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(Presumably) Apple engineer comment on Lightning AV adapter design

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Re: (Presumably) Apple engineer comment on Lightning AV adapter design

#141

Post by zyb09 »

rossjudson wrote: post #108
nirvana wrote: post #67

Ideology has trumped engineering, and as hackers, you shouldn't tolerate it. Frankly, all of this has been obvious all along to any competent engineer, since the moment Apple introduced lightening. They described it as a serial bus and talked about how it gave more flexibility. If you think about it for 2 seconds its obviously better to run protocols over a serial bus than to run 30 lines of individual signals, with…

What you're saying is true from an engineering standpoint (serial vs parallel), but has to be placed in the customer's context. In this specific case the quality is bad, operation is unreliable, and the price is high. Consumer devices accept HDMI as input. Serial to parallel video (Lightning to HDMI) is tough without some heavy-duty hardware -- hence the exorbitant cost of these adapters. The SoC design introduces a…

After thinking a little bit about it, I think this approach does make some sense and allows for more flexibility in the future. Keep in mind Lightning was likely designed to last well over a decade and will be used in many different devices.

Now since the adapter is a SoC and it's OS is booted from the device, what that means is, every device has essentially full control over how it wants to output HDMI, without having to change the adapter or the port. Right now this is accomplished using this quirky h.264 encode/decode workaround, but this is first-gen, and it doesn't have to stay that way. Future iDevices might load a different OS onto the SoC and output lossless 1080p using the exact same adapter! And without breaking older devices.

It frees Apple from having to define a fixed method of transmitting HDMI over Lightning now, that is then set in stone for the next 10 years, and has to be supported by every future device.

It also frees them from having unnecessary pins, which might become useless in the future, but have to carry over to every new device (a.k.a. 30-pin connector). And knowing Apple, probably THE top priority of Lightning was to have a slick, easy-to-plug-in-n-out, user-friendly connector, which Lightning admittedly does way better then any MicroUSB standard.

Because in essence, the only thing that is fixed about Lightning is the physical shape and pins, so they focused on getting that aspect right and future-proof. How the data is transmitted can be changed on a device level basis.

Re: (Presumably) Apple engineer comment on Lightning AV adapter design

#142

Post by nathanstitt »

nawitus wrote: post #122
nathanstitt wrote: post #112

Earlier quoted context omitted.

I agree 100%. Software is eating the world, so I'm not sure why everyone is so against this. Maybe it's a case of I didn't complain when they came for my DEC Alpha server with green screen, nor when they took away my Token Ring network, but I will not stand for only using one flimsy cable for all my devices. Come on, this is the tech industry, what did you think was going to happen? What I see Apple's done here is fu…

>Software is eating the world, so I'm not sure why everyone is so against this. Added latency and worse quality are pretty big things. I wan't to send pixels 1:1 to my display device, which this new technology doesn't allow.

I do see where you're coming from, and agree it sucks that they've went backward in quality in this case. To my mind those are implementation details that Apple screwed up. It doesn't invalidate the basic idea though, which is to move the brains of the device into software so that the same connector can be used for a multitude of different functions, some of which don't even exist today.

Admittedly, I'm not privy to whatever design decisions the team that implemented the connector made, but I see no reason why it couldn't have the same fidelity that a straight hdmi cable would have. If I guessed, I'd say that they said 'good enough, ship it' instead of continuing to refine it since they knew they could always send down an update later.

Re: (Presumably) Apple engineer comment on Lightning AV adapter design

#143

Post by mikeash »

rossjudson wrote: post #108
nirvana wrote: post #67

Ideology has trumped engineering, and as hackers, you shouldn't tolerate it. Frankly, all of this has been obvious all along to any competent engineer, since the moment Apple introduced lightening. They described it as a serial bus and talked about how it gave more flexibility. If you think about it for 2 seconds its obviously better to run protocols over a serial bus than to run 30 lines of individual signals, with…

What you're saying is true from an engineering standpoint (serial vs parallel), but has to be placed in the customer's context. In this specific case the quality is bad, operation is unreliable, and the price is high. Consumer devices accept HDMI as input. Serial to parallel video (Lightning to HDMI) is tough without some heavy-duty hardware -- hence the exorbitant cost of these adapters. The SoC design introduces a…

"And it introduces that complexity at a point of physical vulnerability -- people don't treat adapter like tiny fragile computers. They treat them like, well, adapters."

I don't understand this. What makes these things any more fragile than a regular adapter? They are, as far as I understand it, compact, fully solid-state, and about as strong as any consumer electronics of that size would be.

Re: (Presumably) Apple engineer comment on Lightning AV adapter design

#144

Post by mikeash »

jws wrote: post #124
TorbjornLunde wrote: post #113

Earlier quoted context omitted.

I strongly disagree that reversibility is a small feature. Whenever Plugging the chargers to new iOS devices is effortless the same way as headphones jacks. Non-symmetrical connectors are an affront to usability.

I appreciate reversibility once per day. In 2074 days of owning an iPhone and 1065 days of owning an iPad I have never used or wanted an HDMI output. I'd say they made the right tradeoff.

I agree. I don't even have a device with the connector (yet?), but it seems like a major advantage.

Who are all these people popping out of the woodwork wanting a wired connection from their phone to their TV? I'm sure some people do this sometimes, but so many? Why would you even do that? Perhaps this is uncharitable, but it makes me think that most of the people complaining here have never done it, never will, probably never even thought about doing it before, but are now outraged at the thought that the connector is not 100% perfect for this one uncommon use-case.

Re: (Presumably) Apple engineer comment on Lightning AV adapter design

#145

Post by mikeash »

bitcartel wrote: post #21
dmishe wrote: post #2

I think the main takeaway is that yes, lightning is future proof and can adapt to any output you want it to. I do wonder what's the reason for encode/decode cycle was in the first place though.

I think the main takeaway is, why pay for a $50 widget when a $5 cable will do the job? For the consumer who just wants to connect their device to a HDTV, it's crazy they have to pay 10x more just because they're in the Apple ecosystem and not Android. As for being future-proof, by the time some cool new A/V interface hits the market, and we've all updated our TVs, the Lightning devices of today will be in a museum.

Personally, I'll be (vaguely) glad that the price of my next iDevice won't include the cost of HDMI output hardware that I will never use.

Re: (Presumably) Apple engineer comment on Lightning AV adapter design

#146

Post by DenisM »

I think we can all agree that pushing hdmi circuitry off the iPhone reduces cost of the device, increases cost of the dongle, and drops signal quality. We can also speculate that signal quality will increase over time by a combination of better encoding, pass through for already encoded signal, and raw speed upgrade for lightning protocol itself.

What is puzzling is the timing of the release. There is an obvious drop in quality, and no obvious reason to save cost in iPhone 5. They could have let the technology mature to quality parity and only then release it, so what gives? My theory is that Apple came under serious price pressure, as cheap smartphones are now the fastest growing segment of the market, and so they are preparing to ship a very cheap version of the iPhone. Given their position as high-margin company on one hand and pressure from low-margin competition on another, they felt the need to pinch every penny. And so the iPhone 5 ended up being the test bed for the new wave technology with much lower cost of entry, but more expensive accessories. Unfortunately, what we get in the interim are both expensive devices and expensive peripherals.

Re: (Presumably) Apple engineer comment on Lightning AV adapter design

#147

Post by guan »

bluthru wrote: post #50
drewcrawford wrote: post #26

Earlier quoted context omitted.

> If they can't even do 1080p lossless right now, they are in much deeper trouble for the future. Let me try and shed some light on this mystery. Consider this rumor. Also, I am not an electrical engineer, so I may be talking out of my ass. As best as I can tell, Lightning is not (yet, anyway) a real protocol like Firewire, USB, etc. What it is so far is USB with a different connector and some negotiating chips. So w…

>Now the only thing that puzzles me is why they settled on 8 pins, when USB3 is 9. Is the metal prong itself the 9th pin?

If you count them there are actually 16 pins. Apple wants you to think there are only 8 pins and that the connector can be reversed. But nothing prevents them from adding some additional handshaking in a future device that lets them use all 16 pins separately. The connector could still be reversible with additional switching circuitry that routes signals to the correct place depending on how you have rotated the connector.

Re: (Presumably) Apple engineer comment on Lightning AV adapter design

#148

Post by makomk »

rossjudson wrote: post #108
nirvana wrote: post #67

Ideology has trumped engineering, and as hackers, you shouldn't tolerate it. Frankly, all of this has been obvious all along to any competent engineer, since the moment Apple introduced lightening. They described it as a serial bus and talked about how it gave more flexibility. If you think about it for 2 seconds its obviously better to run protocols over a serial bus than to run 30 lines of individual signals, with…

What you're saying is true from an engineering standpoint (serial vs parallel), but has to be placed in the customer's context. In this specific case the quality is bad, operation is unreliable, and the price is high. Consumer devices accept HDMI as input. Serial to parallel video (Lightning to HDMI) is tough without some heavy-duty hardware -- hence the exorbitant cost of these adapters. The SoC design introduces a…

The problem isn't even serial-to-parallel - HDMI is serial based - the problem is that Apple apparently designed Lightning with insufficient bandwidth for uncompressed video, then kludged around it. Then Apple fanboys went on and on about how much more elegant it is than MHL, which has much cheaper HDMI adapters and better video quality because all the MHL adapters have to do is convert one uncompressed serial video data format to another.

I mean, technically speaking Samsung or any of the other manufacturers could've done the same trick as Apple using plain old micro-USB OTG 2.0 with no special hardware support in their phones, no special connectors... but the reviewer community would call them out on it because it's ugly and user hostile, if their engineers even let them get that far.

Re: (Presumably) Apple engineer comment on Lightning AV adapter design

#149

Post by itafroma »

Spykk wrote: post #140
rlanday wrote: post #135

Earlier quoted context omitted.

You do realize that it was Apple that first shipped computers with USB to replace legacy ports, right?

USB was around long before Apple stopped providing PS/2. If you buy a phone or tablet from anyone that isn't Apple you will very likely get a USB port. If you buy Apple you will not. Trying to argue that Apple is somehow looking to the future by providing a serial bus years after it was the norm is hard to comprehend.

Apple never provided PS/2; their solution was the (proprietary?) Apple Desktop Bus: http://en.wikipedia.org/wiki/Apple_Desktop_Bus

You may be thinking of the licensed Mac clones of the mid-90s: some of them did include PS/2 ports.

Re: (Presumably) Apple engineer comment on Lightning AV adapter design

#150

Post by makomk »

giovannibajo1 wrote: post #89
makomk wrote: post #57

Earlier quoted context omitted.

I'm guessing its actual capabilities are basically just USB 2.0. Someone tore apart a Lightning-to-USB sync cable ages ago and the data pins are apparently wired straight through - so we know that Lightning can speak it natively - and given all the focus on simplicity and not doing multiplexing at the expense of more complexity in the adapter I can't see any reason why Apple would develop their own protocol.

That means that the CPU reconfigures the pins into USB2 mode, which means that Lightning can at least do 400Mbps. This is because any SoC nowadays can do low-level USB-device pinout, so it's reasonable to simply pass it through the lightning connector, unlike HDMI or DVI which require specific video encoders. It says nothing about Lightning maximum speed. Besides, whatever maximum speed can be measured with today hw,…

Given there's nothing that can currently use more Lightning bandwidth than USB 2.0, and apparently 3rd-party manufacturers don't have access to anything except USB 2.0 and slow TTL serial, it'd be surprising if it did support anything else. Also quite expensive - Apple's hardware USB implementation is almost certainly third-party IP they've bought in and dropped into place unamended, modifying it to multiplex another protocol they don't need is a waste of money.

Besides, if we're talking about hypothetical future hardware, there's nothing to stop someone doing the same with micro-USB. (In fact, manufacturers already have in the form of MHL.)

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