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0 pointsericswpark2y ago0 comments

Hi, author here. The quote you mentioned from Wikipedia indeed says that devices don't have to implement all the capabilities of the connector. However, further down, it says the following:

> USB-C devices may optionally provide or consume bus power currents of 1.5 A and 3.0 A (at 5 V) in addition to baseline bus power provision; power sources can either advertise increased USB current through the configuration channel, or they can implement the full USB Power Delivery specification using both BMC-coded configuration line and legacy BFSK-coded VBUS line.

And further down:

> However, to connect a USB 2.0/1.1 device to a USB-C host, use of Rd[57] on the CC pins is required, as the source (host) will not supply VBUS until a connection is detected through the CC pins.

See: https://en.wikipedia.org/wiki/USB-C

As the device doesn't implement the full USB PD specs, it must advertise that it wants power through the CC (configuration channel) pins. This is part of the specifications and it must be properly implemented.

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mike_d2y ago

> > However, to connect a USB 2.0/1.1 device to a USB-C host, use of Rd[57] on the CC pins is required, as the source (host) will not supply VBUS until a connection is detected through the CC pins.

Yup. You are referring to the USB 2.0 spec there, not the USB-C spec. If you follow the citation it in turn seems to be citing (not explicitly) the USB-PD spec.

ericswparkOP2y ago

It's a remote that charges via the USB-C port. If it doesn't follow USB 2.0 spec, or the USB-PD spec, or any spec associated with the type-C port, how is it supposed to get power from the host device/charger?

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