4 ms·

> 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 thi

> 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 when connect your lightning-USB cable to your iPhone, your iPhone squawks and says "What is this?" and the cable says "I'm USB". The iPhone then sets its pinout to USB mode and off you go. What's so great about this, why not just use USB? I think the secret sauce is that Apple wants to surreptitiously invent new pinouts with faster data rates, without consulting any standards bodies and having to rally industry support on TVs, computers, et al. They just build some new controller to push Lightning at 2Gbps+, put it in new iPhones, and build active cables that spit out HDMI or UHDTV or USB3 or whatever it is the kids are doing these days. The active cables degrade gracefully for hardware running at the slower data rate. What I think you are seeing right now, is the dry run with the off-the-shelf controller. Get manufacturing ramped up. You need this to plug your phone into a computer anyway. But it's just the tick. Wait for the tock. Now the only thing that puzzles me is why they settled on 8 pins, when USB3 is 9. Obviously they wanted an even number so you could plug it in every which way, but you would think stepping up to 10 pins would let them use off-the-shelf USB3 controllers instead of USB2. Maybe they can do USB3 on 8-pins somehow, or maybe the tock will be ready fast enough that it's not worth it. Further reading: http://brockerhoff.net/blog/2012/09/23/boom-pins/ http://brockerhoff.net/blog/2012/09/23/boom-pins/

dmishe 14y ago
Yep, and the comment about them using already existent h264 support in hardware I think supports dry-run-fastest-to-deadline solution. Re pins, I'm not EE either, but I don't get why people concern about number of pins so much, as I asked earlier in this thread, is there a relation between number of pins and bandwidth (well with physics involved there is _some_)?
- taligent 14y ago
  Why wouldn't they use H.264 and their existing hardware ? Do you really think it makes more sense to decode H.264 on the device then re-encode it in another format and then decode that on the adapter ? Sounds slow, illogical and bound to introduce more artifacts.
  - dmishe 14y ago
    Nope. This is _the_ question here, what prevented them from pushing framebuffer data to the adapter, which then puts it into HDMI compatible form
    - jlgreco 14y ago
      Worse case, you have two pins, one on each side like any other, that are both actually the same pin.
    - seabee 14y ago
      You'd need 3Gbps to push uncompressed 1080p data. If you look at USB 3.0 and make a not-unreasonable bet that Lightning is slower, then you simply don't have the bandwidth to do so.
      - StringyBob 14y ago
        As well as bandwidth, power consumption. Chucking 3Gbps down a long wire is going to reduce battery life for a mobile product. Perhaps the controller can support it, but heat dissipation in the phone is significant?
        morsch 14y ago
        I can't imagine that compressing and decompressing MPEG 4 uses less power, given specialised hardware for each task.
        makomk 14y ago
        Actually, that doesn't make sense - the adapter is powered from the iPhone or iPad and still has to chuck 3 Gbps down a long wire, except now you're using the iPhone's h.264 encode hardware and an entire ARM SoC in the adapter which you have to power too.
glitch 14y ago
> Obviously they wanted an even number so you could plug it in every which way How so? A center pin is still the center pin when you flip it around. Odd pin counts work fine.
- drewcrawford 14y ago
  Well, there was a big whoop about the thinness of the connector when they announced it being necessary for very thin devices. Can we manufacture non-brittle connectors with center pins that are 1.5mm thick?
bluthru 14y ago
>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?
- guan 14y ago
  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.

dmishe 14y ago

Yep, and the comment about them using already existent h264 support in hardware I think supports dry-run-fastest-to-deadline solution. Re pins, I'm not EE either, but I don't get why people concern about number of pins so much, as I asked earlier in this thread, is there a relation between number of pins and bandwidth (well with physics involved there is _some_)?

taligent 14y ago
Why wouldn't they use H.264 and their existing hardware ? Do you really think it makes more sense to decode H.264 on the device then re-encode it in another format and then decode that on the adapter ? Sounds slow, illogical and bound to introduce more artifacts.
- dmishe 14y ago
  Nope. This is _the_ question here, what prevented them from pushing framebuffer data to the adapter, which then puts it into HDMI compatible form
  - jlgreco 14y ago
    Worse case, you have two pins, one on each side like any other, that are both actually the same pin.
  - seabee 14y ago
    You'd need 3Gbps to push uncompressed 1080p data. If you look at USB 3.0 and make a not-unreasonable bet that Lightning is slower, then you simply don't have the bandwidth to do so.
    - StringyBob 14y ago
      As well as bandwidth, power consumption. Chucking 3Gbps down a long wire is going to reduce battery life for a mobile product. Perhaps the controller can support it, but heat dissipation in the phone is significant?
      - morsch 14y ago
        I can't imagine that compressing and decompressing MPEG 4 uses less power, given specialised hardware for each task.
      - makomk 14y ago
        Actually, that doesn't make sense - the adapter is powered from the iPhone or iPad and still has to chuck 3 Gbps down a long wire, except now you're using the iPhone's h.264 encode hardware and an entire ARM SoC in the adapter which you have to power too.

glitch 14y ago

> Obviously they wanted an even number so you could plug it in every which way How so? A center pin is still the center pin when you flip it around. Odd pin counts work fine.

drewcrawford 14y ago
Well, there was a big whoop about the thinness of the connector when they announced it being necessary for very thin devices. Can we manufacture non-brittle connectors with center pins that are 1.5mm thick?

bluthru 14y ago

>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?

guan 14y ago
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.