next to the keyboard).
TEG
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ars_workerbee said 1:16PM on 3-21-2008
you haven't seen any of the macbook air disassembly pics, have you? there's no room.
tuaw said 5:33PM on 3-21-2008
My grand scheme is coming together... the next version of the carbon fiber back will have space for an SD card reader that I'll wire internally.
pscs said 7:55PM on 3-21-2008
you're from macrumors :)
tnkgrl said 4:23PM on 3-21-2008
This is great!
I've located (and hijacked) unused internal USB ports in other laptops before (like my Eee - see links below), but doing this on a MacBook Air is pretty awesome - not sure I'd do it to mine...
http://tnkgrl.wordpress.com/2007/11/28/modding-the-asus-701-eee-bluetooth/
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futurepastnow said 6:52PM on 3-21-2008
Interesting. The SATA controller suggests future hard drive plans.
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tuaw said 9:13PM on 3-21-2008
I didn't actually prove there are SATA signals on that connector, but it would make sense because of its location next to the I/O chip. The connector was too hard to probe - I was afraid I might short something out.
- John Maushammer
(p.s. trying to change my username here; sorry about the confusion!)
Dave S said 12:12AM on 3-22-2008
Maybe if the title wasn't so dang promising! Modding your MBAir to do this may be fun - but it doesn't make sense for anyone - ANYONE - out there, if you need that much throughput you bought the wrong machine.
So can we hack the titles? See lifehacker, they do it right.
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mungler said 12:45PM on 3-22-2008
does anyone know if the MacBook Pro has any spare USB headers? I fancy mounting an internal flash drive as a cheapo SSD boot device... ;)
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