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A comment on An Open-Source HDMI Capture Card. Parent comment

Re:An Open-Source HDMI Capture Card by Kirby64 on Monday October 17, 2022 @03:50PM (#33238660)
What scenario would your laptop be providing power (being the source), while simultaneously being the receiver of data (data sink)? Not sure I see the use case for that, regardless of whether you can achieve 5V/3A over PD.
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Re:An Open-Source HDMI Capture Card by seba_dos1 on Monday October 17, 2022 @08:40PM (#33241563)
You need PD for power role swap. You also need PD for alt-mode negotiation. You can get a 5V/3A contract to power a USB-C hub with DisplayPort, for example - that won't work with simply signaling 3A with a resistor.
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Re:An Open-Source HDMI Capture Card by Kirby64 on Tuesday October 18, 2022 @11:08AM (#33248412)
Understood you need PD for alt modes, that's a given. I never thought about the scenario where you have a powered USB hub and you switch from powering it via a brick to powering it via your laptop... interesting, and actually very reasonable scenario. I guess given you have PD already built-in, it's not too hard to integrate that functionality either.
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