Sidecar in macOS Catalina is limited to newer Macs, but there's a work-around
Sidecar, a feature in macOS 10.15 Catalina that can turn an iPad into a second monitor for a Mac, may be limited to only a small selection of newer Macs at first, with the first beta of the operating system preventing it from being used on a large number of older Macs.
Introduced on Monday as part of macOS Catalina, Sidecar is a feature of both macOS and iPadOS that extends the macOS desktop to the iPad's display. Able to be used both via a cable and wirelessly, the feature can make the iPad a mirrored display or a second screen, including effectively turning it into a graphics tablet when used with the Apple Pencil.
On Wednesday, developer Steve Trougton-Smith posted to Twitter the results of an exploration of the first macOS Catalina developer beta, including a list of devices that Sidecar will be supported on, as well as a blacklist for other hardware.
According to Troughton-Smith, Sidecar supports the 27-inch iMac from Late 2015, the 2016 MacBook Pro, 2018 Mac mini, the new Mac Pro, the 2018 MacBook Air, the Early 216 MacBook and newer models of each device.
While there is a blacklist preventing Sidecar's usage on older models, Troughton-Smith notes there is a terminal command that is supposed to enable it on earlier Macs running the beta, but it is apparently not guaranteed to work. The command reads:
AppleInsider will be reporting live throughout WWDC 2019, starting with the keynote on Monday, June 3. Get every announcement as it happens by downloading the AppleInsider app for iOS, and by making sure to follow us on YouTube, Twitter @appleinsider, Facebook and Instagram.
Introduced on Monday as part of macOS Catalina, Sidecar is a feature of both macOS and iPadOS that extends the macOS desktop to the iPad's display. Able to be used both via a cable and wirelessly, the feature can make the iPad a mirrored display or a second screen, including effectively turning it into a graphics tablet when used with the Apple Pencil.
On Wednesday, developer Steve Trougton-Smith posted to Twitter the results of an exploration of the first macOS Catalina developer beta, including a list of devices that Sidecar will be supported on, as well as a blacklist for other hardware.
According to Troughton-Smith, Sidecar supports the 27-inch iMac from Late 2015, the 2016 MacBook Pro, 2018 Mac mini, the new Mac Pro, the 2018 MacBook Air, the Early 216 MacBook and newer models of each device.
While there is a blacklist preventing Sidecar's usage on older models, Troughton-Smith notes there is a terminal command that is supposed to enable it on earlier Macs running the beta, but it is apparently not guaranteed to work. The command reads:
It is unclear exactly why Apple is limiting the availability of Sidecar to newer devices, but as it is just the first beta, it is possible that Apple could open up support to earlier models ahead of macOS Catalina's release this fall.defaults write com.apple.sidecar.display allowAllDevices -bool YES
AppleInsider will be reporting live throughout WWDC 2019, starting with the keynote on Monday, June 3. Get every announcement as it happens by downloading the AppleInsider app for iOS, and by making sure to follow us on YouTube, Twitter @appleinsider, Facebook and Instagram.
Comments
There won’t be a real technical reason, just Apple trying to push people to newer machines.
Skylake adds hardware encode/decode support for HEVC, so this might just be a case of the Sidecar feature being implemented with HEVC rather than H.264 to reduce bandwidth requirements or allow a higher frame rate. Older Mac models would have to do HEVC encode in software, so enabling the workaround might impose a significant CPU performance load when the display is rapidly changing.
If I'm right, this could impose a similar requirement on the receiving iPad: basic HEVC hardware decode is a feature of the A9 and later processors, so A8 models that can run iOS 13 (iPad Air 2 and iPad mini 4) may be unable to act as a sidecar receiver as they would have to decode the video stream in software.
There was a similar cutoff with the introduction of AirPlay video support: it required a Sandy Bridge or later processor to get H.264 hardware encode support. Third party software (AirParrot) implemented that feature on older Macs by doing the H.264 encode in software, but it caused a fair amount of CPU overhead.
https://everymac.com/systems/apple/imac/specs/imac-core-i5-2.8-21-inch-aluminum-late-2015-specs.html
https://ark.intel.com/content/www/us/en/ark/products/87714/intel-core-i5-5575r-processor-4m-cache-up-to-3-30-ghz.html
https://everymac.com/systems/apple/imac/specs/imac-core-i5-3.2-27-inch-aluminum-retina-5k-late-2015-specs.html
https://ark.intel.com/content/www/us/en/ark/products/88184/intel-core-i5-6500-processor-6m-cache-up-to-3-60-ghz.html
Think about the foolishness of Apple actively supporting old HW going back 4 years with their iPhone but then not including some features that they can't get to work well in all cases for the oldest hardware. If they really wanted to force users into new HW they would limit their OS updates to 3 or 2 or even 1 year old devices, which would be on par with Android.
Do you think Apple is really that stupid to not realize that offering OS updates to old devices will help keep users on old devices?
Skylake does not have hardware decode support for 10-bit HEVC. That was added in Kaby Lake (7th generation), which includes 2017 iMacs.
As of WWDC 2017 (therefore High Sierra), no Macs were going to use hardware support for 10-bit HEVC encode, but it appears Kaby Lake also added that feature.
Given the Skylake processor requirement, that probably means Sidecar is using 8-bit HEVC. In theory it could step up to 10-bit HEVC if the Mac and iPad are new enough.
We also see this go the other way (or un-Sherlocked), as is the case with Back to My Mac pushing many to 3rd-party solutions.
The first version of Quick Sync was introduced in Sandy Bridge (2nd gen Core i3/i5/i7), initially supporting H.264, so some variant of Quick Sync exists in almost all 2011-2012 Macs (apart from the 2012 Mac Pro) and all 2013 and later Macs.
Later processor generations improved Quick Sync and added more video formats. 5th gen (Broadwell) added some VP8 support. 6th gen (Skylake) added 8-bit HEVC encode/decode. The 2015 21.5-inch iMac (5th gen) is excluded from the list of supported models, but the 2015 27-inch iMac (6th gen) is included so Quick Sync in Broadwell does not suffice, implying 8-bit HEVC encode/decode is the required feature.
You can always count on a list of Apple gear that will make the cut for new tech and/or features to bring out the cynics/haters to play the Greedy Apple card. They're also the same trolls to lambast anybody who demonstrates factual examples to the contrary and call them fanboys or ::shudder:: fanbois! LOL
And the instant some new feature doesn't work 100% for 100% of the time for 100% of their customers, it become a FAIL! and a -gate. So it makes sense, to anybody with a room temperature or better IQ that Apple would limit a feature to hard where that will support it, and support it well.
At some point, you have to know when to say 'no'. Just because a feature might work on a older Mac, albeit at 70%, doesn't mean it should.
But sure, it's a horrible, greedy business model to keep making better hardware, and developing newer software to take advantage of it. That sounds downright evil.
Definitely! Currently using TeamViewer to remote into my headless Mini but would like to try it in SideCar and ditch the third-party...