Apple 'insider' explains why vid adapter hides ARM computer
Cable might actually be worth $49 price tag
Mac applications developer Panic has found something interesting inside an Apple video adapter: a computer.
While trying to figure out why video output from some iDevices was so poor, the company cracked open a Lightning AV Adapter, a $US49 accessory that is sold as allowing Apple devices to send video to HDMI devices in glorious 1080p HD, and found a CPU and RAM inside.
Why does a video adapter need a CPU?
An answer, very unusually, seems to have been provided by an Apple employee who joined the burgeoning thread following Panic's blog post about its find.
The comment offers the following explanation:
“The reason why this adapter exists is because Lightning is simply not capable of streaming a 'raw' HDMI signal across the cable. Lightning is a serial bus. There is no clever wire multiplexing involved. Contrary to the opinions presented in this thread, we didn’t do this to screw the customer. We did this to specifically shift the complexity of the “adapter” bit into the adapter itself, leaving the host hardware free of any concerns in regards to what was hanging off the other end of the Lightning cable. If you wanted to produce a Lightning adapter that offered something like a GPIB port (don’t laugh, I know some guys doing exactly this) on the other end, then the only support you need to implement on the iDevice is in software- not hardware. The GPIB adapter contains all the relevant Lightning -> GPIB circuitry.”
The comment later offers the following:
“Certain people are aware that the quality could be better and others are working on it. For the time being, the quality was deemed to be suitably acceptable. Given the dynamic nature of the system (and the fact that the firmware is stored in RAM rather then ROM), updates **will** be made available as a part of future iOS updates. When this will happen I can’t say for anonymous reasons, but these concerns haven’t gone unnoticed.”
That reads an awful lot like an Apple employee breaking cover and ignoring the company's infamous veil of secrecy to actually – shock horror! - comment on something other than how great Apple's products are.
If that's the case, one imagines some of the nastiest HR forms used at Cupertino may just be about to get an airing.
Here in Vulture South, however, we prefer to take a sunnier approach to this story, as an adapter with a CPU and RAM inside might just be the first ever product of its sort to justify its price tag. ®
COMMENTS
Re: Are you kidding?
> You're getting Thunderbolt mixed up with Lightning.
That's very very frightening.
Re: Are you kidding?
But you don't understand. By taking the HDMI connector out the iDevice and putting it in its own adaptor, Apple simplify the iDevice's hardware design and therefore reduce costs and so pass the savings onto... oh.
the screwing began much before this
"Contrary to the opinions presented in this thread, we didn’t do this to screw the customer. "
No, probably not with the adapter. You screwed the consumer when you made the lightning connector (or whatever hipster name you came up for it). It's a crappy connector (to hard to remove because it's way too tight and the part you hold is too small). It's not compatible with accessories (I know, there's an adapter for that, too, but how do all these adapters jive with the magical design philosophy?).
But the real screwing is that there's a perfectly awesome, widely used connector out there: the micro usb. I have dozens of those cables and chargers around, because all my devices use it. Some firm who never innovates, just copies (sam sung what?), even shoots HDMI over it.
Paris, because she loves what you did to her.
Re: Are you kidding?
My bad - I should have said:
An overpriced iDevice that needs an overpriced adaptor with it's own CPU and Ram to push out the same video that loads of Android devices at less than half the price can push out over a $5 (on Amazon) mini-HDMI to HDMI cable.
Re: GPIB?!?! AHHHHHHHH!!!!
It's still in quite widespread use if you look in the right places. While mass-produced stuff has generally abandoned it even in its traditional test equipment heartland it retains the advantage of being very easy to implement - it's the only bus that can transmit at those kinds of speeds while being built on a generic stripboard for example. If the device in question is a unique one-off that's a very strong attraction, since the costs of PCB design and fabrication can't be amortised over a large number of units. The relatively simple protocol (especially by multidrop standards) at both ends of the connection helps massively with those short-run costs too.
I work in just that kind of short-run embedded engineering shop. Several times I have sat down at 9am with a list of requirements and gone home at 5pm having designed a circuit, written the firmware and host software, built the thing and tested it. That's doable with GPIB. The next preferred option would be 10base-T, but that means careful impedance matching, PCB layout, a TCP/IP stack on the device, more sophisticated host software, etc etc. The unit costs will end up lower but you have to offset those against the design costs: that's generally at least a day's work and if the production run is three or four easier is almost always cheaper.
