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Comment on Realized 99% of all my chargers are USB-C. This can only mean one thing. New USB bout to drop!

onslaught545@lemmy.zip ⁨3⁩ ⁨days⁩ ago

I n6ot extremely familiar with the USB-C handshake, but isn’t it between the device and power supply?

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rumba@lemmy.zip ⁨3⁩ ⁨days⁩ ago
It used to be that simple. You could put a certain value of resistor between two pins and that was that.

This guy covered it quite well

superuser.com/…/what-can-a-program-find-out-about…

In brief, Type-C cable specs are nearly independent from USB data and USB Power Delivery (Type-C can support anything).

By specs, Type-C connector/cable provides two methods of self-identification.

First one is by combination of resistor pulls-up and pulls-down on both sides of CC wires. Since there are two CC pins in Type-C connectors, and several analog levels, many combinations are available. Other than connect function itself and basic determination of source-sink roles and power capacity, several “alternate” functions are defined, as Display Port, Audio, and Debug mode.

The second amendment to Type-C is the mandatory embedding of e-markers into every C-C cable. >The information in e-marker contains name of manufacturer and current carrying capability of particular cable.

The state of CC1/CC2 pins is usually acquired by a special CC-controller chip. The CC-controller communicates with main system by I2C interface. The register-based interface is standardized in Intel document USB Type-C Connector System Software Interface Specification

So, many manufacturers are including markers with maximum settings that exceed the wires’/cables’ capability.

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