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by usernew 1166 days ago
So, maybe I'm missing something here, but who is talking about computers? Most things that need to be connected to with HDMI, are TVs. I have 5, none of them take display port or USB-C. The all take HDMI. I have no "monitors" because... Why would I need one (I only "game" things that have to run on dosbox)?

But let's talk computers. And phones. All mine, only have USB-C. I have an old one that has micro, and I chromecast the screen from that one. I connect them all to TVs. With HDMI on the TV end.

So literally your dead on arrival example is not even present in the life of my household, while what's talked about in the article is widely used.

2 comments

It's not used at all. HDMI alt-mode is several years old and nothing implements it. Even HDMI LA considers it dead now, they closed their certification program for it.

In practice, video over USB-C uses either DP alt-mode, Thunderbolt or USB4 (and the latter ones encapsulate DP over their own protocols). All USB-C to HDMI cables and adapters actually use DisplayPort and converters. HDMI alt-mode was indeed dead on arrival.

I'm not addressing the Alt-mode. Please read what was written, and reply to what was written. The comment to which I replied said you connect devices with display port, not HDMI, because all your devices are monitors. The real-world use case is USB-C to HDMI, to connect to a TV. I have no idea what my cables do, but they have USB-C on one end, and HDMI, not DP on the other, and I plug them into the TV.

The comment stated you don't need HDMI on the other end. I am not arguing for "Alt-mode" protocol, nor did I write "Alt-mode" anywhere in my comment. I am specifically replying to the wrong fact that most people use USB-C to connect to and HDMI port, not a DP port, on the other end of the cable.

From a quick google, the reason Alt mode is "dead" is because most devices natively support HDMI and you don't need alt-mode. https://www.notebookcheck.net/The-demise-of-HDMI-over-USB-C-...

You seem pretty confused.

> From a quick google, the reason Alt mode is "dead" is because most devices natively support HDMI and you don't need alt-mode.

If you do video over USB-C, you need alt-mode. Everything uses DisplayPort alt-mode and converts it to HDMI if needed. These days most devices have no other form of video connectivity than USB-C.

You link to an article that literally states "DisplayPort has won".

> The real-world use case is USB-C to HDMI, to connect to a TV.

The real world use case is to connect a PC or phone to an external display. Usually that's going to be a PC monitor, where physical DisplayPort actually is ubiquitous these days. Personally, I don't even have a TV - I'm not exactly a gamer so I don't see why would I need one.

(I actually connect my laptop to a screen using HDMI connector on the screen side, but that's only because it's about 10 years old :P)

I recently picked up a $100 external display on amazon. It's essentially a laptop screen with a magnetic cover a la surface tablet.

It's just a screen, no touch capabilities or any real processing onboard.

This screen has 3 usbc ports and a mini hdmi port. It also has an audio out jack.

In theory, it can be driven with a usbc to usbc cable from a phone or computer, but I don't have a device that can drive it this way.

The second usbc port is auxiliary power for when your phone can't power the whole screen.

The third usbc port is for daisy chaining another device.

The way I use this thing is from my (fairly old) laptop that only has display port out. I have an adapter that changes the DP port on my laptop to full side hdmi and then use the hdmi to hdmi mini cable that came with the screen.

Unfortunately, this setup does not pass sound to the audio jack. I wish my laptop had an hdmi port instead.

I have a similar portable screen with almost the same set connectors (only two USB-C ports and miniHDMI, no daisy chaining). That "(fairly old)" is the key there, as pretty much all modern laptops support DisplayPort over USB-C. I can plug that screen to my 4 year old laptop or my phone using USB-C to USB-C cable and it works, including audio.
You are missing that there is a chip in HDMI side of the cable that converts DisplayPort to HDMI. DisplayPort is what goes over the cable and what the device knows about.
> while what's talked about in the article is widely used

Except it's not, because that functionality is basically nonexistent. All the USB-C to HDMI connectors out there are actually doing the USB-C DisplayPort mode with the equivalent of a DP->HDMI hardware dongle built in.