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The Lightning Digital AV Adapter Surprise
- zacharyvoase 14y agoMost cables that adapt signals from one format to another are 'active' (that is, contain a microcontroller). c.f.: https://en.wikipedia.org/wiki/Active_cable https://en.wikipedia.org/wiki/Active_cable
- drivebyacct2 14y agoSomeone is very confused as to what "AirPlay" is. This doesn't make any sense. AirPlay is a network protocol tied to mDNS/Bonjour. There's no way the Lightning controller is supporting an entire network stack plus video transcription. Calling this only half-thought-out seems generous. I thought it was well known that these were smart cables. Thunderbolt is the same way. At best the SoC is some sort of smarter adapter.
- tptacek 14y agoYou think Cabel Sasser doesn't know what Airplay is?
- drivebyacct2 14y agoI honestly don't know. Someone is somehow implying that the adapter is implementing a full stack capable of being an AirPlay receiver and transcoding video on the fly. I think Cabel is wrong or has explained what they think is occuring incorrectly. /shrug
- tptacek 14y agoSorry, I don't mean to sound like I'm attacking. Was seriously asking.
- drivebyacct2 14y agoNo, I understand. "Someone is confused about AirPlay" was more accusatory than I meant. I genuinely don't know if Cabel knows much about AirPlay, I only know what I know from working with it and uPnP/DLNA for the last some months, and it made this seem unlikely to me. He may well know more than I and I learn something new and useful. :) Based on the anonymous comment in this thread and this tweet, I'm potentially happy to eat my words. https://twitter.com/jmreid/status/306987650001301505 https://twitter.com/jmreid/status/306987650001301505
- cabel 14y agoIn this case, AirPlay is our easier-to-understand way of saying "the results you're getting are exactly the same as when you stream iOS video using AirPlay". (Which is really weird for a video-out dongle! Especially since the former, non-Lightning one did proper video out.) I've tweaked the post to make it clearer that AirPlay isn't _necessarily_ the _exact_ mechanism being used! It could just be H.264 or MPEG or whatever. Mostly I'd love to know exactly what this chip/system does, so if anyone here with far more advanced hardware knowledge than any of us have feels up to hacking around, that'd be amazing! :) The key takeaways from the post are: 1. It's feels unusual that a AV adapter would have a full SoC ARM-based CPU with RAM etc, not just a video encoder/decoder chip. Is it unusual? Let me know. :) 2. It's a bummer that the Video Out isn't very good, and not true 1080p, and has MPEG artifacts. (Thanks for sharing the link.)
- drivebyacct2 14y agoYeah, someone mentioned something similar elsewhere in the thread and it certainly makes sense to me. It fits in with the comparison to Miracast, the need for hardware support for full screen mirroring over AirPlay. I can see the adapter processing a stream in a similar format or some such as AirPlay (without being a classic "AirPlay receiver" which is what I was hung up on) For your two points: 1. I think that comes with the territory of being a Lightnin accessory and makes sense if they're doing some sort of compression or something before hand. It certainly fits with Apple's persona. Control the content, don't let any-old-body create a video adapter. They have to deal with Apple's handshake/stream/whatever because Apple doesn't pin-out the HDMI for the Lightning connector... 2. That is a major bummer and seems like one of those "details" that Apple would get right. I'm certainly curious the more I think about it as well.
- supercoder 14y agoI think they're way off on the theory the cable is running iOS. I think what's most likely is the phone is putting out a h264 stream and the chip is just decoding it. Rather than a whole ios stack & AirPlay protocol. Sure this shares some similarities with how AirPlay works (showing a h264 stream from the device ) but wouldn't require a whole system on a chip just for showing this feed.
- jey 14y agoWhy not? AirPlay is a pretty high-level protocol, and it's got an ARM SoC, so the natural thing for Apple to do would be to use the ARM version of XNU with a minimal userland that has their AirPlay implementation and whatever codecs it needs. At least, If someone handed me one of these dongles with a copy of the protocol spec and asked me to write the software for it, I'd do something similar except using Linux. (Sidenote: buildroot is great for creating embedded systems running Linux.)
- deleted 14y ago[deleted]
- acgourley 14y agoRight, definitely just the video transport part of AirPlay. This is exactly how Miracast works too, except that's over a direct wifi connection between 2 devices.
- userna 14y agoActually, they're dead on. (And no, I won't corroborate that further. But it does download a stub copy of iOS.)
- pifflesnort 14y agoThis provides no useful information whatsoever. I wouldn't be hugely surprised if they wrote code to the ARM MCU (if it has 2GB of RAM to work with), but what does "stub copy of iOS" even mean? Also. Jimmy Hoffa is buried inside that microcontroller. I won't corroborate this further, but this is the dead-on truth.
- shabble 14y agoIf bored, you could try probing those various little gold test pads on the off chance they have a debug port[1] somewhere. Then again, Apple paranoia makes that overwhelmingly unlikely. [1] http://www.devttys0.com/2012/11/reverse-engineering-serial-ports/ http://www.devttys0.com/2012/11/reverse-engineering-serial-p... (although JTAG is probably much more likely if anything)
- signed0 14y agoSo instead of just going with USB3 like other phone manufacturers and having native HDMI they created their own interface that results in an a picture display with noticeable artifacts.
- evan_ 14y agoWhat's USB3 got to do with HDMI?
- dangrossman 14y agoMost non-Apple smartphones have micro-USB ports for charging, and most made in the past few years also support sending an HDMI signal through this port, either via MHL [1] or SlimPort (notably, Nexus 4). All it takes is a $10 adapter cable rather than a $40 SoC transcoding things. 1: http://en.wikipedia.org/wiki/Mobile_High-Definition_Link#Mobile_devices http://en.wikipedia.org/wiki/Mobile_High-Definition_Link#Mob...
- jws 14y agoThey also have hardware in the phone to generated HDMI (although electrically modified to fit on the USB connector). Given that only a tiny percentage of people will ever plug their phone into HDMI, it makes sense to have that minority pony up $40 instead of making everyone pay an extra dollar for the hardware they will never use.
- signed0 14y agoBut if they cared about cutting costs they wouldn't have invented their own cable to begin with. When has Apple ever worried about making people pay for things they don't use? I'm disappointed because Lightening was billed as the next innovation in design, but if the picture quality is worse then what's the point?
- arrrg 14y agoApple has no problem making pay – but they do have a problem making people pay for stuff they don’t use. Nothing to do with costs per se, it’s more a philosophical stance.
- fnordfnordfnord 14y ago>What could all of those resistors be for? The brown ones a most likely capacitors.
- mbell 14y agoThe small parts are just standard 0201 size. Brown ones are MLCC caps, black are resistors.
- MBCook 14y agoApple says the adapter can play 1080p video. Is it possible that it could play 1080p video, but the on-device encoding is limited to 1600x900, so can't mirror at 1080p?
- gojomo 14y agoMaybe it's a chip to prevent the cable from being used to display any 'barely legal teens'.
- seanp2k2 14y agoOne must wonder why they chose to expend significant R&D to make a complicated, power-sucking adapter for use on a mobile device that provides sub-par output and costs quite a bit more than a "dumb" cable. Maybe I'm missing something, but I feel like Lightning is just the next Firewire without all the usefulness that FW had (low latency, dedicated bus that wasn't USB, lots of pro audio gear that worked with it, ability to daisy-chain, faster real-world speeds than USB, near-ubiquity before FW800 came out, super small form factor (the 4pin is tiny; not much bigger than a lightning)).
- rangibaby 14y agoLightning is a replacement for Apple's old and huge dock connector. You're probably thinking of Thunderbolt.
- stephengillie 14y agoThunderbolt definitely is designed as a replacement for Firewire, USB, 10 Gbit Ethernet, HDMI, and all other current wired connections. It's been advertised as such for a while. I first heard about Lightning just 2 days ago. I'm now confused between Thunderbolt and Lightning, and frustrated that I'll have to go learn about their differences.
- mjs 14y agoAll that setup and no "very very frightening" joke?!
- lostlogin 14y agoNicely done. The very very frightening for me is the clunky move to wireless. There are about 20 Macs in the office, and when half the keyboard batteries go flat after a long weekend and you need to quickly check something, scrounging the building for a USB keyboard is tiring. This combined with airplays momentary drop outs and refusal to start (infrequent but annoying) make me sad. It's like we're so close to the cableless world, but just far enough away that its awful.
- Cushman 14y agoI assume that someone is now trying to install Linux on one of these?
- Someone 14y agoIf this thing decodes the vodeo stream and gets the code the run from the iOS device when connected, might we see a future iOS update that enables full HD, or would the video decoder hardware be the limiting factor here? Also, for jailbreakers: find that code, and improve it. Finally: I find it a pity that Panic reports this now. It would have been funny if it were published exactly one month later (or is the clock in their CMS off by a month?)
- mjs 14y agoThe description on the UK Apple Store says that it "mirrors exactly what you see on your device", so that needs adjustment, at least. http://store.apple.com/uk/product/MD826ZM/A/lightning-digital-av-adapter http://store.apple.com/uk/product/MD826ZM/A/lightning-digita...
- Joeri 14y agoSomeone isn't practiced enough at weaselwords yet. Had they said 'mirrors in its entirety what you see on your device', they would have been accurate while misleading, while now they're just wrong.
- nirvana 14y agoThe 30 pin dock had 30 pins so it could put video out directly and things like that. Lightening is a SERIAL FORMAT with 9pins. So it streams audio and video out in an encoded form. The AV adapter, need to take that audio and video and turn it into a standardized AV format for the AV plugs. Now, rather than a lot of odd incompatibilities because Apple added new features to new devices that older docks don't support, we have a common communication format in lightening that should be much more robust going forward. Apple can add whatever protocols it needs over the serial connection to support future tech, rather than the old way of redefining what some of those 30 pins meant from period to period-- remember the 30 pin connecter started out in a time when there was firewire taking up some of those pins! People like to ascribe nefarious purposes to Apple or claim apple is "rippng them off" because a small computer that does digital AV conversion costs $30... and they dont' realize that the 30 pin connector didnt' do any conversion of formats was just bringing the signals out to a standard connector. This one actually has to do work, which is why it has a SoC on it.
- revelation 14y agoPeople don't realize that the 30 pin connector didn't do any conversion of formats because they don't care. They want a connector, and what Apple delivered is a power-sipping SOC that actively throws information away, given the artifacts seen, and then upscales to 1080p because they didn't even have enough throughput to get lossy compressed 1080p through the bus. So yes you get your 30$ worth of components but it's horribly inferior to a 5$ adapter you can get for every other connector on the planet. It's a rip off alright.
- lostlogin 14y agoA rip off in the sense that its a crappy output, not in that they are overcharging. I see mention that its likely making no money or actually losing money selling this cable.
- bsaul 14y agoI really don't get the logic. As if the cable was the thing that you would absolutely want to keep going from one version of the iphone to the other. If a new technology is out, (let's say 4k output), you'd have to upgrade memory and cpu to handle that power anyway, along with a new TV or monitor, and pretty much everything along the chain. Hypothetically beeing able to save the cable seems really not the problem anyway..
- mekpro 14y agoDon't be panic if the cable get kernel panic.
- lostlogin 14y agoHaving just spent an evening trying to sort a strange video issue which turned out to be an intermittent issue with a component cable, the thought of this isn't nice.
- alive-or-not 14y agoVery interesting investigation. I heard somewhere that the Apple lightning cable, that comes with newer iPod, iPhone, iPads contains a chip and we'll be very hard to replicate (by Chinese cloners). Any insight on this?
- senthilnayagam 14y agoIt is pretty exciting to think about possibilities * Jail break this cable, if this has some OS, use instead of raspberry Pi * is Apple bringing Android ADK style interfaces