Archive for September 14, 2012

Friday, September 14, 2012

Lightning

Rainer Brockerhoff:

People keep asking why Apple didn’t opt for the micro-USB connector. The answer is simple: that connector isn’t smart enough. It has only 5 pins: +5V, Ground, 2 digital data pins, and a sense pin, so most of the dock connector functions wouldn’t work – only charging and syncing would. Also, the pins are so small that no current plug/connector manufacturer allows the 2A needed for iPad charging.

Dan Frakes:

As with the 30-pin connector, the Lightning connector supports video output; Apple told Macworld that Lightning-to-HDMI and Lightning-to-VGA cables will be available “in the coming months.”

Everyone keeps referring to Lightning as a “dock connector,” but I haven’t seen any reporting on actual docks for the iPhone 5.

Update (2012-09-18): Rainer Brockerhoff:

In contrast, support for Lightning will probably need no extra chips and less than a dozen extra pins on the SoC; 8 of these will go straight to the connector. One or two of the pins will probably sense which kind of adapter or charger/cable is connected and the others will go, in parallel, to the power controller – switching them will allow enough current for charging without overloading any particular pin. Any current-hungry drivers, signal converters and so forth wouldn’t on the motherboard at all but inside the plug itself, further reducing cost and power consumption for the bare device.

Update (2012-09-20): Dan Frakes:

Apple has confirmed to Macworld that these adapters support analog and USB audio-out, as well as syncing and charging. However, the adapters don’t support video-out or iPod mode, the latter a special mode that lets particular accessories, such as car stereos and some whole-home-audio systems, display your iPod’s menus on the accessory’s own screen. More cryptically, the online Apple Store’s product pages note that “some 30-pin accessories are not supported.”

Jacqui Cheng:

Apple Senior VP of Marketing Phil Schiller has reportedly said that the company has no plans to release a standalone dock for the upcoming iPhone 5, making it the first of its kind without such an accessory from Apple.

I’ve been using docks since the original U.S. Robotics Pilot. I’ve yet to see a better way to charge a device on my desk, while making it easy to access. Cables are more difficult to connect and disconnect, and they don’t hold the device in the proper orientation.

Update (2012-09-21): Rainer Brockerhoff:

The previous connector had no serious protection against flexing, so previous docks had to grip the back and bottom of the device, which also led to a profusion of plastic dock adapters; Lightning docks should be able to get away with just a simple generic back support.

Update (2012-09-23): Rainer Brockerhoff:

Still, my point here is that everybody is used to cables and adapters that are simple, inexpensive, and consist just of wires leading from one end to the other – after all, this is true for USB, Ethernet, FireWire, and so forth. Even things like DVI-VGA adapters seem to follow this pattern. But things have been getting more complicated lately. Even HDMI cables, which have no active components anywhere, transmit data at such speeds that careful shielding is necessary, and cable prices have stayed relatively high; if you get a cheap cable, you may find out that it doesn’t work well (or at all).

Update (2012-10-04): Phil Dzikiy:

Apple has made significant changes to its Made For iPad/iPhone/iPod (MFi) policies, tightening control over the manufacturing of Lightning accessories. According to the sources, only Apple-approved manufacturing facilities will be allowed to produce Lightning connector accessories, even including third-party accessories. Moreover, Apple hasn’t approved any factories yet, which the sources say will limit the number of Lightning accessories available in the near future.

Update (2012-11-01): Phil Schiller:

We do not plan on making a dock for the iPhone 5. Most people who use docks use them with speaker or clock systems.

Hacking Up an armv7s Library

Matt Galloway (via David Spector):

Well the iPhone 5 has been announced and it just so happens that the architecture it uses is what they’re calling armv7s. This brings in yet another architecture to the mix alongside armv6 and armv7. And I bet you are wondering why you’re getting linker errors when building for armv7s when using external libraries. It’s because those external libraries do not have armv7s versions!

I hadn’t seen Galloway’s blog before; he also has a good post about how objc_retainAutoreleasedReturnValue works.

iPhone 5: Simultaneous Voice and Data

Brian X. Chen (via Eric Blair):

That means when AT&T customers place a phone call and use data on the iPhone 5, both functions will roll back to AT&T’s older network, which can handle them simultaneously. When you place a phone call while using data in an app with a Verizon or Sprint iPhone 5, it will roll back to their older CDMA networks, which are not capable of simultaneously doing calls and data. And that’s why the iPhone 5 on Verizon and Sprint, despite being a 4G LTE device, will still not do both at the same time.

J2ObjC

Google (via Michael Jurewitz):

J2ObjC is an open-source command-line tool from Google that translates Java code to Objective-C for the iOS (iPhone/iPad) platform. This tool enables Java code to be part of an iOS application’s build, as no editing of the generated files is necessary. The goal is to write an app’s non-UI code (such as data access, or application logic) in Java, which is then shared by web apps (using GWT), Android apps, and iOS apps.

There’s some documentation about how it works, e.g. they implemented auto boxing and unboxing and translate overloaded Java methods.