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display – How to connect to, and power an external monitor from, an iPad using USB-C hub?

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It appears the Asus MB16ACV uses DisplayLink for video. Maybe it supports some other protocol too, like the much more common DisplayPort protocol, but I could not find an answer on that with a quick look. This can be a problem since it appears that there’s no DisplayLink drivers for iPad.

(I know DisplayLink and DisplayPort are just too similar looking and can confuse people. At least I’m confused sometimes.)

DisplayLink is a means to communicate video by USB. Built into iPadOS are drivers for a quite a few USB devices, and DisplayLink is not among them. There’s DisplayLink drivers available for download for MacOS, Windows, Android, ChromeOS, and Ubuntu, but not iPadOS.

Without drivers iPadOS would see DisplayLink displays as an attached USB device with a vendor ID and product ID that matches nothing in its driver database. Without iPadOS drivers there’s the option to put some kind of device in the middle with sufficient complexity to do the required translation. This would be almost certainly more costly than a new iPad and portable display. Perhaps I overestimate the costs but it should not be a leap to at least put it at more than it is worth, or more than other existing options.

It’s possible to see drivers in the future, but not today.

I discovered the DisplayLink driver issue while investigating the MB16ACV power consumption. It consumes up to 15 watts, and that’s a lot for a USB device. Finding a USB-C hub that will provide 15 watts to downstream USB-C ports is not difficult, but it’s not universal as there are plenty that provide 7.5 watts. Power to an upstream port is often not so limited but upstream and downstream have meanings.

The USB-C spec requires most USB-C ports to provide up to 7.5 watts, and allows for up to 15 watts before getting into USB-PD or some other optional protocol. USB-C devices that consume more than 15 watts are pretty well limited to laptops, smart phones, and a few other portable devices. Anything stationary and with USB-C will plug-in to a utility mains outlet.

The physical connection could be done with a Lightning “camera” adapter (which even Apple admits supports many USB devices besides cameras), a hub with 15 watt USB-C ports, and a few inexpensive USB cables. Just to prove such hubs exist I’ll give one example.

I’ll go back to my original point, I may be mistaken about DisplayLink as being the only means to get video on the Asus MB16ACV. If I’m mistaken on the DisplayLink driver issue then I’d appreciate an update. If there’s a Lightning to DisplayPort adapter (and I’m surprised every time I fail to find one) then a DisplayPort to USB-C cable into a USB-C hub should allow for more power to the downstream 15 watt USB-C/DisplayPort ports. If MST support grows then the hub can likely support more than one display.

That was long. What did I miss?

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