Apple's Lightning Digital AV Adapter is a Full-Fledged Computer

Panic, the developers behind apps like Coda and Transmit, spent some time disassembling the Lightning Digital AV cable that allows iOS devices like the iPad mini and the iPhone 5 to output HDMI to televisions.

The company discovered that, like its Lightning to 30-pin brethren, the Digital AV adapter is considerably more complicated than it would appear. Among other discoveries, Panic found an ARM chip and 256MB of RAM inside.

Digitalav

There are a lot of questions. What OS does it boot? @jmreid thinks the adapter copies over a “mini iOS” (!) from the device and boots it in a few seconds every time it’s connected, which would explain the fairly lengthy startup time for video out. Why do this crazy thing at all? All we can figure is that the small number of Lightning pins prevented them from doing raw HDMI period, and the elegance of the adapter trumped the need for traditional video out, so someone had to think seriously out of the box. Or maybe they want get as much functionality out of the iPad as possible to reduce cost and complexity.

Panic conjectures that for some reason the Lightning port isn't capable of outputting raw HDMI -- something that should give an extremely high quality image -- and instead uses a form of AirPlay to output video, delivering a lower quality video signal.

Update: Panic highlights this comment from an anonymous reader hinting at being an Apple engineer, which offers more details about how the adapter works and indicating that code updates are being made to improve the video quality.

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. [...]

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.

Top Rated Comments

lostngone Avatar
145 months ago
Listen sonny!

Back in my day the only thing our cables had in them was Lead and Copper, and that is how we liked it!!!
Score: 57 Votes (Like | Disagree)
Fatalbert Avatar
145 months ago
256MB?!??!?!?!!
That's how much RAM my iMac G5 had.
Score: 51 Votes (Like | Disagree)
Eidorian Avatar
145 months ago
Overkill for inferior performance.
Score: 49 Votes (Like | Disagree)
commander.data Avatar
145 months ago
Kind of sad that the 4th gen iPod Touch that they still sell for $199 and up only has as much RAM as an AV Adapter.
Score: 49 Votes (Like | Disagree)
genovelle Avatar
145 months ago
Yet more proof that lightning is a junky and expensive connector. 2013 and can't output 1080p?

This is the year of the Android.
Isn't this an apple fan site?!!! Why are you here instead enjoying the company of your brethren on an android site?
Score: 48 Votes (Like | Disagree)
macsrcool1234 Avatar
145 months ago
Yet more proof that lightning is a junky and expensive connector. 2013 and can't output 1080p?

This is the year of the Android.
Score: 41 Votes (Like | Disagree)

Popular Stories

reset password request iphone

Warning: Apple Users Targeted in Phishing Attack Involving Rapid Password Reset Requests

Tuesday March 26, 2024 4:34 pm PDT by
Phishing attacks taking advantage of Apple's password reset feature have become increasingly common, according to a report from KrebsOnSecurity. Multiple Apple users have been targeted in an attack that bombards them with an endless stream of notifications or multi-factor authentication (MFA) messages in an attempt to cause panic so they'll respond favorably to social engineering. An...
iPhone Home Screen Gradient Blank Spaces 1

Sources: iOS 18 Lets Apps Be Placed Anywhere on Home Screen Grid

Sunday March 24, 2024 1:33 pm PDT by
iOS 18 will give iPhone users greater control over Home Screen app icon arrangement, according to sources familiar with the matter. While app icons will likely remain locked to an invisible grid system on the Home Screen, to ensure there is some uniformity, our sources say that users will be able to arrange icons more freely on iOS 18. For example, we expect that the update will introduce...
maxresdefault

Apple Announces WWDC 2024 Event for June 10 to 14

Tuesday March 26, 2024 10:02 am PDT by
Apple today announced that its 35th annual Worldwide Developers Conference is set to take place from Monday, June 10 to Friday, June 14. As with WWDC events since 2020, WWDC 2024 will be an online event that is open to all developers at no cost. Subscribe to the MacRumors YouTube channel for more videos. WWDC 2024 will include online sessions and labs so that developers can learn about new...
iPad Pro 2024 Landscape Camera Feature

New iPad Pro Again Rumored to Feature Landscape Front-Facing Camera

Monday March 25, 2024 5:43 am PDT by
The next-generation iPad Pro will feature a landscape-oriented front-facing camera for the first time, according to the Apple leaker known as "Instant Digital." Instant Digital reiterated the design change earlier today on Weibo with a simple accompanying 2D image. The post reveals that the entire TrueDepth camera array will move to the right side of the device, while the microphone will...
apple maps 3d feature

Apple Maps May Gain Custom Routes With iOS 18

Tuesday March 26, 2024 3:10 pm PDT by
Apple may be planning to add support for "custom routes" in Apple Maps in iOS 18, according to code reviewed by MacRumors. Apple Maps does not currently offer a way to input self-selected routes, with Maps users limited to Apple's pre-selected options, but that may change in iOS 18. Apple has pushed an iOS 18 file to its maps backend labeled "CustomRouteCreation." While not much is revealed...
sonoma desktop wwdc

Apple Releases macOS Sonoma 14.4.1 With Fix for USB Hub Bug

Monday March 25, 2024 10:10 am PDT by
Apple today released macOS Sonoma 14.4.1, a minor update for the macOS Sonoma operating system that launched last September. macOS Sonoma 14.4.1 comes three weeks after macOS Sonoma 14.4. The ‌‌‌‌macOS Sonoma‌‌ 14.4‌.1 update can be downloaded for free on all eligible Macs using the Software Update section of System Settings. There's also a macOS 13.6.6 release for those who...
Generic iOS 18 Feature Purple

iOS 18 Will Finally Bring This Android Feature to iPhone

Monday March 25, 2024 6:42 am PDT by
iOS 18 will allow iPhone users to place app icons anywhere on the Home Screen grid, according to sources familiar with development of the software update. This basic feature has long been available on Android smartphones. While app icons will likely remain locked to an invisible grid system on the Home Screen, our sources said that users will be able to arrange icons more freely on iOS 18....
Generic iOS 18 Feature Purple

iOS 18: What to Expect From 'Biggest' Update in iPhone's History

Wednesday March 27, 2024 11:10 am PDT by
At least some Apple software engineers continue to believe that iOS 18 will be the "biggest" update in the iPhone's history, according to Bloomberg's Mark Gurman. Below, we recap rumored features and changes for the iPhone. "The iOS 18 update is expected to be the most ambitious overhaul of the iPhone's software in its history, according to people working on the upgrade," wrote Gurman, in a r...