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Hardware Hackers Reveal Apple's Charger Secrets
ptorrone writes "In this 7-minute video we explore the mysteries of Apple device charging. Usually, device makers need to sign a confidentially agreement with Apple if they want to say their charger 'works with iPhone / iPod,' and they're not allowed to talk about how the insides work. If you don't put these secret resistors on the data lines too, you get the dreaded Charging is not supported with this accessory. We demonstrate how anyone can make their own chargers that work with iPhone 4, 3Gs, etc."
Resistance is Futile
Lots of companies do this. APC puts a RS-232 serial port on a UPS but wait! They move the pins around so you need a special cable. Cisco used to have a product called the Gigastack that used a standard 6-pin Firewire cable, but no! Pins 1&2 were shorted in the "special" cables Cisco provided.
this is my sig
"She's certainly well-geeky, but 'hot' she's not ;-)"
Nonsense! She has all the characteristics of hotness:
Airway.
Breathing.
Circulation.
"This post is an artistic work of fiction and falsehood. Only a fool would take anything posted here as fact."
Want to cry into your underwear with nerdlust?
Read an article from http://badphysics.wordpress.com/, spend a few futile minutes googling for more pictures and trying to internally reconcile her ravishing looks with such effortless eloquence and boundless intelligence, and then fall even deeper into self-loathing despair with the realization that even your hypothetical best version of yourself wouldn't be good enough for her.
Or, you know, don't. But you get my point. Hopefully, because I don't.
Not only does she have a well stocked desk, she has her own company and sells some geeky stuff to us tinkerers: http://adafruit.com/ Her monochron pong playing clock was featured on /. a while back.
"Something's wrong with you...and I hope we never do meet again." - Deftones When Girls Telephone Boys
i hate when manufacturers do crap like this to keep peripherals locked into a more profitable licensing agreement. Apples tendency toward total control is one of the things i don't like about them.
tho other manufacturers are just as bad. i will never buy a Dell for my home for the same reasons. at work we had an Out of warranty gx 270 desktop. they were know for their bad capacitors in the power supply. so lo and behold the PS goes out. i have to spec a new one. at first i thought i would hop down to the local PC store and grabe a cheap PS for like $30 would work fine.
found out that the motherboards on those dells had different pin layouts from regular boards. the connector was the same as your usual PS but the lines were scrambled. if you plugged in a PS from the PC store you would fry the mobo. thus i would have to get a new PS from the dell store at a cost of $115 ..
we opted for a used PS from a 3rd party supplier for $30 instead.
wish companies would back off and be more open. the way things seem to go we're heaed back to the old at&t days when it took a court action just to add a funnel to your telephone handset http://en.wikipedia.org/wiki/Hush-A-Phone/
But the shown resistors don't look like the standard micro-USB connector. So is Apple breaking it's prommisses? Or am I missing something?
Doesn't it just use micro USB like all the other new phones?
I thought that the EU had forced all of the cell phone makers to adopt micro USB for charging and that they had complied by adopting the standard everywhere (not just in the EU).
I probably don't need to make this point here on /., but I think this is a great development. The convenience and cost saving to me as a consumer are substantial.
Has Apple managed to avoid this?
Do you even have to ask? Yes, we should have a right to repair, and a right to build interface devices.
People often talk about how wasteful Americans are and the problems of a throw-away society. If people were more willing to repair their devices, especially complex electronic devices (most of which fail because of simple and repairable problems, like a broken lead), we would be better off. Aside from less electronics in landfills (let's face it, few people actually dispose of electronics properly), people would not be spending their money so quickly, and presumable that would mean fewer debt problems (or they might just spend it elsewhere).
Of course, we will never see anyone other than a few activists pushing this sort of mentality -- corporations have enjoyed ever larger profits because people are unwilling and unable to repair their own equipment (or to find a local repairman to do it for them).
Palm trees and 8
I'm still trying to figure out if you're talking about catching her on a day with low self-esteem... or rape.
Airway.
Breathing.
Circulation.
Dick? (checks) Nope. Houston we're ready for liftoff.
"I disapprove of what you say, but I will defend to the death your right to say it." - historian Evelyn Beatrice Hall
>>>but 'hot' she's not
Come here sonny. I want to give a brief talk. I recently went to my 15th reunion, and you know those "hot" girls in my class? Well they ain't hot no more! In fact they were downright repulsive (sorry, but it was true). So might as well go for the brainy, geeky girl because that will last. The beauty won't.
If you want "hotness" that will last, go Playboy.
The 1995 centerfold will always be hot,
even if the model no longer is.
"I disapprove of what you say, but I will defend to the death your right to say it." - historian Evelyn Beatrice Hall
The source is a video repair shop in flyover territory which charges $60/hour for labor. Here in China, I can get my DVD player repaired for $3-10 because the cost of labor is so low. Indeed, one of the delights of living here is you can actually get things repaired. I'm just so used to automatically buying a new electric razor, rice cooker, electric lamp, (etc) when mine breaks. Here, I can actually get it fixed! In America, don't even bother phoning the repair shop as they'll just tell you that the cost of a new unit is less than the cost of their labor.
Don't let that put you off of blaming stupid Americans who are unwilling and unable to repair their own equipment and of course blaming those eeeeevil profit-makers. The only people who see the world the right way are a small group of activists, for example yourself!
Shutting down free speech with violence isn't fighting fascism. It IS fascism!
Reading the article, it appears that the purpose of the resistors is NOT to lock out manufacturers, but to inform the ipod of the amount of current to draw from the charger. They found different manufacturers using different values of resistors. From the looks of it, one resistor sets the amount, and the other resister serves as a "checksum of sorts, complementing the other resistor correctly to verify the value. Getting the value wrong could very easily cause a fire, so this is important to make sure you get it right.
This is not surprising, as USB does not allow variable voltage, and current is supplied completely on demand with no regard to the provider. So you either have your device set to draw a fixed amount of power (current) and limit your options to *1*, or you develop some simpler way to tell the device how much power (current) a device can demand from any given charger.
The only other option would be to use the data pins and actually communicate over the usb spec normally and outright tell the device how much power to draw. (which is actually already in the USB specs) Apple would have probably preferred to go this route, but that would significantly increase the complexity of the power adapters. All the people that are whining about Apple being nasty about this need to get some education. Apple's other two options were to make chargers cost more, or to not be able to offer both fast (wall power) and slow (AA batts) chargers.
The only group that's more thick-headed than the Apple zealots, are the anti-Apple zealots.
I work for the Department of Redundancy Department.
"So might as well go for the brainy, geeky girl because that will last. The beauty won't."
++ for extreme truthiness!
"This post is an artistic work of fiction and falsehood. Only a fool would take anything posted here as fact."
Is there a practical reason that the iPhone / iPod cannot be recharged and / or synced via a simple USB mico connector interface?
Yes... Profit!
For justice, we must go to Don Corleone
Yes, but will she blend?
We all love to call out Apple when they design deliberate incompatibility into their devices, but there is a perfectly valid technical reason for what Apple is doing here, and, in fact, they are following a USB specification (which LadyAda unfortunaterly didn't even test).
Without data communications or when suspended, devices may legally draw no more than 2.5mA from a host, which is useless for charging. In fact, even if you're generous and pretend they're connected, devices are not allowed to draw more than 100mA without negotiating for a higher current, which requires actually talking to the host, and 100mA is still too little to charge properly. 500mA is the maximum allowed by the USB spec, but devices must negotiate it (there may be too many devices on the bus for negotiation to succeed).
Before there was a spec for "dumb" USB chargers, Apple used the resistors as a sentinel to avoid drawing too much current from undersized chargers in order to avoid damaging the host. This is a hack, but it works, and honestly, we're smart enough to figure out a couple resistors on the data lines. It's not like they're using crypto auth on the charger. They have a perfectly valid reason to do this. Devices which charge from "dumb" chargers aren't following the spec, though this is a common industry practice.
As it turns out, the USB-IF came up with a USB Battery Charging spec. The spec is long and boring, but it boils down to: short together the data lines (no resistors required) and you indicate that you're a dumb charger that can supply anywhere from 0.5A to 1.5A.
Guess what happens when you short the data lines of an iPhone 3G and supply 5V. Did Apple just follow a standard? Incredible!
(Yes, I'm not following the USB spec there by in turn using a USB cable to supply the 5V and not negotiating over its data lines. I didn't feel like grabbing a dedicated 5V PSU for the shot, so sue me.)
Airway.
Breathing.
Circulation.
Dick? (checks) Nope. Houston we're ready for liftoff.
Erection? (checks self) Nope. Houston, we have a problem.
When you have nothing left to burn you must set yourself on fire
Dude, has it occurred to you that given she has a science blog with a very nice picture of herself setup obviously next to it kinda saying "Look at me, I'm a pretty little geek girl", she probably likes the attention? I'm not trying to knock her or anything, it's a perfectly normal and reasonable thing to like attention. I also greatly doubt that she wants to have wild monkey-sex with any great percentage of her readers, I'm not saying that either. She clearly likes to be paid attention to: both for her obvious intelligence and for her equally obvious good looks. Her website gives her to opportunity for both in a very safe and impersonal way, good on her. Don't expect people to ignore that she's pretty though.
Personally I kinda liked Ada better. I'm more of a technologist than a scientist, and I like the alt-girl look. To each their own though.
I don't need a million points of light, just two points of multi-mode fiber and a 10 Gig-E router.
You can upgrade to the latest model every few years. As long as you can afford it.
If all else fails, immortality can always be assured by spectacular error.
Funny, my Android phone does the same exact thing and it uses a standard USB micro interface. You need a special plug to get the full 1000ma charging, but it can use regular plugs too and charge at 500ma without frying anything.
We hope your rules and wisdom choke you / Now we are one in everlasting peace
If that was the case and it wasn't for profit, why would they require a secret contract? I get why the resistors were initially added but I'm not understanding why it needs to be a trade secret.
WTF Slashdot, why do I have to login 50 times to post?
But there is nothing to stop them just drawing the 500mA if the right sort of charger is not detected. Refusing to charge at all unless the licensed parts are present is pure market control, nothing else.
except dumb womens usually aren't any good in bed.
Smart women are far better. However crazy women are the best, but get the HELL out when you are done.
The Kruger Dunning explains most post on
You got modded insightful?
My N900 charges via a USB cable. It charges at 1200mA with the fast Nokia charger, at 500mA with the slow Nokia charger or PC USB port and at what appears around 300mA with a $2 Chinese car charger.
And they certainly don't charge third parties to provide them with secret recipes on how to make the chargers work.
Or naw... you are right, Apple never does anything wrong, just uncool people complaining about everything...
Violence is the last refuge of the incompetent. Polar Scope Align for iOS
Since when did jerking off in the bushes outside someone's bedroom window count as rape? Jesus, guys...it's not as if I'm sort of sicko.
I guarantee Sarah is perfectly content enough and at ease with sexuality, being a grown woman of good looks and high intelligence, that comments by random nerds on a geek site don't at all even register on her radar as a source of concern. You don't need to "protect" her from the evil lusty nerds, he-man, she's gonna be OK.
Actually, it has occurred to me, as I am a personal friend of Sarah's. You may not believe me, but either way, that's somewhat besides my point. I'm sure she wants attention for her outreach work and her scientific research, but to get attention only or primarily because of one's looks is to very unwelcoming. It serves to alienate people, to denigrate them-- it's why we have terms like "sexual objectification" in our language.
OK, this just keeps getting better and better. As I read more of your posts about this girl, I begin to see what your motivation is. You're the overprotective geek friend/wannabe lover who thinks by defending her honor on some random geek message board, you will curry favor with her and this will somehow lead to her fucking you. I'm sad to inform you this will never happen.
This cannot be! Apple is about supplying the best customer experience, about rolling out magical devices to the masses to free them from the bondage and slavery of technology as imposed by those proprietary, secretive for-profit companies!
Browsing at +1 - no ACs, I ignore their posts. So refreshing!